MODERATE QUAKE SHAKES GUAM

 

EARTHQUAKE SUMMARY FOR NOVEMBER 23, 2020

 

The strongest earthquake in the world today was an M 5.5 in the region of Guam.

NEIC reported this earthquake of M 5.4 in Guam was felt with intensity II-III in the area(s) of Guam th VI in Sinjana; IV in Tamuning, Barrigada, Hagatna and II-II in Yigo, Dededo, Asan, Yona, and Piti. Two earthquakes of M>=5.4 have occurred in the region near Guam in the past 1.4 years - an M 5.9 on June 23, 2020 and an M 5.4 on May 25, 2020. Today's earthquake was expected in forecast 128874 within about 100 km of this epicenter was likely around November 29. This epicenter is at 103 degrees from the M 7.0 in the Dodecanese Islands of October 30 and was probably promoted by strong concentrated energy from that source. Other earthquakes at this distance from the Dodecanese Islands today included quakes in Flores, Indonesia, Central and southern California, Nicaragua, Oaxaca, Mexico, Chiapas Mexico and Guatemala and in Antofagasta, Chile. These included most of the larger earthquakes in the world (M 4.5-4.9) today.

 

O: 24NOV2020 00:00:22  13.8N  145.7E mb=5.4  EMSC   GUAM REGION                  

P: 29NOV2020 128874    13.0N  145.0E 4.0-5.3 BAAAA  So. Marianas/Guam          

 

The strongest earthquake in the U.S. or Canada today occurred near Sitka, in southeastern Alaska. NEIC reported this earthquake of M 4.3-4.5 in Southeastern Alaska  was felt with intensity II-III in the area(s) of  Southeastern Alaska at Angoon (IV), Sitka, Petersburg, Douglas, Ketchikan, Juneau and in Prince Rupert, British Columbia, Canada. This is the strongest earthquake within about 150 km of this epicenter since and M 5.2 on December 18, 2019. Forecasts 128739 and 129010 had expected today's activity in this region between November 19 and 27.

 

O: 23NOV2020 22:19:55  56.7N  135.9W MB=4.5  ECAN Sitka, AK                      

P: 19NOV2020 128739    58.0N  136.0W 3.0-4.3 BBAAA  Southeast Alaska           

P: 27NOV2020 129010    57.0N  138.0W 3.0-4.3 BABAA  Southeast Alaska           

 

An M 2.7 occurred today in northern New Mexico today. This event is part of the series that has hit the area following September, 2001. This area has been somewhat inactive during 2020 with only five events of M 2.7-2.8 in the past year. An M 3.1 occurred on November 19, 2019, the last quake in the region of larger magnitude. Forecast 128906 had expected today's event was likely within about 20 km of this epicenter around November 25.

 

O: 23NOV2020 13:49:18  36.9N  104.9W ML=2.7  EMSC   NEW MEXICO                    

P: 25NOV2020 128906    36.9N  105.1W 2.0-3.9 AAAAA  Colorado area              

 

 

MODERATE EARTHQUAKES OFF EASTERN JAPAN; NUNAVUT, CANADA WITH GEOMAGNETIC STORM

 

EARTHQUAKE SUMMARY FOR NOVEMBER 22, 2020

 

The strongest earthquake in the world today was an M 5.5 north of Tokyo east of Honshu, Japan. NEIC reported maximum intensity V in Ibaraki, Tochigi and Fukushima; IV in Chiba, Japan. This is the strongest earthquake within about 150 km of this epicenter since an M 5.9 in June 24, 2020. Forecast 128923 had expected today's event was likely within about 50 km of this epicenter around November 25.

 

O: 22NOV2020 10:05:54  36.6N  141.1E Mw=5.5  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 25NOV2020 128923    37.0N  141.0E 4.0-5.4 BAAAA  Off East Coast Honshu      

 

The strongest earthquake in the U.S. or Canada today was an M 4.9-5.3 in northern Canada near Somerset and Prince of Wales, Islands, Nunavut.

Earthquakes Canada reported the mainshock was felt in the epicentral area and was followed by a series of aftershocks. Today's event near the north geomagnetic pole occurred at the height of a strong geomagnetic storm which reached AP 45 at high latitudes early on November 23, the strongest in nearly two months. The only other event of M>=5.3 in the past 30 years in this general region was an M 6.0 on January 8, 2017. At the time this summary noted in this regard:

 

 

"The strongest earthquake in the U.S. or Canada or the world today occurred near the North Geomagnetic Pole (NGP) near Devon Island in northern Canada with M 5.8-6.1. This is a remote area and while this event was reported felt by five people, it was not damaging and no tsunami was reported. There are no previous reports of any earthquake in the area of M>=5.8. Two events of M 5.4-5.7 hit the same general area on December 13, 1987 and March 8, 1963. The unusually large magnitude of this earthquake and the location near the North Geomagnetic Pole suggest some promotional effects from the current geomagnetic storms at high latitudes which have been ongoing for the past week. Today's event may also reflect loss of ice weight as the area responds to regional warming conditions. The loss of ice load can cause rebound in the land beneath." (January 8, 2017)

 

"The geomagnetic field saw major storm conditions today. The AP level was 47.  High latitude geomagnetic field also saw stormy conditions with AP 33. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 29, 2020)

 

Today's event coincided with a geomagnetic storm as noted in this summary:

 

"High latitude geomagnetic field  also saw minor storms conditions with AP 45. This is the most disturbance at high latitudes in the geomagnetic field since September 21, 2020. The last with high latitude greater than 49 occurred October 25, 2019.

 

Forecast 129027 had expected this earthquake was likely in this area around November 27.

 

O: 23NOV2020 04:07:07  73.2N   95.7W ML=2.5  EMSC   SOMERSET ISLAND, NUNAVUT, CANADA

O: 23NOV2020 04:39:25  73.2N   95.7W ML=3.0  EMSC   SOMERSET ISLAND, NUNAVUT, CANADA

O: 23NOV2020 05:54:45  73.2N   95.7W ML=2.7  EMSC   SOMERSET ISLAND, NUNAVUT, CANADA

O: 23NOV2020 03:50:20  73.2N   95.7W MB=5.3  ECAN Resolute, NU. Felt             

O: 23NOV2020 03:50:18  73.2N   96.0W mb=4.9  EMSC   PR. OF WALES ISL., NUNAVUT, CA

O: 23NOV2020 08:38:29  73.2N   95.7W MB=2.0  ECAN Resolute, NU. Aftershock   

O: 23NOV2020 07:05:19  73.2N   95.7W MB=3.5  ECAN Resolute, NU. Aftershock   

O: 23NOV2020 05:54:45  73.2N   95.7W MB=2.7  ECAN Resolute, NU. Aftershock   

O: 23NOV2020 04:52:33  73.2N   95.7W MB=2.3  ECAN Resolute, NU. Aftershock   

O: 23NOV2020 04:39:25  73.2N   95.7W MB=3.0  ECAN Resolute, NU. Aftershock   

O: 23NOV2020 04:07:07  73.1N   95.7W MB=2.5  ECAN Resolute, NU. Aftershock   

P: 27NOV2020 129027    76.0N  106.0W 4.0-5.4 BCBAA  Arctic Ocean Region         

 

An earthquake of M 3.7 in Southeastern Idaho today was followed by an aftershock of M 3.2. NEIC reported these earthquakes of M 2.9-3.2 and M 3.5-3.7 in Southern Idaho were felt with intensity II-III in the area(s) of Southern Idaho in Soda Springs, Grace, Lava Hot Springs, Montpelier and in Jackson, Wyoming.  An earthquake of M>=3.7 last hit within about 200 km of this epicenter on November 15, 2018. Forecast 128993 had expected today's event in this area was likely around November 26.

 

O: 22NOV2020 11:49:15  42.6N  111.4W Ml=3.2  EMSC   SOUTHERN IDAHO

O: 22NOV2020 11:04:15  42.6N  111.5W ML=3.7  EMSC   SOUTHERN IDAHO               

P: 26NOV2020 128993    43.2N  111.0W 2.0-3.8 BAAAA  Yellowstone/Wyoming        

 

STRONG M 6.2 QUAKE SHAKES CENTRAL CHILE

 

EARTHQUAKE SUMMARY FOR NOVEMBER 21, 2020

 

The strongest earthquake in the world today was an M 6.2 in the Maule area of Central Chile. NEIC reported it was felt with intensity IV in Maule at Curico, San Antonio, San Clemente and Linares and in San Antonio, Valparaiso, and San Vicente, O'Higgins. Lesser shaking was observed in Santa Cruz and San Fernando, O'Higgins, San Javier and Cauquenes, Maule. GUC reported this earthquake was felt with intensity   V in  La Araucania at Padre las Casas, Pitrufquen, Renaico and IV in Angol, Curcautin, Perquenco, Temuco, Teodoro Schmidt and Tolten; in Biobio with V in Arauco, Concepcion, Coronel, Hualpen, Lota, Talcahuano, in Nuble with V in Coelemu, Quirihue and San Fabian, in Maule with V in Cauquenes, Colbun, Consitucion, Curico, Maule, encahue, San Clemente, San Javier, Talca, in O'Higgins with V in Chepica, Marchihue, Navidad, Paredones, Pichilemu, Requinoa, San Fernando; in Santiago with IV in Cerro Navia, Colina, El Bosque, El Monte, La Florida, Macul, Penaflor, Puente Alto, San Bernardo and Santiago; in Valparaiso with V in Cartagena, Casablanca, Santo Domingo and Valparaiso; and in Coquimbo with III in Combarbala, Illapel, Los Vilos, Salamanca, Chile. Earthquakes of M>=6.2 have most recently occurred within about 200 km of this epicenter on September 29, 2019 and August 1, 2019 (both M 6.8) and on April 24, 2017 (M 6.9) This quake may have been promoted by high tidal stresses associated with the New Moon as detailed in this report in previous issues:

 

"The new moon arrived on November 15 at 05:07 UT. Longitudes which were antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well." (November 13-18, 2020)

 

Forecasts 128786 and 129056 had expected today's event was likely around November 17-25. This epicenter is at the third node (120 degrees) from the M 7.0 of October 30, 2020 in the Dodecanese Islands and may have been promoted by energy from that source.

 

O: 22NOV2020 00:54     34.6S   73.1W mb=6.1  GUC    La Araucania at Padre las Casa

O: 22NOV2020 00:54:53  34.6S   73.1W mb=6.2  EMSC   OFFSHORE MAULE, CHILE        

P: 17NOV2020 128786    33.0S   73.0W 4.0-5.4 BBAAA  Central Chile              

P: 25NOV2020 129056    34.0S   72.0W 4.0-5.9 BAAAA  Central Chile              

 

An earthquake of M 5.3-5.5 was widely felt in northern Algeria today. It was reported by NEIC with intensity VI in Tamalus and Hamma Bu Ziyan; V in al-Harus, Sakikdah and Constantine, Algeria and IV in Wed-Zenati, Ayn Samaraa, Qalman and Berrrahai and III in Ain Fakroun, Algeria. No major damage was reported with this earthquake. This is the strongest earthquake in northern Algeria within about 150 km of this epicenter since an M 5.5 on May 19, 2013, the only such earthquake in the past 30 years. Other earthquakes in the past 30 years within about 250 km of today's epicenter occurred with M 5.3-5.7 on September 22, 1995; November 10, 2000 and November 18, 2106. Forecasts 128687 and 128912 had expected this activity within about 100 km was likely around November 15-23, 2020.

 

O: 22NOV2020 05:17:53  36.5N    7.1E mb=4.0  EMSC   NORTHERN ALGERIA

O: 22NOV2020 06:32:43  36.5N    7.4E mb=3.9  EMSC   NORTHERN ALGERIA

O: 22NOV2020 03:53:09  36.7N    6.8E mb=5.3  EMSC   NORTHERN ALGERIA              

P: 15NOV2020 128687    37.0N    5.0E 3.0-4.5 CABAA  Western Mediterranean      

P: 23NOV2020 128912    37.0N    6.0E 3.5-4.8 AAAAA  Morocco/Spain              

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in southern Alaska. NEIC reported this earthquake of M 3.6-4.1 in Southern Alaska was felt with intensity II-III in the area(s) of Southern Alaska in Palmer (IV); Eagle River, Chugiak, Valdez, Glennallen and Anchorage. The last earthquake of M>=4.1 within about 150 km of today's event was an M 5.0 and 4.4 on November 7, 2020 and prior to that an M 4.1 on September 13 and an M 4.2 on June 18, 2020.  Forecast 128744 had expected today's event was likely south of this epicenter around November 19.

 

 

O: 21NOV2020 17:20:40  61.7N  148.0W mb=4.1  EMSC   SOUTHERN ALASKA

O: 21NOV2020 15:16:17  61.6N  146.4W ML=3.3  EMSC   SOUTHERN ALASKA              

P: 19NOV2020 128744    60.1N  148.4W 3.2-4.8 BAAAA  Central Alaska             

 

M 5.6 SHAKES CENTRAL CHILE; PROBABLY PROMOTED BY TIDAL STRESS

 

EARTHQUAKE SUMMARY FOR NOVEMBER 20, 2020

 

The strongest earthquake in the world today was an M 5.6 in Coquimbo, Chile. NEIC reported it was felt with intensity V in Coquimbo at Ovalle and IV in La Serena. Intensity II-III was reported from Coquimbo, and Copiapo, Atacama, Chile; Calera, Vina del Mar, Villa Alemana, Valparaiso, Santiago, Mendoza and San Juan, Argentina. GUC reported this earthquake was felt with intensity  VI in  Coquimbo at Combarbala, Punitaqui; V in Vicuna, Rio Hurtado, Paiguano, Ovalle, Coquimbo and Andacollo; IV in Canela, Illapel, Salamanca and III inLos Vilos; in Atacama with V at Alto del Carmen; IV in Freirina, Huasco, Vallenar and II in Caldera, Chanaral, Copiapo, Diego de Almagro, Tierra Amarilla; in Valparaiso with IV in Olmue, Quilpue and Zapallar, Chile. This earthquake occurred near local solar midnight and was probably enhanced by high tidal stresses as reported in previous issues of this summary:

 

"The new moon arrived on November 15 at 05:07 UT. Longitudes which were antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well." (November 13-18, 2020)

 

This is the strongest earthquake in the region of Coquimbo, Chile since an M 5.8 on October 28, 2020 and prior to that an M 6.3 on September 6, 2020. Forecasts 128786 and 128788 had expected today's event within about 100 km of this epicenter was likely in mid-November.

 

O: 21NOV2020 02:11:48  30.9S   71.3W Mw=5.6  EMSC   COQUIMBO, CHILE               

O: 21NOV2020 02:11     30.9S   71.3W mb=5.6  GUC    Coquimbo at Combarbala, Punita

P: 13NOV2020 128786    31.0S   70.0W 4.0-5.3 CAAAA  Central Chile              

P: 14NOV2020 128788    30.0S   71.0W 4.0-5.3 CAAAA  Coast Central Chile        

 

MODERATELY STRONG QUAKE WEST OF MACQUARIE ISLAND

 

EARTHQUAKE SUMMARY FOR NOVEMBER 19, 2020

 

The strongest earthquake in the world, and the only event of M>=5 today was an M 5.7 in the Macquarie Island area south of Australia. This continues a series of moderate to moderately strong earthquakes in this area which began several days ago and included event of M 4.6 on November 9; an M 5.7 on November 13 and and M 4.4 on November 14. These events occurred about 1000 km to the east of today's activity. The last activity within about 300 km of today's event with M>4 occurred on August 27, 2020 with M 4.8. The last earthquake of M>=5.7 within about 500 km of today's epicenter was an M 6.0 on August 21, 2019 and an M 6.5 April 18, 2019 and M 5.9 February 27, 2016.

 

O: 20NOV2020 03:19:15  53.9S  140.4E Mw=5.7  EMSC   WEST OF MACQUARIE ISLAND     

 

Elevated seismicity also continued in Sumatra, Indonesia today where an event of M 4.7-4.8 was the second strongest recorded in the world in the past 24 hours. Forecast 128768 had expected today's event south of Sumatra was likely in mid-November.

 

O: 19NOV2020 18:10:57   1.5S   99.7E mb=4.7  EMSC   KEP. MENTAWAI REGION, INDONESI

O: 19NOV2020 23:12:39   3.4S  101.7E ML=3.9  EMSC   SOUTHERN SUMATRA, INDONESIA  

P: 12NOV2020 128768     5.0S  103.0E 4.0-5.3 CBBAA  So. of Java                

 

A moderate M 4.5 was also felt widely today in western Mindanao, Philippines.

NEIC reported this earthquake of M 4.5 in Western Mindanao, Philippines was felt with intensity II-III in the area(s) of Western Mindanao, Philippines at Tawagan (VI); Aurora, Dipolog, Tambulig (IV);  Oroquieta, Ozamiz, Kapipunan, Kapatagan, Sindangan, Dicoyong.  PHIVOLCS reported this earthquake was felt with intensity IV in Pagadian City; III in Dapitan City; Dipolog City, Oroquieta City and Sapang Dalaga, Misamis Occidental; Alicia, Imelda and Buug, Zamboanga Sibugayp Dinas and Molave, Zamboanta del Sur; II in Tudela, Aluran & Ozamis, misamis Occidental; Liloy, Zamboanga del Norte and I in Dumaguete City and Zamboanga City. The last shallow focus earthquake within about 150 km of this epicenter in

Western Mindanao was and M 4.5 on July 30, 2020. This preceded an M 6.4 at a  deep hypocenter (479 km) on August 1, 2020 and may have been precursory to that event. Forecast 128564 had expected today's activity in mid-November.

 

O: 19NOV2020 12:14:09   7.9N  123.3E mb=4.5  EMSC   MINDANAO, PHILIPPINES        

P: 17NOV2020 128564     6.0N  124.0E 4.0-5.3 ABAAA  Mindanao, Philippines      

 

The strongest earthquake in the U.S. or Canada today was an M 3.6 south of Alaska. This is typical daily aftershock activity following the M 7.6 in the Alaska Peninsula of October 19. Forecast 128725 had expected today's activity within 50 km of this epicenter was likely around November 20.

 

O: 19NOV2020 12:45:28  54.6N  159.7W ml=3.6  EMSC   SOUTH OF ALASKA              

P: 20NOV2020 128725    54.9N  159.9W 3.5-4.8 AAAAA  Alaska Peninsula           

 

A swarm of light earthquakes up to M 4.1 occurred near the coast of Nicaragua today. These were not reported felt. They occurred in an area which Hurricane Iota passed over the past two days. It is likely they were promoted by stresses from that storm as noted in previous issues of this report:

 

"Hurricane Iota continued east of Nicaragua today with winds up to 135 kts. It is expected to track to the west reaching Nicaragua around November 16-17. Regional seismicity is expected to be high while this storm is in the area, especially in conjunction with the new moon." (November 16, 2020)

 

High tidal stresses associated with the new moon may also have helped promote this activity in Nicaragua today which followed several light to moderate events in the area in the past several days. The tidal forecast for seismicity with this new moon had noted:

 

"The new moon arrived on November 15 at 05:07 UT. Longitudes which were antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well." (November 13-18, 2020)

 

Forecast 128592 had expected today's activity was likely within about 100 km around November 17. This activity is at 101-103 degrees from the M 7.0 in the Dodecanese Islands of October 30 and was probably also promoted by concentrated energy from that source. Other seismicity at this distance from Greece occurred with moderate magnitudes in Oaxaca, Chiapas, the Gulf of California, Mexico; an M 3.7 in Baja California; Ecuador, Central California, Southern California, the Banda Sea and northern Chile.

 

O: 19NOV2020 09:20:10  11.2N   86.9W ML=3.6  EMSC   NEAR COAST OF NICARAGUA

O: 19NOV2020 09:25:51  11.2N   86.9W ML=3.5  EMSC   NEAR COAST OF NICARAGUA

O: 19NOV2020 20:25:17  12.0N   87.8W ML=4.1  EMSC   NEAR COAST OF NICARAGUA

O: 19NOV2020 16:35:52  12.6N   88.0W ML=3.5  EMSC   NEAR COAST OF NICARAGUA      

P: 17NOV2020 128592    13.0N   89.0W 3.5-5.1 AAAAA  Coast of Central America   

 

MODERATE SEISMICITY CONTINUES IN WESTERN INDONESIA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 18, 2020

 

It was a very quiet day in global seismicity today. No earthquakes of M>=5 were recorded on this day. The highest seismicity occurred in western Indonesia and the Mariana Islands with quakes of M 4.9, 4.8 and 4.7. The activity in Sumatra continued regional activation which has included an M 6.3 and 5.3 in the region in the past two days. Today's event in southern Sumatra had been anticipated in forecast 128768 within about 25 km in mid-November.

 

O: 18NOV2020 11:37:55   4.7S  102.9E mb=4.7  EMSC   SOUTHERN SUMATRA, INDONESIA  

P: 12NOV2020 128768     5.0S  103.0E 4.0-5.3 CAAAA  So. of Java                

 

The earthquake in the northern Mariana Islands was expected within about 50 km was possible around November 19 in forecast 128606. The last such earthquake  within about 100 km of this epicenter with M>=4.9 occurred a month ago on October 20, 2020.

 

O: 18NOV2020 19:05:12  17.6N  145.9E mb=4.9  EMSC   ALAMAGAN REG, N. MARIANA ISLAN

P: 19NOV2020 128606    18.0N  146.0E 4.0-5.4 AAAAA  No. Marianas               

 

O: 18NOV2020 08:41:19   9.4S  118.5E ML=4.8  EMSC   SUMBAWA REGION, INDONESIA    

P: 17NOV2020 128571     8.0S  121.0E 4.0-5.3 ABBAA  Flores Island area         

 

An M 4.3-4.5 occurred today in the Virgin Islands. NEIC reported it was felt with intensity II-III in the Virgin Islands at Saint Thomas and Saint John and in Puerto Rico with IV in San Juan and II-III in Culebra, Puerto Real, Vieques, Carolina. The only other event of M>=4.3 within about 100 km of this epicenter in the past year was an M 4.4 on December 28, 2019. The last such event of M>=4.5 occurred as an M 4.9 on November 14, 2018. Forecast 128498 had expected today's event was likely around November 18 within about 25 km of the epicenter.

 

NEIC reported the earthquake of M 3.6 in Puerto Rico  was felt with intensity II-III in the area(s) of  Puerto Rico with IV at Rincon, Mayaguez and II-III in Aguada, Anasco and Isabela.

 

O: 18NOV2020 12:20:40  18.8N   65.3W MD=3.3  EMSC   PUERTO RICO REGION           

O: 18NOV2020 12:20:40  18.8N   65.3W MD=3.6  ANSS   PUERTO RICO REGION           

O: 19NOV2020 02:51:20  18.8N   65.3W Md=3.1  EMSC   PUERTO RICO REGION

O: 18NOV2020 11:59:09  18.9N   65.1W Mw=4.3  EMSC   VIRGIN ISLANDS REGION

O: 18NOV2020 11:59:09  18.9N   65.1W Mw=4.5  EMSC   VIRGIN ISLANDS REGION

P: 18NOV2020 128598    19.0N   65.0W 3.0-4.9 AAAAA  Leeward Islands            

 

The largest earthquake in the U.S. or Canada today was an M 3.9-4.0 in the region of the Queen Charlotte Islands. It was not reported felt in this area. The last earthquake of larger magnitude in this area was an M 4.6 about 200 km southeast of this epicenter on February 14, 2020 and prior to that an M 4.0 about 50 km south of today's epicenter. A similar event also occurred on November 9, 2019. Forecast 128730 had expected today's event within about 50 km of today's epicenter.

 

O: 18NOV2020 22:19:49  53.2N  132.3W MB=4.0  ECAN of Vancouver, BC    

O: 18NOV2020 22:19:45  53.0N  132.8W mb=3.9  EMSC   QUEEN CHARLOTTE ISLANDS REGION

P: 16NOV2020 128730    53.0N  133.0W 3.0-4.9 AAAAA  British Colombia           

 

MODERATE SEISMICITY CONTINUES NEAR SUMATRA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 17, 2020

 

The strongest earthquake in the world today, on a quiet day in global seismicity, occurred as an M 5.3 in southern Sumatra.  NEIC reported this earthquake of M 5.2-5.3 in Southern Sumatra, Indonesia  was felt with intensity II-III in the area(s) of  Southern Sumatra, Indonesia and in Malaysia. It follows and M 6.3 in the area to the west yesterday. This earthquake occurred within minutes of local solar noon and was probably promoted by high tidal stresses as noted in previous issues of this summary:

 

"The new moon arrived on November 15 at 05:07 UT. Longitudes which were antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well.

 

A similar series of earthquakes occurred south of today's epicenter on October 17 and 19 with M 5.3, 5.6 and 5.5 with the previous new moon. The only other such event in the area of M>=5.3 in the past year was an M 5.6 on December 16, 2019. At the time of the October activity this summary noted in this regard:

 

"The M 5.3 south of Sumatra continued a swarm in the area which began with an M 5.4 on October 15, 2020. It is the second largest event in this swarm to date.

It occurred near local solar midnight and may have affected by high tidal stresses with the new moon." (October 18, 2020)

 

Forecast 128768 had expected activity in this area in mid-November.

 

O: 18NOV2020 04:42:01   1.8S  100.5E Mw=5.3  EMSC   SOUTHERN SUMATRA, INDONESIA  

P: 12NOV2020 128768     5.0S  103.0E 4.0-5.3 CCCAA  So. of Java                

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the Northwest Territories of Canada. It was not reported felt in this remote area. The earthquake occurred within minutes of local solar noon and it was probably promoted by high tidal stresses which maximize at this hour. This is the strongest earthquake within about 200 km of this epicenter since events of M 4.5 and 4.6 about 200 km southwest of this on July 15, 2014 and prior to that an M 4.4-4.7 about 200 km to the northwest on March 2, 2012. An earthquake of M 5.3 on September 26, 2011 within about 25 km of this epicenter occurred. Today's event may have been a long-period aftershock of that event. Forecast 128750 had expected today's activity was likely around November 19.

 

O: 17NOV2020 20:50:55  63.6N  126.3W mb=4.4  EMSC   NORTHWEST TERRITORIES, CANADA

P: 19NOV2020 128750    62.1N  124.2W 2.5-3.8 ABAAA  Northwest Terr., Canada    

 

Two earthquakes of M 3.5 occurred in the region of Southern California east of Los Angeles today.  NEIC reported the earthquake of M 3.5 in Southern California  was felt with intensity II-III in the area(s) of  Southern California at Hesperia and Ontario.  NEIC reported the earthquake of M 3.5 in Southern California  was felt with intensity II-III in the area(s) of  Southern California at Forest Falls, Morongo Valley, White Water, Banning, Cabazon, Desert Hot Springs, Yucca Valley, Palm Springs, Big Bear Lake and Yucaipa.

This area has been relatively quiet in recent months. An M 3.7 occurred with the last new moon on October 19 near the second epicenter near Morongo Valley. An M 3.7 on September 15, 2020 occurred within about 75 km of the first of these events. Forecast 128671 had expected this activity was likely around November 15.

 

O: 17NOV2020 07:19:20  34.1N  116.7W ML=3.5  EMSC   SOUTHERN CALIFORNIA          

O: 17NOV2020 17:32:32  34.9N  116.3W Mw=3.5  EMSC   SOUTHERN CALIFORNIA          

P: 15NOV2020 128671    34.4N  116.7W 2.5-4.3 AAAAA  So. California              

 

 

M 6.3 SOUTH OF SUMATRA RELATED TO NEW MOON TIDAL STRESSES

 

EARTHQUAKE SUMMARY FOR NOVEMBER 16, 2020

 

The strongest earthquake in the world today was an M 6.3 south of Sumatra, Indonesia.  BMG reported it was felt with intensity III-IV in Padang, Painan and Sipora; II-III in Padang Panjang, Bukittinggi, Pariaman, Kepahiang and I-III in Pasaman, Kerinci, Payakumbuh and Solok, Selatan, Indonesia. This event may have been promoted by strong tidal stresses associated with today's new moon as noted in previous issues of this summary:

 

"The new moon arrived on November 15 at 05:07 UT. Longitudes which were antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well.

 

This summary had also noted the seismic potential of this area when Tropical Cyclone Alicia formed near this epicenter. That analysis on November 15 had noted in this regard:

 

"TC Alicia formed in conjunction with an M 4.5 in the South Indian Ocean on November 10 and both may have been initiated by similar set of conditions in the area. This set of phenomena has previously been noted in this summary in this area and  in areas to the northeast in Indonesia and the Philippines." (November 15, 2020) 

 

and

 

"A Tropical cyclone may be forming south of Sumatra. This system is currently located at 4S 89E and moving WSW with winds up to 30 kts. An unusual earthquake occurred under the eye of this storm with M 4.7 yesterday and may have been triggered by atmospheric unloading from this storm." (November 10, 2020)

 

O:  9NOV2020 09:30:42  4.4S  91.9E mb=4.5  EMSC   SOUTH INDIAN OCEAN" (November 15, 2020)

 

The last earthquake of M>=6.3 within about 200 km of this epicenter in Indonesia was an M 6.3 was an M 6.3 about 200 km to the north on August 31, 2017. The last such event within about 150 km was an M 7.0 on February 25, 2008. Forecasts 128768 had expected today's event was likely in mid-November. This activity is at 99-100 degrees from the M 7.6 in the Gulf of Alaska of October 19 and may have been promoted by concentrated energy from that source.

 

O: 17NOV2020 01:44:09   2.7S   99.2E Mw=5.8  EMSC   MENTAWAI REGION, INDONESIA   

O: 17NOV2020 01:44:09   2.9S   99.1E Mw=6.3  BMG    MENTAWAI REGION, INDONESIA   

P: 12NOV2020 128768     5.0S  103.0E 4.0-5.3 BCCAA  So. of Java                

 

A moderate earthquake also occurred near the antipode of the Sumatra epicenter today. Epicenters which are antipodal can be related to each other but in the current case, these were both probably triggered by high tidal stresses. Forecast 128313 had expected today's event in Colombia was likely around November 11 within about 150 of today's epicenter.

 

NEIC reported this earthquake of M 4.8 in Colombia  was felt with intensity II-III in the area(s) of  Colombia at Cali Valle del Cauca.

 

O: 16NOV2020 13:59:20   4.8N   76.4W mb=4.8  EMSC   COLOMBIA                     

P: 11NOV2020 128313     5.0N   78.0W 4.0-5.3 BABAA  Colombia                   

 

 

An unusual earthquake of M 3.5 was widely felt in the Western Cape Province of South Africa today. NEIC reported it was felt with intensity IV in the Western Cape at Saldanha, Atlantic, and Bredasdorp and II-III in Mooreesburg, Malmesbury, Cape Town, Paarl, Steeenbosch, Somerset and Carnarvon. The last earthquake in the Cape area of South Africa with M>=3.5 within about 500 km of this epicenter occurred on December 31, 1994  with M 4.5 about 500 km northeast of today's epicenter, the only such regional event in the past 30 years. This epicenter is at the fifth node (72 degrees) from the Dodecanese Islands of October 30 (M 7.0).

 

O: 16NOV2020 22:27:04  33.4S   17.9E mb=3.5  EMSC   SOUTH AFRICA                 

 

 

The strongest earthquake in the U.S. or Canada today was an M 4.2-4.4 in the area of Yakutat, Southeastern Alaska. NEIC reported this earthquake of M 4.2 in Southeastern Alaska was felt with intensity II-III in the area(s) of Southeastern Alaska at Yakutat. An M 3.8 aftershock followed the mainshock. The last earthquake within about 150 km of this epicenter with M>=4.4 were of M 6.2 and 6.3  on May 1, 2017. Forecast 128739 had expected today's earthquake in this area was likely around November 14.

 

O: 16NOV2020 17:18:17  59.8N  138.9W mb=4.2  EMSC   SOUTHEASTERN ALASKA          

O: 16NOV2020 18:51:59  59.7N  138.9W MB=3.8  ECAN Yakutat, AK                     

O: 16NOV2020 17:18:16  59.7N  138.9W MB=4.4  ECAN Yakutat, AK                    

P: 14NOV2020 128739    59.0N  138.0W 3.0-4.3 AAAAA  Southeast Alaska           

 

The enhanced aftershock activity in Southern Idaho today included an M 3.8.

NEIC reported this earthquake of M 3.8 in Southern Idaho was felt with intensity II-III in the area(s) of Southern Idaho at Meridian and Caldwell.  This follows events of M 4.7 and 4.4 in the area over the past two days. Forecast 128703 had expected today's activity was likely around November 16.

 

O: 16NOV2020 08:21:05  44.3N  115.0W ML=2.5  EMSC   SOUTHERN IDAHO

O: 16NOV2020 09:31:19  44.3N  115.0W Ml=2.1  EMSC   SOUTHERN IDAHO

O: 16NOV2020 11:17:12  44.3N  115.2W Ml=2.2  EMSC   SOUTHERN IDAHO

O: 16NOV2020 18:59:39  44.3N  115.0W ML=2.7  EMSC   SOUTHERN IDAHO

O: 17NOV2020 02:20:03  44.3N  115.0W Ml=3.8  EMSC   SOUTHERN IDAHO

O: 17NOV2020 02:11:48  44.4N  115.3W ML=2.6  EMSC   SOUTHERN IDAHO

O: 16NOV2020 18:52:51  44.5N  115.2W Ml=2.6  EMSC   SOUTHERN IDAHO

O: 16NOV2020 23:05:04  44.5N  115.2W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 16NOV2020 17:02:23  44.2N  115.1W ML=2.7  EMSC   SOUTHERN IDAHO               

P: 16NOV2020 128703    44.5N  115.2W 2.0-3.8 AAAAA  Montana/Idaho              

 

 

 

 

 

 

STRONG QUAKE SHAKES PHILIPPINES

 

EARTHQUAKE SUMMARY FOR NOVEMBER 15, 2020

 

The strongest earthquake in the world today was an M 6.1 in the region of Mindanao, Philippines. NEIC reported maximum intensity VI in Caraga at Marihatag, V in Posario and IV in Lagnglong and Alegria. Intensity II-III was reported from Basag, Butuan, Kinamayan, Cancolan, Barra and Pandan, Mindanao, Philippines. PHIVOLCS reported intensity VI in Hunatuan, Surigao del Sur; V in San Agustin, City of Bislig, Lianga and Lingig, Surigao del Sur, Bayugan City, Rosario, Talacogon, San Francisco and Santa Josefa, Agusan del Sur; IV in Bayabas, Borobo, Cagwait, Lanuza, Marihatag and Tago, Surigao del sur; Laak, Mabini, Maco Maragusan, Mawab, Monkayo, Nabunturan and Pantukan, Davao de Oror; Butuan City. Intensity I was felt from Iligan City Southern Leyte, Camiguin Island, Davao Oriental, Surgao del Norte and southern Mindanao. This event may have been promoted by strong tidal stresses associated with today's new moon as noted in previous issues of this summary:

 

"The new moon arrived on November 15 at 05:07 UT. Longitudes which were antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well.

 

It is also likely that today's event in the central Philippines was promoted by stresses from Typhoon Vamco which passed through this area several days ago as noted in this summary at the time:

 

"Typhoon Vamco continued east of the Central Philippines today with winds up to 90 kts. It is expected to track to the west with moderate effects on regional seismicity as it passes through the Central Philippines." (November 11, 2020)

 

This is the strongest earthquake in the northern Mindanao area of the Philippines within about 200 km of this epicenter since an M 6.1 on November 2, 2012.  Forecast 128554 had expected today's event was likely within about 50 km around November 15.

 

O: 15NOV2020 22:37:43   8.7N  126.3E Mw=6.1  EMSC   MINDANAO, PHILIPPINES        

P: 15NOV2020 128554     9.0N  126.0E 4.0-5.3 AAAAA  Central Philippines        

 

The strongest earthquake in the U.S. or Canada outside Alaska. today was an M 4.1 in the area of southern Idaho. NEIC reported it was felt with maximum intensity IV in Stanley and II-III in Idaho at Lowman, Clayton, Ketchum, Challis, Horseshoe Bend, Hailey, May, Garden City and Boise. NEIC reported this earthquake of M 4.1 in Southern Idaho was felt with intensity II-III in the area(s) of Southern Idaho at Stanley and Lowman. This continues the swarm in Idaho which began slightly more than an hour after the M 5.4 near Mina, Nevada on November 13. Previous issues of this summary have been following this swarm as:

 

"Moderate earthquakes continued today in the southern Idaho aftershock zone. This included an M 4.7, the strongest aftershock to date of the M 6.5 area of March 31, 2020. NEIC reported the strongest of these of M 4.3, 3.7 and 3.8 were felt with intensity IV in Fairfield and II-III in Idaho at Stanley, Cascade, Eagle, Lowman, Garden Valley, Boise. The only other events in this general region of southern Idaho with M>=4.7 in the past 30 years occurred as the mainshock on March 31, 2020 and as an M 4.7 on January 28, 1995. In the previous issue of this report it was noted in regard to the Idaho swarm:

 

"The swarm in southern Idaho today included events of M 3.0, 3.0 and 2.9 as well as a series of smaller events. This continues the strong aftershock sequence of the M 6.5 in the area of March 30, 2020. Forecast 128703 expected today's activity was likely around November 12." (November 13, 2020)

 

Several foreshocks to the M 4.7 occurred within minutes of local solar midnight and were probably promoted by high tidal stresses associated with the upcoming new moon. This activity is located at the fourth node (90 degrees) from the M 7.0 in the Dodecanese Islands of Greece and Turkey of October 30 and was probably promoted by energy from that source. The mainshock occurred about an hour and a half after the M 5.4 in western Nevada today and was also probably triggered by strong energy from that source." (November 13, 2020)

 

The M 4.1 today began near local solar noon and may have been promoted by strong tidal stresses associated with the new moon.

 

O: 15NOV2020 20:12:29  44.3N  115.0W ML=2.6  EMSC   SOUTHERN IDAHO

O: 15NOV2020 20:48:23  44.3N  115.0W Mw=4.1  EMSC   SOUTHERN IDAHO

O: 15NOV2020 21:36:42  44.3N  115.0W ML=3.1  EMSC   SOUTHERN IDAHO

O: 15NOV2020 22:22:44  44.3N  115.0W ML=3.5  EMSC   SOUTHERN IDAHO

O: 15NOV2020 22:37:14  44.3N  115.0W ML=3.3  EMSC   SOUTHERN IDAHO

O: 15NOV2020 23:17:24  44.3N  115.1W ML=3.6  EMSC   SOUTHERN IDAHO

O: 15NOV2020 23:21:11  44.3N  115.0W ML=2.6  EMSC   SOUTHERN IDAHO

O: 16NOV2020 02:23:29  44.3N  115.0W ML=2.6  EMSC   SOUTHERN IDAHO

O: 16NOV2020 05:01:30  44.3N  115.0W ML=2.6  EMSC   SOUTHERN IDAHO

O: 15NOV2020 21:07:20  44.4N  115.0W ML=2.9  EMSC   SOUTHERN IDAHO

O: 16NOV2020 03:53:20  44.4N  115.0W ML=2.5  EMSC   SOUTHERN IDAHO

P: 12NOV2020 128703    44.5N  115.2W 2.0-3.8 AAAAA  Montana/Idaho              

 

 

An M 4.7 also occurred in the Alaska Peninsula aftershock zone. The mainshock hit with M 7.6 on October 19 and has seen a very energetic aftershock sequence. The last aftershock of M>=4.7 in this area was an M 5.1 on November 5, 2020. Today's event is the second strongest aftershock since the M 7.6 on October 19 and the immediate aftershocks of October 19-21. Forecast 128725 had expected today's event was likely around November 14.

 

 

O: 15NOV2020 17:51:04  54.3N  159.7W ML=3.6  EMSC   SOUTH OF ALASKA

O: 15NOV2020 21:14:21  54.6N  159.7W mb=4.7  EMSC   SOUTH OF ALASKA               

P: 14NOV2020 128725    54.7N  158.9W 3.5-4.8 AAAAA  Alaska Peninsula           

 

Aftershocks of the M 5.4 event near Mina, Nevada of November 14 continued today but remained at subdued levels. The strongest event today was M 3.3. This summary speculated on this sudden decline in aftershock activity in the previous issue of this summary as:

 

"Aftershocks in western Nevada were not significant today. The only event of

M>=3 was an M 3.3. These follow the M 5.4 on November 13, 2020. The quiet in the aftershock zone may indicate that most of the motion and stress available at this time was taken by the mainshock and by the M 6.5 on May 15.  Forecast 128638 had expected moderate aftershocks at this time." (November 15, 2020)

 

O: 16NOV2020 04:43:07  38.2N  117.8W ML=3.3  EMSC   NEVADA

P: 16NOV2020 128638    38.4N  117.8W 2.5-4.5 AAAAA  California/Nevada area     

 

The strongest earthquake in the Western Hemisphere today was an M 5.3 in Salta, Argentina. This is the largest earthquake within about 200 km of this epicenter since an M 5.4 on April 30, 2020.  Forecast 128775 had expected this activity was likely around November 19. It was probably promoted by high tidal stresses associated with the new moon (see tidal forecast in this issue).

 

O: 15NOV2020 12:18:06  23.4S   66.8W mb=4.5  EMSC   JUJUY, ARGENTINA             

O: 15NOV2020 12:33:13  24.2S   67.5W Mw=5.3  EMSC   SALTA, ARGENTINA             

P: 19NOV2020 128775    23.0S   69.0W 4.0-5.4 BBBAA  Coast No. Chile            

 

A swarm of moderate earthquakes in the Northern Mid-Atlantic of M 4.8, 4.9 and 4.9 today may have been promoted by high tidal stresses as well as regional stresses from Tropical Storm Theta. TS Theta passed near this epicenter several days ago and was noted in this summary at the time as:

 

"TS Theta continued  in the north Atlantic Ocean with winds up to 60 kts. It is expected to track to the north and east reaching the coast of Spain later in the week. Seismicity in Spain, France and Portugal is expected to be enhanced as this storm makes landfall." (November 9, 2020)

 

O: 15NOV2020 11:15:02  17.7N   46.6W mb=4.9  EMSC   NORTHERN MID-ATLANTIC RIDGE

O: 15NOV2020 11:37:24  17.7N   46.5W mb=4.9  EMSC   NORTHERN MID-ATLANTIC RIDGE

O: 15NOV2020 11:31:31  17.5N   46.5W mb=4.8  EMSC   NORTHERN MID-ATLANTIC RIDGE  

P: 19NOV2020 128604    15.0N   46.0W 4.0-5.3 BCAAA  Mid-Atlantic Ridge         

 

MODERATE MID-INDIAN RIDGE QUAKE ASSOCIATED WITH TROPICAL CYCLONE ALICIA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 14, 2020

 

The strongest earthquake in the world today was an M 5.2 in the mid-Indian Ridge. The last earthquake within about 250 km of this epicenter with M>=5.2 was an M 5.4 in September, 2018. The largest earthquakes in this area in the past 20 years were of M 5.7 on March 26, 2009 and M 5.6 on January 1, 2002. Today's earthquake may have been promoted by energy from Tropical Cyclone Alicia which formed two days ago south of India and as noted in previous issues of this summary was expected to affect seismicity along the mid-Indian Ridge as:

 

"Tropical cyclone Alicia continued south of India today with winds up to 75 kts. This system is expected to track to the south and west over the next several days. Some enhanced seismicity in the area of the South Indian Ocean may occur as this system moves through the area." November 13-14, 2020)

 

and

 

"A Tropical cyclone may be forming south of Sumatra. This system is currently located at 4S 89E and moving WSW with winds up to 30 kts. An unusual earthquake occurred under the eye of this storm with M 4.7 yesterday and may have been triggered by atmospheric unloading from this storm." (November 10, 2020)

 

The earthquake in the South Indian Ocean occurred on November 9 with the following parameters: It was first recorded within about 300 km of this epicenter since an M 4.7 on April 24, 2020.

 

O:  9NOV2020 09:30:42  4.4S  91.9E mb=4.5  EMSC   SOUTH INDIAN OCEAN            

 

 

TC Alicia formed in conjunction with an M 4.5 in the South Indian Ocean on November 10 and  both may have been initiated by similar set of conditions in the area. This set of phenomena has previously been noted in this summary in this area and  in areas to the northeast in Indonesia and the Philippines. 

 

The predecessor to this event on April 24, 2020 had been noted in this summary because of its unusual location as:

 

"An M 4.7 also occurred south of India today within about a minute of local solar noon and was probably promoted by tidal stresses (the new moon arrived on April 23, 2020). This event is  the strongest within about 300 km of this epicenter since an M 5.5 on March 10, 2019 and prior to that an M 5.5 on May 13, 2012." (April 24, 2020)

 

O: 14NOV2020 10:39:15  27.8S   74.1E mb=5.2  EMSC   MID-INDIAN RIDGE             

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the Near Islands, Aleutians. It was not reported felt in this remote area. The last earthquakes of greater magnitude in the Near Islands occurred with M 4.9 on February 12 and M 5.1 on January 1, 2020. The only other event in the region with M>=4.4 this year was an M 4.4 on November 8, 2020. Forecast 128733 had expected today's event in the Near Islands was likely around November 16.

 

 

O: 15NOV2020 05:34:05  52.6N  171.6E mb=4.4  EMSC   NEAR ISLANDS, ALEUTIAN ISLANDS

P: 16NOV2020 128733    54.0N  170.0E 4.0-5.5 ABAAA  Near Islands               

 

Aftershocks in western Nevada were not significant today. The only event of M>=3 was an M 3.3. These follow the M 5.4 on November 13, 2020. The quiet in the aftershock zone may indicate that most of the motion and stress available at this time was taken by the mainshock and by the M 6.5 on May 15. Forecast 128638 had expected moderate aftershocks at this time.

 

O: 14NOV2020 12:42:36  38.2N  117.9W ML=3.3  EMSC   NEVADA

P: 13NOV2020 128638    38.2N  117.7W 2.5-5.5 AAAAA  California/Nevada area     

 

The strongest earthquakes in the region of California today occurred in the swarm in Baja California with M 3.6 and 3.7. This swarm began in late October. The largest earthquake in the swarm to date have been several of M 3.6-3.7 so today's events of M 3.6 and 3.7 are significant inclusions. This activity is at 103 degrees from the M 7.0 in the Dodecanese Islands of October 30 and may have been promoted by energy from that source. Forecast 128669 had expected this activity was likely around November 14.

 

O: 14NOV2020 10:55:51  31.5N  115.6W ML=3.6  EMSC   BAJA CALIFORNIA, MEXICO      

O: 14NOV2020 10:50:15  31.5N  115.6W ML=3.7  EMSC   BAJA CALIFORNIA, MEXICO      

P: 14NOV2020 128669    31.9N  116.3W 2.5-4.8 AAAAA  So. California             

 

 

MODERATE QUAKE SHAKES PAKISTAN

 

EARTHQUAKE SUMMARY FOR NOVEMBER 13, 2020

 

An earthquake of M 5.5 was widely felt in Pakistan today. NEIC reported maximum intensity VI in Ziarat and Quetta, Baluchistan and in Karachi, Sind, Pakistan and V in Kot Abdul Malik, Punjab, Pakistan. The last earthquake within about 300 km of this epicenter with M>=5.5 was an M 5.5 on May 13, 2016. Strong earthquakes of M 6.4 and 6.4 hit this region within about 50 km of today's epicenter on October 28 and 29, 2008. Today's event may be a long-period aftershock of those.  This summary reported on that activity in 2008 as follows:

 

"A strong earthquake of M 6.4 occurred in Balochistan northeast of Quetta, Pakistan. This earthquake resulted in damage and casualties. According to

ASC at least 14 were killed and more than 40 were injured and many buildings collapsed in the Kanozai tehsil near Pishin. Several people were injured in the Pishin and Quetta areas as mud brick buildings collapsed or as people ran from their homes in panic. Power supplies were disrupted in the area. Tremor was strongly felt at Quetta as well as part of northern and central Balochistan including Loralai. Damage to mud-walled buildings were reported from Chaman,

Killa Abdullah, Pishing, Ziarat and from Quetta including at Nawakilli and

Pashtunabad on the outskirts of the city. Many people spent the rest of the morning outdoors in fear of further tremors. The Mw 6.4 was preceded by a Mb 5.2 foreshock. NEIC reported the quake was felt with intensity IV at Quetta, Pakistan and with intensity III at Qandahar, Afghanistan. The earthquake hit near the epicenter of one of the largest earthquakes in the past century - an M 8.5-9.5 which hit in 1935 killing more than 30,000 people." (October 29, 2008)

 

Forecasts 128375 and 128409 had expected today's activity was likely in Pakistan around November 7-11.

 

O: 14NOV2020 02:56:54  30.4N   67.6E Mw=5.5  EMSC   PAKISTAN                     

P:  7NOV2020 128375    29.0N   58.0E 3.5-4.8 CBCAA  So. Iran/Persian Gulf      

P: 11NOV2020 128409    34.0N   70.0E 3.8-5.1 BCBAA  Pakistan                   

 

The strongest earthquake in the world today was an M 5.7 in the Macquarie Island region south of New Zealand. It was not reported felt in this remote area. The last earthquake within about 300 km of this epicenter with M>=5.7 in the Macquarie Islands area occurred March 1, 2019 with M 5.8 and prior to that on September 8, 2016. This epicenter is at 144 degrees from the Dodecanese Islands M 7.0 of October 30 and was probably promoted by energy from that source.

 

O: 13NOV2020 09:12:46  53.0S  159.9E Mw=5.7  EMSC   MACQUARIE ISLAND REGION      

 

Moderate earthquakes continued today in the southern Idaho aftershock zone. This included an M 4.7, the strongest aftershock to date of the M 6.5 area of March 31, 2020. NEIC reported the strongest of these of M 4.3, 3.7 and 3.8 were felt with intensity IV in Fairfield and II-III in Idaho at Stanley, Cascade, Eagle, Lowman, Garden Valley, Boise. The only other events in this general region of southern Idaho with M>=4.7 in the past 30 years occurred as the mainshock on March 31, 2020 and as an M 4.7 on January 28, 1995. In the previous issue of this report it was noted in regard to the Idaho swarm:

 

"The swarm in southern Idaho today included events of M 3.0, 3.0 and 2.9 as well as a series of smaller events. This continues the strong aftershock sequence of the M 6.5 in the area of March 30, 2020. Forecast 128703 expected today's activity was likely around November 12." (November 13, 2020)

Several foreshocks to the M 4.7 occurred within minutes of local solar midnight and were probably promoted by high tidal stresses associated with the upcoming new moon. This activity is located at the fourth node (90 degrees) from the M 7.0 in the Dodecanese Islands of Greece and Turkey of October 30 and was probably promoted by energy from that source. The mainshock occurred about an hour and a half after the M 5.4 in western Nevada today and was also probably triggered by strong energy from that source.

 

O: 14NOV2020 04:28:46  44.3N  115.2W ML=3.6  EMSC   SOUTHERN IDAHO

O: 13NOV2020 10:52:59  44.4N  115.2W Ml=2.7  EMSC   SOUTHERN IDAHO

O: 13NOV2020 10:54:33  44.4N  115.2W Ml=4.7  EMSC   SOUTHERN IDAHO

O: 13NOV2020 11:14:34  44.4N  115.2W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 13NOV2020 11:30:43  44.4N  115.2W Ml=2.6  EMSC   SOUTHERN IDAHO

O: 13NOV2020 11:55:01  44.4N  115.2W Ml=2.7  EMSC   SOUTHERN IDAHO

O: 13NOV2020 15:07:43  44.4N  115.1W ML=2.4  EMSC   SOUTHERN IDAHO

O: 13NOV2020 16:16:02  44.4N  115.2W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 13NOV2020 08:03:48  44.5N  115.2W ML=2.3  EMSC   SOUTHERN IDAHO

O: 13NOV2020 08:25:45  44.8N  115.8W Ml=2.1  EMSC   SOUTHERN IDAHO

O: 13NOV2020 17:57:00  44.3N  115.2W Ml=3.5  EMSC   SOUTHERN IDAHO               

P: 12NOV2020 128703    44.5N  115.2W 2.0-3.8 AAAAA  Montana/Idaho              

 

 

An earthquake of M 5.3-5.4 shook the region near Mina in western Nevada today. NEIC reported it was felt with maximum intensity IV in Benton, California and II-III within about 200 km in Nevada and California at Luning, Silverpeak, Gabbs, Goldfield, Hawthorne, Round Mountain, Nevada and in California in Bishop, Big Pine and Lee Vining. A number of moderate aftershocks were also felt in western Nevada. No major damage was reported. This activity began with a foreshock of M 2.9 within minutes of local solar midnight. This swarm is a part of the aftershock series following the M 6.5 on May 15, 2020. A similar M 5.3 hit the area on May 22, 2020 but today's event of M 5.4 is the strongest in the area since mid-May. Forecasts 128385 and 128638 had expected today's earthquake was likely between November 4 and 13 within about 25 km of this epicenter. 

 

Following is a listing of aftershocks of M>=3.0 today in the Nevada area. A more extensive listing of events of M>=2 in the area can be found in the regional

"NEVADA" section of this report.

 

O: 13NOV2020 09:13:51  38.2N  117.8W Mw=5.4  EMSC   NEVADA

O: 13NOV2020 09:15:32  38.2N  117.9W ML=4.1  EMSC   NEVADA

O: 13NOV2020 09:29:23  38.2N  117.8W ML=4.0  EMSC   NEVADA

O: 13NOV2020 09:32:54  38.2N  117.8W ML=3.0  EMSC   NEVADA

O: 13NOV2020 13:39:37  38.2N  117.8W ML=3.2  EMSC   NEVADA

O: 13NOV2020 17:43:23  38.2N  117.8W ml=3.3  EMSC   NEVADA

O: 13NOV2020 21:01:44  38.2N  117.9W ml=3.5  EMSC   NEVADA

P: 13NOV2020 128638    38.2N  117.7W 2.5-5.5 AAAAA  California/Nevada area     

 

An unusually large M 5.3 also occurred today in the Gulf of California off the coast of Sinaloa, Mexico. It occurred within minutes of local solar noon and was probably promoted not only by energy from central California but also by high tidal stresses associated with the upcoming new moon as discussed previously in this summary:

 

"The new moon will arrive on November 15 at 05:07 UT. Longitudes which are antisolar (local solar midnight) are near 75 West while those of sub-solar (local solar noon) are near 105 East longitude. In the west these include the west coast of South and Central America and eastern U.S. and Canada. In the east these include Sumatra and western Indonesia and portions of eastern Asia. These areas are likely to see enhanced seismicity during the next week. A strong earthquake in South America and/or western Indonesia is likely during this time. Other areas can also be triggered by high tidal stresses associated with the new moon, but these areas are less likely than those identified here. Near the last new moon on October 16, earthquakes of M>=5.5 occurred in Ecuador, Sumatra, Iceland, Atacama, Chile and as an M 7.6 in the Alaska Peninsula. These areas may see enhanced seismicity with the current new moon as well." (November 11-13, 2020)

 

The last earthquake within about 200 km of this epicenter with M>=5.3 was an M 6.1 on May 22, 2020 and prior to that an M 5.5 on December 8, 2000. Most activity at this magnitude level in this area occurs well to the north and west of today's epicenter.  Forecasts 128618 and 128593 had expected this event in  this region was likely in mid-November.

 

NEIC reported this earthquake of M 5.3 in western Mexico  was felt with intensity II-III in the area(s) of  western Mexico. This epicenter is at 106 degrees from the M 7.0 in the Dodecanese Islands of October 30 and may have been promoted by concentrated energy from that source.

 

O: 13NOV2020 19:04:15  22.4N  107.7W Mw=5.3  EMSC   OFF COAST OF SINALOA, MEXICO 

P: 16NOV2020 128618    24.0N  109.0W 3.5-4.8 BBAAA  Gulf of California         

P: 18NOV2020 128593    19.0N  107.0W 3.5-5.1 BCAAA  Coast of Jalisco, Mexico   

 

An earthquake of M 3.8-4.0 occurred today in northern Hawaii Island, Hawaii. NEIC reported it was felt with maximum intensity IV in Honokaa, Kamuela, Paauilo and II-III in Waikoloa, Laupahoehoe, Ookala, Kapaau, Papaaloa, Hawi and Kailua Kona, Hawaii. The last earthquake in the northern portion of the island of Hawaii within about 50 km of this epicenter with M>=4 occurred one year ago on November 11, 2019 with M 4.9. Forecast 128370 had expected today's event was likely in early November.

 

O: 13NOV2020 19:36:11  19.9N  155.5W ML=4.0  EMSC   ISLAND OF HAWAII, HAWAII     

P:  6NOV2020 128370    20.4N  155.1W 4.0-5.3 CAAAA  Hawaii area                

 

MODERATE QUAKE SHAKES WESTERN NEVADA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 12, 2020

 

A series of swarms of earthquakes occurred today in western and southern U.S. These included energetic swarms in the region of western Nevada near Mina including an M 5.4; an energetic swarm in southern Idaho; and several others in southern California and central California as well as two swarms in Arkansas and Oklahoma. Many of these appear to be associated with high tidal stresses with the upcoming new moon. Much of this activity is also at or near 103 degrees from the M 7.0 in the Dodecanese Islands of October 30 as noted in previous issues of this summary:

 

"Areas of Southern and Central California, eastern Mexico and Guatemala and northern South America and Indonesia area near 103 degrees from the M 7.0 epicenter and could see enhanced seismicity due to energy concentration in those areas." (October 31, 2020)

 

The largest these swarms included an earthquake of M 5.3-5.4 which shook the region near Mina in western Nevada today. NEIC reported it was felt with maximum intensity IV in Benton, California and II-III within about 200 km in Nevada and California at Luning, Silverpeak, Gabbs, Goldfield, Hawthorne, Round Mountain, Nevada and in California in Bishop, Big Pine and Lee Vining. A number of moderate aftershocks were also felt in western Nevada. No major damage was reported. This activity began with a foreshock of M 2.9 within minutes of local solar midnight. This swarm is a part of the aftershock series following the M 6.5 on May 15, 2020. A similar M 5.3 hit the area on May 22, 2020 but today's event of M 5.4 is the strongest in the area since mid-May. Forecasts 128385 and 128638 had expected today's earthquake was likely between November 4 and 13 within about 25 km of this epicenter. 

 

O: 12NOV2020 08:22:22  38.2N  118.1W ml=2.4  EMSC   NEVADA

O: 12NOV2020 17:11:48  38.2N  118.1W ML=2.6  EMSC   NEVADA

O: 13NOV2020 09:13:51  38.2N  117.8W Mw=5.4  EMSC   NEVADA

O: 13NOV2020 09:15:32  38.2N  117.9W ML=4.1  EMSC   NEVADA

O: 12NOV2020 07:28:23  38.2N  118.1W ml=2.9  EMSC   NEVADA                       

P:  4NOV2020 128385    37.8N  117.8W 2.5-4.4 CAAAA  California/Nevada area     

P: 13NOV2020 128638    38.2N  117.7W 2.5-5.5 AAAAA  California/Nevada area     

 

Other swarms in  California today occurred in Southern California. One of these extended a series of earthquakes in the area which began in late October. These events are at 103 degrees from the Dodecanese Islands M 7.0 of October 30, and, like other swarms today was probably enhanced by energy from that source. Forecasts 128413 and 128669 expected this activity was likely in early to mid November.

 

O: 13NOV2020 05:51:02  33.2N  115.6W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 13NOV2020 05:56:52  33.2N  115.6W ML=2.7  EMSC   SOUTHERN CALIFORNIA

O: 13NOV2020 05:58:27  33.2N  115.6W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 13NOV2020 08:14:51  33.2N  116.1W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 13NOV2020 03:35:25  33.0N  115.9W Ml=2.4  EMSC   SOUTHERN CALIFORNIA          

P:  4NOV2020 128413    32.9N  115.6W 2.5-4.3 CAAAA  So. California             

P: 14NOV2020 128669    31.9N  116.3W 2.5-4.8 ABAAA  So. California             

 

The earthquake in Nevada followed a swarm in the Ridgecrest, California area. The largest of these occurred near local solar noon and local solar midnight and may have been promoted by high tidal stresses. Forecasts 128415 and 128637 had expected this activity within about 25 km in early to mid-November.

 

O: 12NOV2020 12:59:33  35.7N  117.5W ML=2.1  EMSC   SOUTHERN CALIFORNIA

O: 12NOV2020 19:51:24  35.7N  117.5W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 13NOV2020 06:26:55  35.7N  117.5W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 12NOV2020 10:48:03  36.0N  117.7W Ml=2.1  EMSC   CENTRAL CALIFORNIA

O: 12NOV2020 15:05:28  36.1N  117.9W Ml=2.1  EMSC   CENTRAL CALIFORNIA

O: 12NOV2020 08:54:32  35.7N  117.5W Ml=2.0  EMSC   SOUTHERN CALIFORNIA          

P:  4NOV2020 128415    35.9N  117.7W 2.5-4.3 CAAAA  So. California             

P: 14NOV2020 128637    35.8N  118.1W 2.5-4.4 AAAAA  California/Nevada area     

 

The swarm in southern Idaho today included events of M 3.0, 3.0 and 2.9 as well as a series of smaller events. This continues the strong aftershock sequence of the M 6.5 in the area of March 30, 2020. Forecast 128703 expected today's activity was likely around November 12.

 

O: 13NOV2020 00:41:25  44.3N  115.0W Ml=2.1  EMSC   SOUTHERN IDAHO

O: 13NOV2020 02:24:40  44.3N  115.0W Ml=2.3  EMSC   SOUTHERN IDAHO

O: 13NOV2020 02:48:18  44.3N  115.0W Ml=3.0  EMSC   SOUTHERN IDAHO

O: 13NOV2020 02:48:18  44.3N  115.0W Ml=3.0  EMSC   SOUTHERN IDAHO

O: 13NOV2020 02:59:32  44.3N  115.0W Ml=2.9  EMSC   SOUTHERN IDAHO

O: 13NOV2020 03:01:47  44.3N  115.0W ML=2.3  EMSC   SOUTHERN IDAHO

O: 13NOV2020 03:42:35  44.3N  115.0W ML=2.4  EMSC   SOUTHERN IDAHO

O: 13NOV2020 08:03:48  44.5N  115.2W ML=2.3  EMSC   SOUTHERN IDAHO

O: 13NOV2020 08:25:45  44.8N  115.8W Ml=2.1  EMSC   SOUTHERN IDAHO

O: 12NOV2020 11:11:32  44.3N  115.1W Ml=2.0  EMSC   SOUTHERN IDAHO               

P: 12NOV2020 128703    44.5N  115.2W 2.0-3.8 AAAAA  Montana/Idaho              

 

The activity in Arkansas included two epicenters. The largest activity was near the Missouri border and included quakes of M 2.2, 2.3, 2.4 and 2.5. These follow a similar but smaller swarm on October 26-28 which also included an event of M 2.5. Forecasts 128401 and 128655 had expected today's event  in the area in early November.

 

O: 12NOV2020 08:15:11  36.4N   90.8W Md=2.4  EMSC   ARKANSAS

O: 12NOV2020 09:20:04  36.4N   90.8W Md=2.3  EMSC   ARKANSAS

O: 12NOV2020 10:31:03  36.4N   90.9W Md=2.2  EMSC   ARKANSAS

O: 12NOV2020 07:38:36  36.4N   90.8W Md=2.5  EMSC   ARKANSAS                     

P:  8NOV2020 128401    36.5N   89.6W 2.0-3.8 BAAAA  New Madrid area            

P: 14NOV2020 128655    36.0N   89.0W 2.0-3.8 AABAA  New Madrid area            

 

O: 12NOV2020 07:40:34  36.4N   93.0W mb=2.1  EMSC   ARKANSAS                     

P: 14NOV2020 128678    35.0N   92.0W 2.0-3.8 ABAAA  Southeast U.S.             

 

The strongest earthquake in the world today was an M 5.7 in the Macquarie Island region south of New Zealand. It was not reported felt in this remote area. The last earthquake within about 300 km of this epicenter with M>=5.7 in the Macquarie Islands area occurred March 1, 2019 with M 5.8 and prior to that on September 8, 2016. This epicenter is at 144 degrees from the Dodecanese Islands M 7.0 of October 30 and was probably promoted by energy from that source.

 

O: 13NOV2020 09:12:46  53.0S  159.9E Mw=5.7  EMSC   MACQUARIE ISLAND REGION      

 

Other moderate earthquakes under the world's oceans occurred today in the western Indian-Antarctic Ridge. This earthquake is the largest within about 300 km of this epicenter since an M 5.1 on December 6, 2019 and a similar M 5.1 on September 23, 2018. Forecast 128544 had expected today's event was likely around November 11.

 

O: 13NOV2020 04:35:43  49.6S  117.2E mb=5.0  EMSC   WESTERN INDIAN-ANTARCTIC RIDGE

P: 11NOV2020 128544    49.0S  122.0E 4.0-5.3 AACAA  So. of Australia           

 

An M 4.9 also occurred in the area south of Africa near the antipode of the  M 7.6 in the Alaska Peninsula of October 19. It was not reported felt in  this remote area. Forecast 128545 had expected today's event within about 200 km of this epicenter was likely in early November.

 

O: 12NOV2020 11:10:05  52.6S   28.0E mb=4.9  EMSC   SOUTH OF AFRICA              

P:  5NOV2020 128545    51.0S   29.0E 4.0-5.4 CBAAA  Atlantic-Indian Ridge      

 

QUIET DAY IN GLOBAL SEISMICITY; UNUSUAL QUAKE IN KUWAIT

 

EARTHQUAKE SUMMARY FOR NOVEMBER 11, 2020

 

A moderate earthquake of M 4.6 shook areas of Kuwait today with maximum intensity up to IV. It was reported felt within about 50 km of the epicenter.

This is the strongest earthquake within about 200 km of Kuwait since an M 4.7 on July 20, 2010 but the last such event within Kuwait of equal or greater magnitude was an M 4.6 on September 18, 1997. The strongest earthquake in the general area in the past 30 years was an M 5.3 on April 22, 1995. Much of the activity in this area may be related to oil extraction as with the exception of the M 5,3 in April, 1995 all such events have had magnitudes of M 4.6-4.8, typical of extraction-induced events. Forecast 128417 had expected today's activity was likely to the north around November 11.

 

O: 11NOV2020 14:56:23  28.9N   47.7E mb=4.6  EMSC   KUWAIT-SAUDI ARABIA BORDER REG

P: 11NOV2020 128417    34.0N   49.0E 3.8-5.1 ACAAA  So. Iran                   

 

Moderate earthquakes also continued today in the region of Northern Macedonia following the M 5.0 there reported on in the previous issue of this summary. An M 4.9 was felt with intensity IV in Rostusa and Tetovo and II-III in Kicevo, Brod, Skopje, Bitola, Veles, and as far as Kosovo, Serbia and Montenegro. In the previous issue of this summary this activity had been addressed as:

 

"A moderate M 5.0 shook much of Macedonia today. NEIC reported maximum intensity V in Macedonia at Gostivar, Zajas, Cegrane, Kicevo, Debar, Bogovinje and in Peshkopi, Albania. It was also felt with intensity III-IV in Macedonia at Mavrovi, Dolna and Rostusa, Gostivar. This continues elevated seismicity in eastern Europe following the M 7.0 in the Dodecanese Islands of Greece on October 30. The last earthquake within about 150 km of this Macedonian event with M>=5.0 occurred on January 28, 2020. That event was an aftershock in Albania of the M 6.4 of November 26, 2019.  The last such event in Macedonia was an M 5.1 on August 11, 2018. Forecast 128458 had expected today's event was likely in this area around November 8." (November 11, 2020)

 

O: 11NOV2020 12:26:37  41.7N   20.8E ML=3.7  EMSC   REPUBLIC OF NORTH MACEDONIA

O: 11NOV2020 14:25:13  41.7N   20.7E ML=4.9  EMSC   REPUBLIC OF NORTH MACEDONIA

O: 11NOV2020 15:43:22  41.7N   20.8E ML=3.8  EMSC   REPUBLIC OF NORTH MACEDONIA

O: 11NOV2020 10:59:37  41.7N   20.8E ML=3.8  EMSC   REPUBLIC OF NORTH MACEDONIA  

P:  9NOV2020 128458    40.0N   20.0E 3.0-4.8 ABAAA  Romania/NW Turkey          

 

The strongest seismicity in the world today was a pair of moderate quakes in southern Taiwan with M 5.3 and 5.0. CWB reported these earthquakes were felt with intensity III in Taitung,  and I in Pingtung and Kaohsiung counties, Taiwan. The last earthquake reported in southern Taiwan within about 100 km of these epicenters with M>=5.3 was an M 5.9 on April 10, 2020 and prior to that an M 5.7 on July 27, 2019. Forecast 128376 had expected today's activity was likely in this area around November 10. Tropical Storm Vamco passed south of Taiwan today and may have helped trigger this activity. The area has been subject to several strong storms in the past week.

 

O: 11NOV2020 21:35:35  21.6N  121.8E mb=4.8  EMSC   TAIWAN REGION                

O: 11NOV2020 21:35:34  21.6N  121.9E ML=5.0  TAI    Hualien, Taiwan              

O: 11NOV2020 21:33:27  21.6N  121.8E ML=5.3  TAI    Hualien, Taiwan              

O: 11NOV2020 21:33:27  21.6N  121.9E Mw=5.0  EMSC   TAIWAN REGION                

P: 10NOV2020 128376    21.0N  120.0E 4.0-5.3 AABAA  Taiwan                     

 

An unusually large M 3.4 shook regions of Central California south of San Francisco today. It was followed by an M 3.0 aftershock, also felt in that region. NEIC reported this earthquake of M 3.0 in Central California  was felt with intensity II-III in the area(s) of  Central California at San Juan Bautista, Salinaas, Hollister, Marina, Seaside, Pacific Grove and Carmel.  This was an aftershock of an M 3.4 which hit the same area and was felt with intensity II-III in Gilroy, Salinas, Moss Landing, Castroville, Aromas, and San Juan Bautista. The last earthquake of significantly larger magnitude within about 75 km of today's epicenter was an M 3.7 on February 13, 2020. Similar earthquakes of M 3.4-3.5 within about 100 km of today's event occurred on October 14 and September 27 and 28, 2020. Forecast 128388 had expected today's activity within about 10 km of this epicenter was likely around November 6. This epicenter is at 100 degrees from the M 7.0 in the Dodecanese Islands, Greece of October 30 and was probably promoted by strong energy concentration in the area from that event as discussed in previous issues of this summary:

 

"Areas of Southern and Central California, eastern Mexico and Guatemala and northern South America and Indonesia area near 103 degrees from the M 7.0 epicenter and could see enhanced seismicity due to energy concentration in those areas." (October 31, 2020)

 

Other earthquakes today at this distance from the Dodecanese Islands occurred in Chiapas, Guatemala and Oaxaca, Mexico and in western Nevada. These areas may see further enhanced seismicity with the coming new moon.

 

O: 11NOV2020 20:48:32  36.8N  121.5W Md=3.0  EMSC   CENTRAL CALIFORNIA           

O: 11NOV2020 20:26:59  36.8N  121.5W Ml=3.4  EMSC   CENTRAL CALIFORNIA           

P:  6NOV2020 128388    36.9N  121.5W 2.5-4.3 BAAAA  Central California         

 

STRONG EARTHQUAKE IN FIJI ISLANDS

 

EARTHQUAKE SUMMARY FOR NOVEMBER 10, 2020

 

The strongest earthquake in the world today was an M 6.0 in the Fiji Islands. It was followed by an M 4.6 aftershock. It was not reported felt in this remote area. This is the strongest earthquake within about 150 km of this epicenter since an M 6.6 on September 1, 2019. Forecasts 128512 and 128527 had expected today's activity was likely in early November in this area. This event is located at 144 degrees from the M 6.8 in the Central Mid-Atlantic of September 18, 2020 and was probably promoted by energy from that source.

 

O: 11NOV2020 05:36:46  19.9S  176.1W mb=4.6  EMSC   FIJI REGION

O: 11NOV2020 00:48:42  19.8S  177.5W Mw=6.0  EMSC   FIJI REGION                  

P:  4NOV2020 128512    19.0S  178.0W 4.0-5.4 CAAAA  Tonga Islands              

P:  7NOV2020 128527    20.0S  179.0W 4.0-5.3 BABAA  Tonga Islands              

 

An M 5.6 in the Volcano Islands today was an aftershock of the M 5.8 in this region of November 7. It is the second largest earthquake in the Volcano Islands in the past year. Forecast 128378 had expected today's activity within about  150 km of this epicenter in the Volcano Islands was likely around November 7. When the M 5.8 occurred on November 7, this summary noted it as:

 

 

"A moderately strong earthquake of M 5.8 occurred today in the Volcano Islands of Japan. It was not reported felt in this area. Tropical Depression 20W passed over this epicenter in late October and may have helped set this earthquake up.

This is the strongest earthquake within about 200 km of this epicenter since an M 6.4 on December 22, 2010." (November 7, 2020)

 

O: 11NOV2020 05:17:59  25.5N  142.8E Mw=5.6  EMSC   VOLCANO ISLANDS, JAPAN REGION

P:  7NOV2020 128378    24.0N  143.0E 4.0-5.3 BBAAA  Volcano Islands            

 

A moderate M 5.0 shook much of Macedonia today. NEIC reported maximum intensity V in Macedonia at Gostivar, Zajas, Cegrane, Kicevo, Debar, Bogovinje and in Peshkopi, Albania. It was also felt with intensity III-IV in Macedonia at Mavrovi, Dolna and Rostusa, Gostivar. This continues elevated seismicity in eastern Europe following the M 7.0 in the Dodecanese Islands of Greece on October 30. The last earthquake within about 150 km of this Macedonian event with M>=5.0 occurred on January 28, 2020. That event was an aftershock in Albania of the M 6.4 of November 26, 2019.  The last such event in Macedonia was an M 5.1 on August 11, 2018. Forecast 128458 had expected today's event was likely in this area around November 8.

 

O: 11NOV2020 03:54:14  41.6N   20.8E Mw=5.0  EMSC   REPUBLIC OF NORTH MACEDONIA

O: 11NOV2020 04:02:15  41.6N   20.7E ML=2.2  EMSC   REPUBLIC OF NORTH MACEDONIA

O: 11NOV2020 05:23:48  41.7N   20.8E ML=3.0  EMSC   REPUBLIC OF NORTH MACEDONIA  

P:  9NOV2020 128458    40.0N   20.0E 3.0-4.8 ABAAA  Romania/NW Turkey          

 

 

Two earthquakes of M 4.3 occurred in the U.S. or Canada today. These were reported in the Andreanof Islands, Aleutians and in the Queen Charlotte Islands of Canada. They were not reported felt in these areas. The last event of M>=4.3 within about 100 km of this epicenter in the eastern Andreanof Islands was an M 4.7 on November 5, 2019. Forecast 128469 had expected this event was likely around November 5.

 

O: 10NOV2020 19:45:08  52.6N  172.4W mb=4.3  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  5NOV2020 128469    52.2N  171.5W 3.5-4.8 BAAAA  Andreanoff Isls, Aleutians 

 

The last earthquake in the Queen Charlotte Islands area within about 100 km of today's event with M>=4.3 was an M 4.6 on February 14, 2020. Forecast 128470 had expected today's activity in this area was likely around November 9.

 

O: 11NOV2020 01:10:37  51.3N  131.0W mb=4.3  EMSC   QUEEN CHARLOTTE ISLANDS REGION

O: 10NOV2020 08:51:37  53.1N  132.8W ML=2.8  EMSC   QUEEN CHARLOTTE ISLANDS REGION

P:  9NOV2020 128470    52.0N  132.0W 3.0-4.9 ABAAA  British Colombia           

 

MODERATE QUAKE IN NEW IRELAND, PNG

 

EARTHQUAKE SUMMARY FOR NOVEMBER 9, 2020

 

The only event of M>5.0 in the world today was an M 5.6 in the region of New Ireland, P.N.G. NEIC reported this earthquake of M 5.5-5.6 in New Britain, PNG was felt with intensity II-III in the area(s) of New Britain, PNG at Kokopo.

The last earthquake with M>=5.6 within about 150 km of this epicenter was an

M 7.5 on May 14, 2019 about 100 km southwest of today's epicenter. An M 6.0 also occurred in this region on May 17, 2019 - an aftershock of the M 7.5 Forecast 128328 expected today's event in this area was possibly around November 10. This epicenter is within about 300 km of the antipode of the M 6.8 in the Central Mid-Atlantic of September 18 and was probably promoted by focused energy from that event at the antipode.

 

O:  9NOV2020 16:45:33   3.7S  153.4E Mw=5.6  EMSC   NEW IRELAND REGION, P.N.G.   

P: 10NOV2020 128328     5.0S  152.0E 4.0-5.3 ABBAA  New Britain                

 

 

The strongest earthquake in the U.S. or Canada today was an M 4.0 and 4.1 in the Alaska Peninsula aftershock zone. These are typical aftershocks at this time but follow several days of elevated seismicity in the area. Forecasts 128467 had expected this activity was likely around November 8.

 

O: 09NOV2020 22:01:35  54.2N  159.9W mb=4.0  EMSC   SOUTH OF ALASKA

O:  9NOV2020 08:54:18  54.4N  159.7W mb=4.1  EMSC   SOUTH OF ALASKA              

P:  8NOV2020 128467    54.8N  160.7W 3.5-4.8 AAAAA  Alaska Peninsula           

 

A series of light earthquakes occurred in the eastern U.S. and Canada today. These were located in Virginia (M 2.8, 2.8); southern Ontario, Canada (M 2.5) and Southern Quebec (M 2.5). A series of light earthquakes were also located in eastern Canada. The activity in Virginia is the first within about 100 km of this epicenter in Virginia during the past year. An M 5.1 occurred about 100 km southeast of today's epicenter on August 9 with an M 3.2 on October 25 and an M 2.9 on October 1, 2020. Forecast 128398 had expected activity in this area was possible around November 5. This may have been related to landfall of Tropical Storm Eta in Florida yesterday.

 

O: 09NOV2020 07:35:35  37.2N   81.8W mb=2.8  EMSC   VIRGINIA

O:  9NOV2020 08:17:57  37.2N   81.8W mb=2.8  EMSC   VIRGINIA                      

P:  5NOV2020 128398    35.0N   83.0W 2.0-3.9 BCAAA  Kentucky/Tennessee/NC      

 

The earthquake of M 2.5 in Southern Ontario, Canada was the largest reported within about 100 km of that epicenter since an M 2.5 on July 29, 2012.  Forecast 128455 had expected activity to the northwest of this was likely around November 9.

 

O:  9NOV2020 16:33:25  44.6N   79.1W ML=2.5  EMSC   SOUTHERN ONTARIO, CANADA     

P:  9NOV2020 128455    46.0N   81.0W 2.0-3.8 ABBAA  Ohio/Lake Erie             

 

The M 2.5 in Southern Quebec was the largest within about 100 km of this epicenter since an M 3.9 on May 9, 2020 and prior to that an M 3.7 on July 13, 2019.  Forecasts 128448 and 128447 had expected this activity was likely in early November.

 

O: 10NOV2020 01:15:00  47.1N   76.6W ML=2.5  EMSC   SOUTHERN QUEBEC, CANADA      

P:  2NOV2020 128448    45.7N   75.2W 2.0-3.9 CBBAA  New York State             

P:  8NOV2020 128447    46.2N   72.7W 2.0-3.8 AACAA  New England                

 

 

LIGHT EARTHQUAKE IN MASSACHUSETTS SHAKES ENTIRE EASTERN U.S., CANADA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 8, 2020

 

An earthquake of M 3.6 was widely felt in New England and throughout the eastern U.S. and Canada today. NEIC reported this quake was felt with maximum intensity V in Massachusetts at Ne Bedford and IV in South Dartmouth, Fairhaven, Westport, North Dartmouth, Little Compton, Mattapoisett and throughout much of northeastern U.S. including the states of Maine, New York, Pennsylvania, Vermont, New Jersey, New Hampshire, Washington, DC, Maryland, Virginia, West Virginia, North Carolina, Ohio, Michigan, Kentucky, South Carolina, Indiana, Tennessee, Illinois, Georgia, Iowa, Florida, Rhode Island, Missouri, Arkansas, Minnesota, Oklahoma, Texas, New York, Delaware, Connecticut, and others. Ontario, Nova Scotia, Canada. No major damage was reported with this earthquake.

This earthquake occurred as Tropical Storm Eta was making landfall in southern Florida. Motions of the eastern U.S. from this landfall event may have helped promote this earthquake. Other areas which may be affected by Eta include North Carolina and Virginia and these areas may still see enhanced seismicity in the next several days. Two other earthquakes of M 3.6 have hit within about 200 km of today's epicenter in the past 30 years - on October 2, 1994 and July 22, 2003. Forecast 128443 had expected today's earthquake in this area was likely around November 8.

 

O:  8NOV2020 14:10:06  41.5N   70.9W Mw=3.6  EMSC   SOUTHERN NEW ENGLAND         

P:  8NOV2020 128443    43.0N   70.0W 2.0-3.9 ABAAA  Maine                      

 

An M 3.7 in the region of Colorado  was the strongest event reported in the U.S. or Canada today. This is the strongest earthquake in northern Colorado within about 150 km of this epicenter since an M 4.5 on March 4, 2019 and prior to that on January 24, 2013 with M 3.9. Forecast 128394 had expected today's event within about 100 km of this epicenter was likely around November 11.

 

O:  8NOV2020 11:19:56  38.3N  108.9W ML=3.7  EMSC   COLORADO                     

P: 11NOV2020 128394    39.2N  108.4W 2.0-3.8 BAAAA  Colorado area              

 

An earthquake of M 2.8 also occurred today in central Colorado several hours after the M 3.7. The last such earthquake within about 50 km of this epicenter was an M 3.7 about 30 km south of today's epicenter on September 1, 2019. Forecast 128393 had expected this earthquake in this area was likely around November 8.

 

NEIC reported this earthquake of M 2.8 in Central Colorado  was felt with intensity II-III in the area(s) of  Central Colorado at Walsenburg.

 

O:  8NOV2020 19:18:50  37.6N  104.8W mb=2.8  EMSC   COLORADO                     

P:  8NOV2020 128393    37.1N  104.7W 2.0-3.9 AAAAA  Colorado area              

 

MODERATE EARTHQUAKE SHAKES ANCHORAGE AREA, ALASKA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 7, 2020

 

The strongest seismicity in the U.S. or Canada today occurred in Alaska where

an M 5.3 hit the Anchorage area; an M 4.4 in the Near Islands and an M 4.7 in the Andreanof Islands. The series of moderate earthquakes shook the area north of Anchorage, Alaska today including several of M>=4. NEIC reported this activity was felt with intensity IV in Alaska at Willow and Elmendorf AFB (IV) and in Wasilla, Chugiak and Anchorage. The largest of today's events was an M 5.0 felt with intensity IV within about 50 km of the epicenter. This appears to be the strongest aftershock of the November 30, 2018 M 7.0 near Anchorage since the mainshock.  Forecast 128486 had expected today's event within this aftershock zone was likely around November 5.  This epicenter is located at 104 degrees from the M 6.8 in the Central Mid-Atlantic of September 18 and was probably promoted by concentrated energy from that source.

 

O: 07NOV2020 15:03:53  61.5N  149.9W mb=4.5  EMSC   SOUTHERN ALASKA

O: 07NOV2020 12:27:27  61.6N  149.9W mb=4.4  EMSC   SOUTHERN ALASKA

O:  7NOV2020 12:23:10  61.5N  149.9W mb=5.3  EMSC   SOUTHERN ALASKA              

P:  5NOV2020 128486    60.9N  147.4W 3.2-4.8 AAAAA  Central Alaska             

 

The strongest earthquake in the world today was an M 6.2 in the region of Samoa. NEIC reported it was felt with intensity IV in Samoa at Apia and American Samoa and III in Western American, Samoa and Vaimalau Mua, Wallis and Futuna.  The last of equal or stronger magnitude in the area of Samoa was an M 6.8 on November 4, 2017 and an M 6.0 on March 30, 2015. Forecast 128507 had expected this earthquake was likely within about 50 km  of this event around November 8. This epicenter is located at 144 degrees from the M 6.8 in the Central Mid-Atlantic of September 18 and was probably promoted by concentrated energy from that source. A moderate series including an M 5.2, 4.8 and 4.6 also occurred at this distance from the Central mid-Atlantic in the Izu Islands of Japan today.

 

O:  7NOV2020 09:27:06  15.4S  173.6W Mw=6.2  EMSC   TONGA                        

P:  8NOV2020 128507    15.0S  174.0W 4.0-5.3 AAAAA  Samoa Islands              

 

The last earthquake in the Izu Islands within about 200 km of the M 5.2 there today was an M 5.9 on October 3, 2020 and prior to that an M 5.3 on December 20, 2019. Forecast 128407 expected today's activity was likely around November 7.

This epicenter is near the fourth node (90 degrees) from the Dodecanese Islands

M 7.0 of October 30 and may have promoted by energy from that source.

 

O: 07NOV2020 21:30:43  32.4N  141.9E Mw=5.2  EMSC   IZU ISLANDS, JAPAN REGION

O: 08NOV2020 02:59:37  32.4N  141.6E mb=4.6  EMSC   IZU ISLANDS, JAPAN REGION

O:  7NOV2020 08:06:53  32.4N  141.6E mb=4.8  EMSC   IZU ISLANDS, JAPAN REGION    

P:  7NOV2020 128407    33.0N  140.0E 4.0-5.3 AAAAA  Off East Coast Honshu      

 

STRONG QUAKES IN SOUTH SHETLAND IS; TONGA/SAMOA

 

EARTHQUAKE SUMMARY FOR NOVEMBER 6, 2020

 

A series of moderately strong to strong earthquakes occurred today. These included an M 5.9 in Tonga/Samoa; an M 5.8 in the Volcano Islands, Japan; an M 5.6 in northern Japan, two of M 5.4 in Taiwan; and the strongest of the day – an M 6.0 in the South Shetland Islands. This event is the strongest in the current series of moderate quakes in the South Shetland Islands and the strongest in the area of about 500 km about this epicenter since an M 6.6 and 6.0 about 400 km northeast of this on  January 15, 2012. The only other such event in the region in the past 30 years was an M 6.1-6.2 on June 17, 1992. Forecast 128550 had expected today's event within about 100 km of this epicenter was likely around November 4.

 

O:  6NOV2020 23:49:22  62.2S   58.2W Mw=6.0  EMSC   SOUTH SHETLAND ISLANDS       

P:  4NOV2020 128550    61.0S   58.0W 4.0-5.4 ABAAA  Southern Shetland Islands  

 

An earthquake of M 5.9 also occurred today in the region of Samoa. NEIC reported it was felt with intensity IV in Samoa at Apia and American Samoa and III in Western American, Samoa and Vaimalau Mua, Wallis and Futuna. A similar M 5.9 hit this area on October 25, 2020 but the last of stronger magnitude in the area was an M 6.1 on July 18, 2020 and an M 6.0 on March 17, 2020. Forecast 128507 had expected this earthquake was likely within about 50 km of this event around November 8.

 

O:  7NOV2020 09:27:06  15.4S  173.6W Mw=5.9  EMSC   TONGA                         

P:  8NOV2020 128507    15.0S  174.0W 4.0-5.3 AAAAA  Samoa Islands              

 

A moderately strong earthquake of M 5.8 occurred today in the Volcano Islands of Japan. It was not reported felt in this area. Tropical Depression 20W passed over this epicenter in late October and may have helped set this earthquake up.

This is the strongest earthquake within about 200 km of this epicenter since an M 6.4 on December 22, 2010. Forecast 128378 had expected today's event in this region was likely around November 7.

 

O:  7NOV2020 01:10:33  25.6N  143.6E Mw=5.8  EMSC   VOLCANO ISLANDS, JAPAN REGION

P:  7NOV2020 128378    24.0N  143.0E 4.0-5.3 ABAAA  Volcano Islands            

 

An earthquake of M 5.0-5.4 hit the area of Taiwan and was followed by a similar event several hours later. CWB reported this earthquake was felt with intensity IV in Taitung, III in Hualien and Tainan; II in Pingtung, Kaohsiung, Chiayi, Yunlin, Changhua, Nantou, Taichung and Yilan Counties, Taiwan. NEIC reported this earthquake of M 4.8 in Taiwan  was felt with intensity II-III in the area(s) of  Taiwan at Taipei. It was followed by an aftershock of M 5.4 several hours later. This activity was probably triggered by stresses associated with the passage of Tropical Storm Atsani which passed near this epicenter at the time of these two earthquakes.

 

"Tropical Storm Atsani continued north of the northern  Philippines today with winds up to 55 kts. This system is moving to the west and north.  It may affect the region of the northern Philippines and Taiwanese seismicity in the next several days but is now expected to pass north of the Philippines and south of Taiwan." (November 5-6, 2020)

 

The last earthquakes in Taiwan of M>=5.4 occurred on May 3 (M 5.7); June 13 (M 5.4) and February 15, 2020 (M 5.7). Forecasts 128376 had expected moderate earthquakes in Taiwan within about 100 km of these epicenter were likely in early November.

 

O:  5NOV2020 18:36:11  22.5N  121.5E mb=5.0  EMSC   TAIWAN REGION                

O:  5NOV2020 18:36:12  22.6N  121.4E ML=5.4  TAI    Hualien, Taiwan              

P:  5NOV2020 128376    22.0N  122.0E 4.0-5.3 AAAAA  Taiwan                     

 

CWB reported the second  earthquake of M 5.4 was felt with intensity III in Pingtung, Hualien, Changhua; II in Nantou, Kaohsiung, Yilan, Taichung, Miaoli, Tainan, Chiayi, and I in Yunlin, Pingtung, Taipei, Hsinchu, Taoyuan Counties, Taiwan.

 

O:  6NOV2020 01:40:18  23.1N  122.1E ML=5.4  TAI    Hualien, Taiwan              

O:  6NOV2020 01:40:17  23.1N  122.1E mb=5.0  EMSC   TAIWAN REGION                

P:  8NOV2020 128376    23.0N  122.0E 4.0-5.3 AAAAA  Taiwan                     

 

Earthquakes of M 5.6 and 5.2 also occurred in the region of Hokkaido, Japan today. These events were noted in the previous issue of this report as:

 

"The strongest earthquake in the world today was an M 5.6-5.7 off the coast of Northern Honshu and Hokkaido, Japan. It was reported with intensity IV in Hokkaido at Hachinohe and in Misawa, Aomori, Japan. No damage was reported. The last earthquake within about 200 km of this epicenter with M>=5.7 was an M 6.1 on August 28, 2019. An M 5.6 also occurred about 200 km northeast of this with M 5.6 on May 30, 2020. Forecast 128438 had expected today's event was likely around November 7." (November 6, 2020)

 

O: 06NOV2020 17:16:53  40.9N  143.4E Mw=5.2  EMSC   OFF EAST COAST OF HONSHU, JAPAN

O: 06NOV2020 08:56:37  41.0N  143.2E Mw=5.6  EMSC   OFF EAST COAST OF HONSHU, JAPAN

O: 06NOV2020 16:14:28  41.0N  143.3E mb=4.6  EMSC   OFF EAST COAST OF HONSHU, JAPAN

O:  6NOV2020 09:17:08  40.9N  143.2E mb=4.9  EMSC   OFF EAST COAST OF HONSHU, JAPA

P:  7NOV2020 128438    40.0N  142.0E 3.5-5.3 AAAAA  Hokkaido, Japan            

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the aftershock area of southern Idaho of the M 6.5 event of March 31. NEIC reported this earthquake of M 4.0-4.4 in Southern Idaho  was felt with intensity II-III in the area(s) of  Southern Idaho at Garden City, Stanley, Boise, Hailey and in Superior, Montana. A similar aftershock in the area was registered on September 8, but the last of larger magnitude was an M 4.6 on June 25, 2020. The only other aftershock of M>4.4 occurred on April 1, 2020 on April 1, 2020.  Forecast 128445 had expected today's event was likely around November 4.

 

O: 06NOV2020 19:33:04  44.3N  115.2W Ml=3.0  EMSC   SOUTHERN IDAHO

O: 06NOV2020 19:41:37  44.3N  115.2W Ml=2.2  EMSC   SOUTHERN IDAHO

O: 06NOV2020 20:22:10  44.3N  115.2W ML=2.8  EMSC   SOUTHERN IDAHO

O: 06NOV2020 20:36:09  44.3N  115.2W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 07NOV2020 08:00:22  44.3N  115.2W ML=2.7  EMSC   SOUTHERN IDAHO

O: 07NOV2020 08:12:48  44.3N  115.1W ML=2.7  EMSC   SOUTHERN IDAHO

O:  6NOV2020 19:29:36  44.3N  115.2W Ml=4.4  EMSC   SOUTHERN IDAHO               

P:  4NOV2020 128445    44.4N  115.1W 2.0-3.8 AAAAA  Montana/Idaho              

 

The strongest earthquake in Alaska today was an M 3.7 aftershock in the Alaska Peninsula zone following the M 7.5 on October 19. This follows an M 5.1 yesterday in the area, one of the strongest since the mainshock as noted in the previous issue of this summary:

 

 

"The strongest earthquake in the U.S. or Canada today was an M 5.1 in the  Alaska Peninsula aftershock south of Alaska. There have been no earthquakes in the aftershock zone of M>5.1 since an M 5.6 on October 20, 2020 eight hours after the M 7.6 on October 19. Forecast 128467 had expected today's event  was likely around November 2." (November 6, 2020)

 

O:  6NOV2020 09:05:28  54.1N  159.8W ml=3.7  EMSC   SOUTH OF ALASKA               

P:  2NOV2020 128467    54.8N  159.7W 3.5-4.8 BAAAA  Alaska Peninsula           

P:  5NOV2020 128467    54.8N  158.7W 3.5-4.8 AAAAA  Alaska Peninsula           

 

 

O:  6NOV2020 15:39:52  39.9N   88.3W Md=2.4  EMSC   ILLINOIS                     

P: 11NOV2020 128454    40.0N   84.0W 2.0-3.9 BACAA  Ohio/Lake Erie             

P: 31OCT2020 128184    36.9N   89.2W 2.0-3.8 CCAAA  New Madrid area            

 

MODERATE EARTHQUAKE SHAKES NORTHERN JAPAN

 

EARTHQUAKE SUMMARY FOR NOVEMBER 5, 2020

 

The strongest earthquake in the world today was an M 5.6-5.7 off the coast of Northern Honshu and Hokkaido, Japan. It was reported with intensity IV in Hokkaido at Hachinohe and in Misawa, Aomori, Japan. No damage was reported.

The last earthquake within about 200 km of this epicenter with M>=5.7 was an M 6.1 on August 28, 2019. An M 5.6 also occurred about 200 km northeast of this with M 5.6 on May 30, 2020. Forecast 128438 had expected today's event was likely around November 7.

 

O: 06NOV2020 09:17:08  41.0N  143.2E mb=4.9  EMSC   OFF EAST COAST OF HONSHU, JAPAN

O: 05NOV2020 19:42:30  40.1N  140.6E ML=4.2  EMSC   EASTERN HONSHU, JAPAN

O:  5NOV2020 19:51:30  40.0N  140.6E ML=4.1  EMSC   EASTERN HONSHU, JAPAN        

O:  6NOV2020 08:56:37  41.0N  143.2E Mw=5.6  EMSC   OFF EAST COAST OF HONSHU, JAPA

P:  7NOV2020 128438    40.0N  142.0E 3.5-5.3 AAAAA  Hokkaido, Japan            

 

The strongest earthquake in the U.S. or Canada today was an M 5.1 in the  Alaska Peninsula aftershock south of Alaska. There have been no earthquakes in the aftershock zone of M>5.1 since an M 5.6 on October 20, 2020 eight hours after the M 7.6 on October 19. Forecast 128467 had expected today's event was likely around November 2.

 

O: 06NOV2020 09:05:27  54.0N  159.7W mb=4.5  EMSC   SOUTH OF ALASKA

O: 05NOV2020 12:56:30  54.2N  159.9W Mw=5.1  EMSC   SOUTH OF ALASKA

O:  5NOV2020 07:44:15  54.6N  159.7W mb=3.9  EMSC   SOUTH OF ALASKA              

P:  2NOV2020 128467    54.8N  159.7W 3.5-4.8 AAAAA  Alaska Peninsula           

 

 

An M 4.6 also occurred in the South Island, New Zealand today near Christchurch.

GEONET reported this earthquake was felt with moderate intensity in the area of Christchurch, South Island, New Zealand. 7493 felt reports were published including 1922 of weak and 4196 of light shaking; 1270 moderate; 84 strong; 4 severe and 7 extreme shaking in northern South Island. NEIC reported this earthquake of M 3.9 in the Christchurch area, South Island, New Zealand was felt with intensity II-III in the area(s) of the Christchurch area, South Island, New Zealand in Christchurch and Leeston, Canterbury. The last earthquake within about 150 km of Christchurch with M>=4.6 was an M 4.8 on March 1, 2017. Forecast 128542 had expected this earthquake within this area was likely around November 5-6. This epicenter is at 101 degrees from the M 7.5 in the Alaska Peninsula of October 19 and was probably promoted by strongly concentrated energy at this distance from that event.

 

O:  5NOV2020 18:26:16  43.6S  172.4E ML=3.9  EMSC   SOUTH ISLAND OF NEW ZEALAND  

O: 05NOV2020 18:26:17  43.6S  172.4E MS=4.6  GEONET Felt with moderate intensity

P:  5NOV2020 128542    42.0S  172.0E 3.0-4.8 AAAAA  So. Island, N.Z.           

P:  6NOV2020 128542    43.0S  171.0E 3.0-4.9 AAAAA  So. Island, N.Z.           

 

MODERATE QUAKES IN SOUTHEAST PACIFIC

 

EARTHQUAKE SUMMARY FOR NOVEMBER 4, 2020

 

The strongest earthquake in the world today was an M 5.4 in the Southeast Pacific south of Easter Island. It was not felt in this remote area. An M 4.7 also occurred north of this but was also not felt. This is the strongest earthquake in this area within about 300 km of this epicenter since an M 5.7 on May 14, 2020 and prior to that an M 5.8 on September 27, 2019. Forecast 128532 had expected this event was likely around November 6. This epicenter is located at 102 degrees from the M 7.5 in the Alaska Peninsula of October 19, 2020 and at 144 degrees from the Dodecanese Islands event of M 7.0 of October and was probably promoted by concentrated energy from these sources.

 

O:  4NOV2020 12:28:42  35.6S  104.0W Mw=5.4  EMSC   SOUTHEAST OF EASTER ISLAND   

P:  6NOV2020 128532    36.0S   97.0W 4.0-5.4 AACAA  Chile Rise                 

 

The M 4.8 to the north of the M 5.4 in the southeast Pacific today is located about 100 km north of an M 4.7 which occurred on October 30.  But the last earthquake of equal or larger magnitude in this area was an M 4.8 on November 24, 2019. The last of larger magnitude in this area was an M 5.7 on February 14, 2014. Forecast 128522 had expected today's event within about 50 km was likely around November 5. This epicenter is at 144 degrees from the Dodecanese Islands

M 7.0 of October 30 and was probably promoted by energy from that source.

 

O:  5NOV2020 03:34:11  23.5S  114.9W mb=4.8  EMSC   EASTER ISLAND REGION         

P:  5NOV2020 128522    24.0S  115.0W 4.0-5.5 AAAAA  So. East Pacific Rise      

 

The largest earthquake in the U.S. or Canada today was an M 5.0 in the Unimak Island region of Alaska. This epicenter is located west of the activity in the Alaska Peninsula. The only earthquake of larger size in the Unimak Island area during the past year was an M 5.6 on August 13, 2020. Forecast 128480 had expected this activity within about 100 km was likely around November 6.

 

O:  4NOV2020 12:23:45  53.6N  164.7W mb=5.0  EMSC   UNIMAK ISLAND REGION, ALASKA 

P:  6NOV2020 128480    54.5N  163.5W 3.5-4.8 AAAAA  Unimak Islands, Aleutians  

 

The largest earthquake in the U.S. or Canada outside Alaska today was an M 4.7 in Newfoundland and Labrador, Canada. It was not reported felt in this region. The last earthquake within about 500 km of this epicenter with M>=4.5 was an M 4.8 on July 29, 1999, the only such event within this area in the past 30 years. Forecast 128257 had expected this area would be active around October 26. This continues activity in this area which has been occurring over the past several days. This activity is located at the seventh node (52 degrees) from the Alaska Peninsula event of M 7.5 of October 19 and  may have been promoted by energy from this source.

 

O:  4NOV2020 09:35:23  55.1N   59.1W ML=4.7  EMSC   LABRADOR, NFLD. AND LAB., CANA

O: 04NOV2020 09:35:23  55.1N   59.1W MB=4.7  ECAN Makkovik, NL, felt   

O: 04NOV2020 06:52:17  55.0N   59.8W MB=4.5  ECAN OF MAKKOVIK, NL   

O:  4NOV2020 06:52:17  55.0N   59.8W ML=4.4  EMSC   LABRADOR, NFLD. AND LAB., CANA

P: 26OCT2020 128257    61.0N   58.9W 2.5-3.8 CCAAA  Baffin/Davis Strait, Canada

 

An M 3.3 earthquake in Baja California, Mexico today continued the swarm that began there following the Dodecanese Islands M 7.0 of October 30 which is at 103 degrees from this swarm and probably helped promote it. Today's M 3.3 was the largest in the area of California today. Forecast 128413 had expected today's activity around November 3.

 

O:  4NOV2020 21:47:00  31.5N  115.6W ML=2.5  EMSC   BAJA CALIFORNIA, MEXICO      

O:  4NOV2020 08:32:20  31.5N  115.6W ML=3.3  EMSC   BAJA CALIFORNIA, MEXICO      

P:  3NOV2020 128413    32.5N  115.7W 2.5-4.3 AAAAA  So. California             

 

A pair of moderate earthquakes hit in the eastern and northern Caribbean today.

These included an M 4.6 in the Dominican Republic and an M 4.5 in the Martinique Region of the Windward Islands. Islands.  NEIC reported this earthquake of M 4.6 in the Dominican Republic was felt with intensity II-III in the area(s) of the Dominican Republic at Boca de Yuma, Otra Banda, La Altagracia, La Romana, Albonito, Carolina.  The last earthquake of larger magnitude than M 4.6 in the Dominican Republic was an M 4.8 on March 6, 2020. Forecast 128361 had expected today's event within this area around November 6.

 

O:  4NOV2020 17:45:10  18.2N   68.2W mb=4.6  EMSC   MONA PASSAGE, DOMINICAN REPUBL

P:  6NOV2020 128361    18.0N   69.0W 3.4-4.8 AAAAA  Puerto Rico                

 

The earthquake in Martinique was not reported felt. Forecast 128348 had expected this event was likely to the northeast around November 7. This is the largest earthquake within about 150 km of this epicenter since an M 4.6 on August 26, 2020 and prior to that an M 4.8 on January 15, 2020.

 

O:  4NOV2020 18:47:32  14.9N   61.5W mb=4.5  EMSC   MARTINIQUE REGION, WINDWARD IS

P:  7NOV2020 128348    16.0N   60.0W 3.0-4.8 BBBAA  Leeward Islands            

 

 

 

 

 

 

 

 

SERIES OF EARTHQUAKES OCCUR UNDER OCEANS AT HIGH LATITUDES

 

EARTHQUAKE SUMMARY FOR NOVEMBER 3, 2020

 

The strongest series of earthquakes in the world today occurred at high latitude oceanic areas. The largest of these was an M 5.2 in the South Sandwich Islands, but earthquakes in the Arctic area included an M 4.6 in the Reykjanes Ridge and an M 4.9 in the Jan Mayen Island area. In the southern Oceans an M 4.8 occurred in the current swarm in the South Shetland Islands and an M 4.7 in the Balleny Islands, south of New Zealand. The earthquake in the Balleny Islands was at 144 degrees from the Dodecanese Islands and at the third node (120 degrees) from the Alaska Peninsula and was probably promoted by energy from that source. Activity in the South Shetland Islands was also at the third node from the Dodecanese Islands. Activity near 103 degrees from the Dodecanese Islands occurred in the South Sandwich Islands, the Gulf of California, Oaxaca and Chiapas, Mexico, Baja California, and the Mariana Islands among others. None of these were reported felt in these remote areas. Forecasts 128547, 128475, 128550 and 128500 had expected this activity was likely early in November.

 

O:  4NOV2020 01:35:32  55.9S   27.0W mb=5.2  EMSC   SOUTH SANDWICH ISLANDS REGION

P:  1NOV2020 128547    55.0S   28.0W 4.0-5.6 BAAAA  So. Sandwich Islands       

 

O:  3NOV2020 06:10:06  57.7N   33.0W mb=4.6  EMSC   REYKJANES RIDGE              

P:  3NOV2020 128475    59.0N   30.0W 4.0-5.3 ABAAA  North Mid-Atlantic Ridge   

 

O:  3NOV2020 15:02:25  62.2S   58.0W mb=4.8  EMSC   SOUTH SHETLAND ISLANDS       

P:  4NOV2020 128550    61.0S   58.0W 4.0-5.4 ABAAA  Southern Shetland Islands  

 

O:  3NOV2020 08:03:44  62.3S  164.9E mb=4.7  EMSC   BALLENY ISLANDS REGION       

 

O:  3NOV2020 20:22:22  71.5N    3.5W Mw=4.9  EMSC   JAN MAYEN ISLAND REGION      

P:  4NOV2020 128500    71.0N    8.0W 3.5-4.8 AAAAA  Jan Mayen Isl. area        

 

The strongest earthquake in the world today was an M 5.7 in the Fiji Islands. A similar M 5.8 hit this region about 150 km to the southeast on October 22, 2020 and as an M 6.0 to the southwest on July 21, 2020. These are probably related. Today's deep focus earthquake was not reported felt. Forecast 128512 had expected this activity was likely around November 4.

 

O:  3NOV2020 08:18:56  20.0S  177.5W Mw=5.7  EMSC   FIJI REGION                  

P:  4NOV2020 128512    19.0S  178.0W 4.0-5.4 AAAAA  Tonga Islands              

 

 

The strongest earthquake in the U.S. or Canada today occurred in the area south  of Alaska in the Alaska Peninsula aftershock zone. The area within about 150 km  of this epicenter has been quiet during the last several years. An M 5.1 occurred  within about 100 km of this epicenter on February 16, 2019 and an M 5.2 on October 1, 2016. Forecast 128480 had expected today's event was likely in this area around November 3.

 

O:  4NOV2020 03:27:23  52.6N  162.7W Mw=5.0  EMSC   SOUTH OF ALASKA              

P:  3NOV2020 128480    52.5N  163.7W 3.5-4.8 AAAAA  Unimak Islands, Aleutians  

 

The largest earthquake in the U.S. or Canada outside Alaska today was an M 4.4-4.5 in Newfoundland and Labrador, Canada. It was not reported felt in this region. The last earthquake within about 500 km of this epicenter with M>=4.5 was an M 4.8 on July 29, 1999, the only such event within this area in the past 30 years. Forecast 128257 had expected this area would be active around October 26.

 

O: 04NOV2020 06:52:17  55.0N   59.8W MB=4.5  ECAN OF MAKKOVIK, NL   

O:  4NOV2020 06:52:17  55.0N   59.8W ML=4.4  EMSC   LABRADOR, NFLD. AND LAB., CANA

P: 26OCT2020 128257    61.0N   58.9W 2.5-3.8 CCAAA  Baffin/Davis Strait, Canada

 

An M 4.3 also occurred in northwestern Canada near the Prince Patrick Island area of the Northwest Territory and Mould Bay. It was not reported felt in this remote area. A swarm of quakes in the area occurred in October and November, 2008 included two earthquakes of M 5.7 but the only event of M>=4.3 in the past 12 years was an M 4.5 on August 3, 2013. Forecast 128498 had expected this event within about 150 km of this epicenter was likely in early November.

 

O: 03NOV2020 09:05:13  77.8N  115.3W MB=4.3  ECAN Mould Bay, NT   

O:  3NOV2020 09:05:13  77.8N  115.3W ML=4.3  EMSC   PRINCE PATRICK ISL., NWT, CANA

P:  7NOV2020 128498    79.0N  114.0W 4.0-5.4 BBAAA  Arctic Ocean Region        

 

The swarm in Baja California continued today with the largest event to date of M 3.7 and 3.3. This swarm began two days ago and was noted in this summary as:

 

 

"A series of light earthquakes shook the region of Baja California today. This swarm included earthquakes of M 3.4, 3.4, 3.4 and 3.5. As noted in previous issues of this report, Baja California and these events are located at 103 degrees from the M 7.0 in the Dodecanese Island and were probably promoted by energy concentrated at this distance from Greece. Forecast 128413 had expected today's activity was likely in early November.  In the previous issue of this summary this area had been noted because of its distance from Greece as:

 

"Lighter earthquakes today near 103 degrees from the Greek event occurred in Baja California (M 3.5) ..." (November 1, 2, 3,  2020)

 

NEIC reported the earthquake of M 3.7 in Baja California was felt with intensity II-III in the area(s) of Baja California at Bonita.

 

O:  3NOV2020 16:40:22  31.5N  115.6W ML=3.3  EMSC   BAJA CALIFORNIA, MEXICO      

O:  3NOV2020 11:04:44  31.5N  115.7W ML=2.6  EMSC   BAJA CALIFORNIA, MEXICO      

O:  3NOV2020 11:00:39  31.5N  115.7W ML=3.7  EMSC   BAJA CALIFORNIA, MEXICO      

P:  3NOV2020 128413    32.5N  115.7W 2.5-4.3 AAAAA  So. California             

P:  4NOV2020 128413    32.1N  116.4W 2.5-4.3 AAAAA  So. California             

 

STRONG EARTHQUAKE OFF THE COAST OF SOUTHERN CHILE

 

EARTHQUAKE SUMMARY FOR NOVEMBER 2, 2020

 

A strong earthquake of M 6.0 hit today in the area of southern Chile in the Aisen area. It was not reported felt in this region. This is consistent with the expectation that the western coast of South America would see strong seismicity at this time. This is the strongest earthquake within about 300 km of this epicenter since a similar M 6.0 on July 27, 2016. The last of larger magnitude in this area was an M 6.3 on May 20, 2013. Forecast 128532 had expected a strong earthquake in this region was likely around November 8. In the October 29, 2020 issue of this summary it had been noted: 

 

"An unusual earthquake of M 4.7 occurred today northwest of New Zealand. This is the strongest earthquake within about 300 km of this epicenter in at least 30 years. Earthquakes about 450 km to the southeast of this occurred on February 10, 2011 and October 7, 2001 with M 4.0-4.2. This is in an area which in the past has seen major earthquakes in South America shortly after these precursory? events. For example on February 25, 2010 this summary addressed this subject when a similar quake northwest of New Zealand occurred:

 

 

"A very unusual earthquake hit northwest of New Zealand with M 5.3 today. This is the strongest earthquake recorded within about 1000 km of this epicenter in the past 23 years. The only events in the area in recent years occurred on April

16, 1993 when earthquakes of M 4.9 and 5.0 were recorded  within about 30 of this epicenter. The epicenter has been active from time to time however. On July 26, 1987 an event of M 5.4 hit nearby. The strongest regional earthquake hit as an M 6.6 on May 20, 1960. This may be significant because one day later on May 21, 1960 one of the strongest earthquakes in modern history - an M 9+ hit Central Chile with many accompanying earthquakes of M 8+. Could this be a canary in a coal mine? Might it indicate stresses at the point of breaking elsewhere? Because there are very few events which occur in this region, no statistical statement in this regard can be made. In the four other instances of verified earthquakes near this earthquakes of M>=6.8 have hit within four days." (February 25, 2010)

 

This was followed two days later by a great earthquake in Central Chile as described in this summary as:

 

"As this report goes to press NEIC is reporting an M 8.5 in Central Chile. This is exactly what we warned about two days ago following an unusual earthquake in the ocean north of New Zealand." (February 27, 2010)

 

"A massive earthquake of M 8.8 hit off the coast of Central Chile today affecting more than two million people in Chile and Argentina. This is the strongest earthquake in the world since since the great M 9.3 earthquake in Sumatra on December 26, 2004" (February 28, 2010)" (October 29-30, 2020)

 

Today's event of M 6.0 in Chile is at the third node (120 degrees) from the  M 7.5 in Alaska Peninsula of October 19 and was probably promoted by energy from that source.

 

O:  3NOV2020 02:40:56  44.4S   79.3W Mw=6.0  EMSC   OFF COAST OF AISEN, CHILE    

P:  8NOV2020 128532    43.0S   83.0W 4.0-5.6 BBCAA  Chile Rise                 

 

The second strongest earthquake in the world today was an M 5.3 in the Ceram Sea of Indonesia. This activity was not reported in the area. It is at 103 degrees from the Dodecanese Islands of October 30 (M 7.0) - the only event in the past year of larger magnitude in the Ceram Sea was an M 5.6 on February 15, 2020. Forecast 128337 had expected activity in this area around November 6.

 

O: 03NOV2020 00:50:46   3.3S  131.1E ML=4.2  EMSC   CERAM SEA, INDONESIA

O: 02NOV2020 18:01:58   3.5S  131.1E Mw=5.3  EMSC   CERAM SEA, INDONESIA

O:  2NOV2020 20:21:54   3.3S  131.1E ML=4.4  EMSC   CERAM SEA, INDONESIA         

P:  6NOV2020 128337     6.0S  131.0E 4.0-5.3 BCAAA  West Irian, PNG            

P:  9NOV2020 128337     3.0S  134.0E 4.0-5.3 CACAA  West Irian, PNG            

 

A moderate M 4.6 was also felt along the west coast of South Island, New Zealand today. GEONET reported this earthquake was felt with strong intensity in the area of NE of Mount Cook, New Zealand and northern South Island by 457 people. 272 reports of weak, 166 of  light intensity, 16 of moderate intensity and 3 of strong shaking  came from the area near Mount Cook, New Zealand. NEIC reported this earthquake of M 3.9 in South Island, New Zealand  was felt with intensity II-III in the area(s) of  South Island, New Zealand at Hokitika and Greymouth on the west coast. Forecast 128542 and 128303 had expected this event was likely around October 6. This epicenter is at 101 degrees from the Alaska Peninsula quake of October 19 and was probably promoted by energy from that event.

 

O:  2NOV2020 09:10:38  43.2S  170.9E ML=3.9  EMSC   SOUTH ISLAND OF NEW ZEALAND  

O:  2NOV2020 09:10:39  43.2S  170.8E MS=4.6  GEONET Felt with strong intensity

P:  6NOV2020 128542    43.0S  171.0E 3.0-4.9 BAAAA  So. Island, N.Z.           

P: 25OCT2020 128303    43.0S  171.0E 3.0-4.9 CAAAA  So. Island, N.Z.           

 

 

Moderate aftershocks in the region of the Alaska Peninsula did not occur today.

The only light earthquakes in the area of M>=3 were an M 3.4 and 3.1 to the west of the aftershock zone. Forecast 128467 had expected today's activity in the area was likely around November 2.

 

O: 02NOV2020 14:34:36  53.7N  160.0W ml=3.4  EMSC   SOUTH OF ALASKA

O:  3NOV2020 02:07:06  53.4N  160.0W ml=3.1  EMSC   SOUTH OF ALASKA              

P:  2NOV2020 128467    54.8N  159.7W 3.5-4.8 ABAAA  Alaska Peninsula           

 

The earthquake swarm in Baja California which began yesterday continued today with the strongest events of M 3.5, 3.5 and 3.6. In the previous issue of this summary this swarm was noted as:

 

"A series of light earthquakes shook the region of Baja California today. This swarm included earthquakes of M 3.4, 3.4, 3.4 and 3.5. As noted in previous issues of this report, Baja California and these events are located at 103 degrees from the M 7.0 in the Dodecanese Island and were probably promoted by energy concentrated at this distance from Greece. Forecast 128413 had expected today's activity was likely in early November.  In the previous issue of this summary this area had been noted because of its distance from Greece as:

 

"Lighter earthquakes today near 103 degrees from the Greek event occurred in Baja California (M 3.5) ..." (November 1, 2,  2020)

 

O: 02NOV2020 08:22:15  31.5N  115.6W ML=3.5  EMSC   BAJA CALIFORNIA, MEXICO

O: 02NOV2020 10:56:11  31.5N  115.6W ML=3.6  EMSC   BAJA CALIFORNIA, MEXICO

O: 02NOV2020 11:09:40  31.5N  115.7W ML=2.8  EMSC   BAJA CALIFORNIA, MEXICO

O: 02NOV2020 09:00:42  31.6N  115.8W ML=2.3  EMSC   BAJA CALIFORNIA, MEXICO

O:  2NOV2020 08:11:10  31.5N  115.6W ML=3.5  EMSC   BAJA CALIFORNIA, MEXICO      

P:  4NOV2020 128413    32.1N  116.4W 2.5-4.3 AAAAA  So. California             

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in Hawaii.

NEIC reported this earthquake of M 3.5 in Hawaii  was felt with intensity II-III in the area(s) of  Hawaii at Pahala, Naalehu, Volcano, Pahoa, Mountain View, Hilo, Kurtistown, Keaau, Papakou and Pepeek3o. This is the strongest earthquake in Hawaii since an M 4.2 on August 1, 2020 and prior to that an M 4.7 on July 27, 2020. Forecast 128347 had expected today's event was likely within about 25 km of this epicenter in early November.

 

O:  2NOV2020 11:47:52  19.3N  155.4W ML=4.1  EMSC   ISLAND OF HAWAII, HAWAII     

P:  6NOV2020 128347    19.2N  155.2W 3.0-4.3 BAAAA  Hawaii                     

 

DODECANESE ISLANDS SEISMICITY EXPANDS

 

EARTHQUAKE SUMMARY FOR NOVEMBER 1, 2020

 

Enhanced seismicity began to be observed today in eastern Europe outside the aftershock zone of the Dodecanese Islands, Greece. The largest of these were an M 4.8 in northern Greece and an M 4.6 in Croatia. The event in Greece was felt with intensity IV in Megalopoli, Arkadia, Greece with intensity IV. This is the strongest earthquake within about 150 km of this epicenter since an M 5.2 on February 6, 2020. An M 5.2 hit about 200 km southwest of this on October 21, 2020. Forecast 128185 had expected today's event in this area was likely around October 28.

 

O:  1NOV2020 23:09:33  38.9N   21.6E mb=4.7  EMSC   GREECE                       

P: 28OCT2020 128185    38.0N   21.0E 3.0-4.4 BAAAA  No. Greece                 

 

The M 4.6 in Croatia was reported by NEIC to have been felt with intensity IV in Zadar and III in Policnik, Croatia. The last earthquake of M>=4.6 within about 100 km of this epicenter in Croatia was an M 4.8 on July 30, 2013. A series occurred about 200 km to the northeast of this occurred on March 22, 2020 beginning with an M 5.4. An earthquake, the largest in the past seven years of M 5.4 also occurred in the region on November 26, 2019 about 300 km southeast of today's epicenter. Forecasts 128430 and 128209 had expected enhanced seismicity in this area was likely in late October or early November.

 

O:  1NOV2020 13:15:42  44.4N   15.5E ML=4.6  EMSC   CROATIA                      

P:  2NOV2020 128430    43.0N   18.0E 3.0-4.9 ABBAA  Adriatic Sea               

P: 30OCT2020 128209    43.0N   18.0E 3.0-4.9 ABBAA  Adriatic Sea               

P:  4NOV2020 128430    45.0N   18.0E 3.0-4.9 BABAA  Adriatic Sea               

 

Moderate earthquakes also continued in the Dodecanese Islands, Greece and in Western Turkey today. These included an M 4.4 in the Dodecanese Islands and an M 4.4 in Western Turkey. These were reported to have been felt with moderate intensity in the area by EMSC. These are aftershocks of the M 7.0 in the Dodecanese Islands of October 30, 2020.

 

O: 01NOV2020 07:33:07  37.8N   26.9E ML=4.2  EMSC   DODECANESE ISLANDS, GREECE

O: 01NOV2020 12:57:02  37.8N   26.8E mb=4.4  EMSC   DODECANESE ISLANDS, GREECE

O:  1NOV2020 07:05:13  37.8N   27.0E ML=4.4  EMSC   WESTERN TURKEY               

P:  2NOV2020 128381    37.0N   27.0E 3.0-4.3 AAAAA  Aegean Sea                 

 

An unusual earthquake of  M 4.6 off northwestern Alaska occurred today in the Bering Sea. NEIC reported it was felt with intensity IV in Wales, Alaska.

The last earthquake within about 300 km of this event in the Bering Strait with M>=4.3

was an M 4.6 on November 16, 2018, the last of larger magnitude in the area was an M 5.0 on January 16, 2018.

 

O:  1NOV2020 11:44:43  65.4N  168.6W mb=4.3  EMSC   BERING STRAIT                

O:  1NOV2020 11:44:42  65.4N  168.6W mb=4.6  ANSS   BERING STRAIT                

 

Moderate earthquakes continued in the Alaska Peninsula area today. The largest of these were reported felt with intensity III in King Cove, and Chignik, Alaska and was of M 4.9. These are aftershocks of the M 7.5 of October 19. Forecasts 128467 and 128237 had expected today's activity was likely around October 31 to November 2.

 

O: 02NOV2020 03:56:09  55.1N  160.4W mb=4.9  EMSC   ALASKA PENINSULA

O: 01NOV2020 22:41:55  55.8N  158.1W Mw=4.4  EMSC   ALASKA PENINSULA

O:  1NOV2020 22:39:26  54.5N  159.7W ml=4.1  EMSC   SOUTH OF ALASKA              

P:  2NOV2020 128467    54.8N  159.7W 3.5-4.8 AAAAA  Alaska Peninsula           

P: 31OCT2020 128237    54.8N  158.7W 3.5-4.9 AAAAA  Alaska Peninsula           

 

A series of light earthquakes shook the region of Baja California today. This swarm included earthquakes of M 3.4, 3.4, 3.4 and 3.5. As noted in previous issues of this report, Baja California and these events are located at 103 degrees from the M 7.0 in the Dodecanese Island and were probably promoted by energy concentrated at this distance from Greece. Forecast 128413 had expected today's activity was likely in early November.  In the previous issue of this summary this area had been noted because of its distance from Greece as:

 

"Lighter earthquakes today near 103 degrees from the Greek event occurred in Baja California (M 3.5) ..." (November 1, 2020)

 

O: 01NOV2020 08:47:06  31.5N  115.4W ML=3.5  EMSC   BAJA CALIFORNIA, MEXICO

O: 01NOV2020 18:59:11  31.5N  115.6W ML=3.4  EMSC   BAJA CALIFORNIA, MEXICO

O: 01NOV2020 21:20:29  31.5N  115.5W ML=3.4  EMSC   BAJA CALIFORNIA, MEXICO

O: 02NOV2020 03:14:52  31.5N  115.7W ML=2.3  EMSC   BAJA CALIFORNIA, MEXICO

O:  1NOV2020 08:13:14  31.5N  115.6W ML=3.4  EMSC   BAJA CALIFORNIA, MEXICO      

P:  4NOV2020 128413    32.1N  116.4W 2.5-4.3 BAAAA  So. California             

P: 31OCT2020 128194    30.2N  114.1W 2.0-3.9 ABBAA  SW U.S.A                   

 

STRONG QUAKES IN INDONESIA; COSTA RICA; OTHERS NEAR 103 DEGREES FROM GREECE

 

EARTHQUAKE SUMMARY FOR OCTOBER 31, 2020

 

The strongest earthquake in the world today was an M 5.7-6.3 in the Banda Sea, Indonesia. It was reported felt with intensity II-III in Northern Territory, Australia at Conawarra, Palmerston, Darwin, Humpty Doo-MacMinns Lagoon and Katherine. BMG gave this event M 6.3 and reported it was felt with intensity II-II in Saumlaki and II in Dobo, Indonesia This event is at 104 degrees from the M 7.0 in the Dodecanese Islands of Greece which occurred yesterday and was probably promoted by concentrated energy from that source. Large follow-up earthquakes often occur at this distance from major surficial events as energy from them is concentrated at the surface after reflections and refractions off internal earth boundaries. This was emphasized in the previous issue as:

 

 

"Areas of Southern and Central California, eastern Mexico and Guatemala and northern South America and Indonesia area near 103 degrees from the M 7.0 epicenter and could see enhanced seismicity due to energy concentration in those areas." (October 31, 2020)

 

Other areas near 103 degrees from the Dodecanese Islands which saw moderate earthquakes today included Baja California, Chiapas, Oaxaca, Veracruz, Mexico, Costa Rica, Peru, Chile, the South Sandwich Islands among others.

 

This earthquake occurred within about 15 minutes of local solar noon and was probably triggered by high tidal stresses with the full moon which arrived today with maximum stresses while this area was sub-solar as reported in previous issues of this summary:

 

 

"The full moon will arrive on October 31 at 14:49 UT. Longitudes which are sub-solar at this time are near 40 West and 140 East. These include the central Atlantic in the west and Japan and much of the eastern Pacific Rim from Kamchatka to New Guinea in the east. These areas may see moderate seismic enhancement over the next seven days to enhanced tidal stresses but other tidally stressed areas may also see increased seismicity at this time." (October 28-31, 2020)

 

An earthquake of M 6.9 occurred on May 6, 2020 and M 7.3 on June 24, 2019 in this area. Forecast 128107 had expected today's event within about 25 km of the epicenter was likely around October 31.

 

O:  1NOV2020 03:43:20   7.1S  129.2E Mw=6.3  BMG    BANDA SEA, INDONESIA         

O:  1NOV2020 03:43:20   7.1S  129.2E Mw=5.7  EMSC   BANDA SEA, INDONESIA         

P: 31OCT2020 128107     7.0S  129.0E 4.0-5.3 AAAAA  Banda Sea                  

 

The second largest event in the world today was an earthquake of M 5.2 which shook the region of Costa Rica today. NEIC reported it was felt with maximum intensity V in Costa Rica at Angeles and Asuncion Heredia; IV in San Pablo, Sabanilla and Granadilla, San Jose and III in Llorente, Calle Blancos, Guadalupe, San Antonio and Concepcion, Costa Rica. This epicenter, like the M 6.3 in the Banda Sea is located at 100 degrees from the Dodecanese Islands, and was included in the far-field forecast (see above) from Greece. The last earthquake in Costa Rica with M>5.2 was an M 6.0 on August 4, 2020 and prior to that an M 6.5 on November 13, 2017. The passage of Hurricane Zeta earlier this week may have help abet today's event as noted at the time:

 

 

"Hurricane Zeta formed today over Northern Yucatan with winds up to 65 kts. It is expected to track to the northeast as a Hurricane October 27-30 and to make landfall near New Orleans, Louisiana around October 28-29 as a hurricane. Unloading atmospheric pressures under the eye could lift the area of eastern Mexico promoting elevated seismicity to the south in Chiapas, Oaxaca, Mexico and in Costa Rica north to Guatemala over the next several days." (October 27-28, 2020)

 

Forecasts 128120 and 128098 had expected today's activity in Costa Rica within  about 50 km of this epicenter was likely at the end of October.

 

O:  1NOV2020 05:01:11  10.0N   84.3W mb=5.1  EMSC   COSTA RICA                   

O:  1NOV2020 05:01:11  10.0N   84.3W mb=5.2  ANSS   COSTA RICA                   

P: 23OCT2020 128120    10.0N   84.0W 3.5-5.0 CAAAA  Caribbean Sea              

P: 26OCT2020 128098     9.0N   84.0W 3.5-4.9 BAAAA  Costa Rica                 

 

The third largest earthquake in the world today - an M 5.1 in the South Sandwich Islands was also located at 104 degrees from the Dodecanese Islands. Forecast 128308 had expected this activity was likely about 100 km south of today's epicenter around October 29. Lighter earthquakes today near 103 degrees from the Greek event occurred in Baja California (M 3.5), Northern Peru (M 4.0), Oaxaca, Chiapas and Veracruz, Mexico.

 

O: 31OCT2020 21:04:06  55.8S   27.1W mb=5.1  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 29OCT2020 128308    57.0S   27.0W 4.0-5.6 ABAAA  So. Sandwich Islands       

 

Moderate aftershocks continued to be felt today in the region of the Dodecanese Islands. NEIC reported these were felt with moderate intensity in Samos, Greece and in western Turkey. Updated tolls from the area included 2 dead in Greece, 51 in Turkey and a total of 915 injuries. Buildings also collapsed in Turkey in Izmir, Bayrakli and Bornova districts. Relief efforts concentrated in the areas where buildings collapsed. Forecasts 128230 and 128163 had expected this activity at the end of October.

 

O: 31OCT2020 08:41:51  37.9N   26.9E ML=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 12:37:03  37.9N   26.6E ML=4.0  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 14:42:42  37.9N   26.5E ML=4.2  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 14:42:42  37.9N   26.5E mb=4.5  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 16:06:13  37.9N   26.7E ML=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 22:05:43  37.9N   26.9E mb=4.0  EMSC   DODECANESE ISLANDS, GREECE

O:  1NOV2020 05:27:05  37.8N   26.9E ML=4.0  EMSC   DODECANESE ISLANDS, GREECE   

O:  1NOV2020 05:27:05  37.8N   26.9E ML=4.0  EMSC   DODECANESE ISLANDS, GREECE   

P: 26OCT2020 128163    35.0N   25.0E 3.0-4.3 BCBAA  Aegean Sea                 

P: 30OCT2020 128230    41.0N   27.0E 3.0-4.8 ACAAA  Romania/NW Turkey           

 

 

 

An M 2.6 earthquake occurred today in Alabama. It was not reported felt in the area. The last earthquake with M>=2.6 in Alabama within about 150 km of this epicenter occurred on June 27, 2020 with M 2.7. Hurricane Zeta passed over this epicenter yesterday, and stresses from this storm probably helped promoted today's event as noted in previous issues of this report:

 

"Hurricane Zeta continued today over the southeastern U.S. with winds up to 60 kts. It is expected to track to the northeast after making landfall in the region of Louisiana today. Some regional seismicity in the Southeast U.S. may be enhanced while this storm dissipates over the area." (October 29-30, 2020)

 

Forecast 128203 had expected today's event in Alabama was likely in late October.

 

O:  1NOV2020 02:28:22  34.5N   86.6W ML=2.6  EMSC   ALABAMA                      

P: 24OCT2020 128203    34.0N   85.0W 2.0-3.8 CAAAA  Southeast U.S.             

 

MAJOR M 7.0 QUAKE AND TSUNAMI DAMAGING, DEADLY IN GREECE AND TURKEY

 

EARTHQUAKE SUMMARY FOR OCTOBER 30, 2020

 

A major earthquake occurred in the Dodecanese Islands of Greece west of Turkey today with M 7.0. A moderate tsunami reportedly slammed into coastal areas of Turkey and islands of Greece according to local news sources. The tsunami deluged the city of Izmir, Turkey with surging seawater which inundated the city with debris and caused a major recession of the water revealing ocean bottom. Other areas visited by the tsunami included the Greek islands of Ikaria, Kos, Samos and Seferihisar. Tsunami warnings were issued for the area. At least 20 buildings collapsed in Izmit, Turkey and the Dodecanese Islands and 20 were initially reported killed by the quake and one was drowned by the tsunami, but these tolls are expected to rise. Among the destroyed buildings was the Church of the Virgin Mary in Karlovasi. Two others were killed on Samos Island, Greece. At least 790 people were reported injured in the quake and tsunami. The tsunami caused many to flee inland. Relief operations are in effect by a series of Mediterranean countries including Israel, Azerbaijan, France, Turkey and Greece, NATO and the European Union. This is the first earthquake in the region of Greece which caused such extensive damage and deaths since an M 6.6 in the Aegean Sea in July 21, 2017. This follows an electric shock from the sun several hours earlier. It also coincides with planetary alignments with the sun, earth and Uranus and with Mars, Earth and Venus which are perpendicular to each other. But the main tidal stresses leading to the promotion of this earthquake are probably those associated with the full moon which arrives today as noted in previous issues of this summary as:

 

"The full moon will arrive on October 31 at 14:49 UT. Longitudes which are sub-solar at this time are near 40 West and 140 East. These include the central Atlantic in the west and Japan and much of the eastern Pacific Rim from Kamchatka to New Guinea in the east. These areas may see moderate seismic enhancement over the next seven days to enhanced tidal stresses but other tidally stressed areas may also see increased seismicity at this time."  (October 30, 2020)

 

The mainshock in Greece occurred within about an hour of local solar noon, a time when tidal stresses are maximized.

 

and with the continuing geomagnetic storm as:

 

"This is the strongest disturbance in the  geomagnetic field since September 28.  Strong disturbances in the geomagnetic field can help promote seismicity and may do so at high and low latitudes with this storm." (October 25-29, 2020)

 

The strongest solar flare since May 29, 2020, four months ago,  occurred almost exactly one day earlier as an C4.3 on October 29, 2020 beginning at 11:30 UT and may have affected the timing of today's Dodecanese mainshock.

 

The earthquakes in the area of M 6.3 on June 12, 2017 and of M 6.6 on July 20, 2017 were also associated with tidal alignments as noted at the time in this summary:

 

 

"A strong earthquake near the Greece-Turkey border occurred today with M 6.3.

The mainshock caused considerable damage in Plomarion, Lesvos, Greece where it was felt with intensity IX. Intensity VI was also felt in Tire, Mimarsinan, Istanbul, Dikili, Izmir, Turkey, and VII in Canakkale, Turkey more than 125 km from the epicenter. Intensity V was also felt in Turkey at Ayvalik, Cesme, Menemen, Aftershocks up to M 4.4 were reported felt with intensity II-III in Greece at Skoutaros and in Turkey at Izmir. Intensity V was felt within about 100 km of the epicenter; IV within about 150 km and II-III as far as 500 km away in Sofia, Bulgaria. As noted in previous issues of this summary tidal stresses apparently set this region up for this seismicity:

 

 

"Seismicity associated with high stresses related to the full moon of June 9 continued today in Turkey and eastern Europe. Turkey is especially prone to such influences as was noted when a great earthquake, the Izmit quake, of August, 1999 devastated much of the area. That quake occurred several days after the total solar eclipse was visible over the epicentral area, probably illustrating the role of tidal triggering in that event." (June 11-12, 2017)

 

"The full moon will arrive on June 9 at 21:43 UT. Longitudinal zones which are sub-solar at this time are near 145 West  longitude while those at anti-solar locations are near 35 East longitude. These include seismic areas of eastern Europe and the mid-east while those in the west are concentrated in east and central Alaska, Hawaii and the west coast of the U.S. While tidal triggering can occur in many areas including outside these zones, tidal stresses are highest in these areas and seismicity is likely to be elevated from about June 7 and June 12, 2017." (June 7-12, 2017) (June 13, 2017)

 

 

"A strong earthquake of M 6.7 hit the Greek Dodecanese Islands today. This was a tidally promoted event as it occurred within about 15 minutes of local solar midnight in an area where high tidal stresses and triggering were expected at this time as noted in the previous issue of this report" (July 21, 2017)

 

The event of M 6.6 on July 20, 2017 was also accompanied by a strong geomagnetic storm as noted at the time in this summary:

 

"Geomagnetic effects from the strongest high latitude geomagnetic storm in more than a year were also prominent earthquake promoters at this time" (July 21, 2017)

 

In the previous issue of this summary, the activation of the region of eastern Europe had been noted as:

 

 

"Areas of eastern Europe have seen elevated seismicity in the past several days, possibly related to the geomagnetic storm. Earthquakes of moderate size have shook Turkey and Switzerland in this time." (October 29-30, 2020)

 

Today's activity in the Dodecanese Islands is at the fourth node (90 degrees) from the Alaska Peninsula event of M 7.5 of October 19 and may have been promoted by energy from that source. NEIC reported today's mainshock of M 7.0 was felt with maximum intensity in Samos, Greece with VII; VI in Izmir and Aydin, Turkey V in Neon Kariovasion and Ayios Greece  and IV in Marathokambos, Samos, Greece. An aftershock of M 5.2 as also reported felt in Turkey with maximum intensity VI at Torbali, Izmir and V in Izmir with III in Koridallos, Attiki, Greece. It is located at the fourth node (90 degrees) from the Alaska Peninsula in an area where triggering from that event was considered likely in the far-field forecast of October 19 as:

 

"90 degrees (node 4): Alaska Peninsula to ... Crete, Lebanon ... " (October 19-20, 2020)

 

This epicenter is also at 104 degrees from the M 7.5 in Oaxaca, Mexico of June 23, 2020 as were events today in the Solomon Islands of M 5.5 and in Japan of M 3.7. These were probably promoted by concentrated energy from these sources.

 

Areas of Southern and Central California, eastern Mexico and Guatemala and northern South America and Indonesia area near 103 degrees from the M 7.0 epicenter and could see enhanced seismicity due to energy concentration in those areas.

 

The last earthquake within about 250 km of the M 7.0 today in the Dodecanese Islands with M>=7 occurred on December 19, 1981 with M 7.6 and prior to that on March 28, 1970 with M 7.3. The strongly damaging quake and tsunami in Izmit, Turkey on August 17, 1999 and an M 7.3 to the east of that on November 12, 1999 were the last within about 500 km at this magnitude level. The event on August 17, 1999 was associated with a major solar eclipse which occurred over the epicenter several days earlier.  Forecasts 128163, 128205 and 128230 had expected regional enhanced seismicity in the area of northwestern Turkey at the end of October.

 

O: 30OCT2020 12:01:37  37.8N   27.0E ML=4.4  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 12:33:20  37.8N   26.8E ML=4.1  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 15:06:46  37.8N   26.8E ML=4.0  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 15:14:56  37.8N   26.8E mb=5.2  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 15:19:17  37.8N   26.9E ML=4.6  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 19:08:55  37.8N   26.3E mb=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 21:46:24  37.8N   26.8E ML=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 23:05:29  37.8N   26.9E ML=4.1  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 23:19:10  37.8N   26.4E ML=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 00:20:51  37.8N   27.0E ML=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 01:40:31  37.8N   26.4E mb=4.0  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 02:10:17  37.8N   25.9E ML=4.0  EMSC   DODECANESE ISLANDS, GREECE

O: 31OCT2020 05:31:29  37.8N   26.8E Mw=4.8  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 11:51:25  37.9N   26.8E Mw=7.0  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 11:53:54  37.9N   26.8E ML=4.6  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 11:58:05  37.9N   26.9E ML=4.3  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 12:04:43  37.9N   26.3E ML=4.3  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 12:19:10  37.9N   26.7E ML=4.1  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 12:29:50  37.9N   27.0E ML=4.2  EMSC   WESTERN TURKEY

O: 30OCT2020 13:00:44  37.9N   26.9E ML=4.9  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 13:06:57  37.9N   27.0E ML=4.2  EMSC   WESTERN TURKEY

O: 30OCT2020 14:46:10  37.9N   26.7E ML=4.2  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 15:24:34  37.9N   26.9E ML=4.0  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 16:40:17  37.9N   27.0E ML=3.9  EMSC   DODECANESE ISLANDS, GREECE

O: 30OCT2020 17:16:04  37.9N   27.0E mb=4.3  EMSC   WESTERN TURKEY

O: 30OCT2020 11:55:02  38.0N   27.0E ML=3.9  EMSC   WESTERN TURKEY

O: 30OCT2020 11:59:29  37.8N   27.0E ML=4.1  EMSC   WESTERN TURKEY               

P: 25OCT2020 128163    38.0N   23.0E 3.0-4.3 BACAA  Aegean Sea                 

P: 30OCT2020 128205    39.0N   33.0E 3.5-5.1 ABCAA  Turkey                     

P: 30OCT2020 128230    41.0N   27.0E 3.0-4.8 ACAAA  Romania/NW Turkey          

 

An earthquake of M 5.6 in the Solomon Islands preceded the M 7.0 in the Dodecanese Islands today. This event was reported felt with intensity IV in Honiara, Guadalcanal, Solomon Islands. This epicenter is at the fifth node (72 degrees) from the M 7.5 in the Alaska Peninsula of October 19 and may have been promoted by energy from that source. SS phases from the Solomon Islands would have been present in the Dodecanese Islands when that subsequent quake occurred and may have helped trigger it. This event occurred near local solar midnight and may have been promoted by high tidal stresses with the full moon which are maximized near this time. This is the strongest quake within about 200 km of this epicenter since an M 5.8 about 150 km to the south on July 18, 2020. Forecast 128273 had expected today's event within about 150 km of this  epicenter was likely in late October.

 

O: 30OCT2020 11:10:14   8.9S  161.0E Mw=5.6  EMSC   SOLOMON ISLANDS              

P: 25OCT2020 128273    10.0S  162.0E 4.0-5.3 BBAAA  No. of Santa Cruz Islands  

 

The earthquake in the Dodecanese Islands today followed an M 5.9 in the northern Mid-Atlantic Ridge by about three hours.  The Atlantic earthquake occurred near the longitude of maximum tidal stress (40 vs 43 West longitude- see above) and was probably promoted by high tidal stresses associated with the full moon. 

 

Today's activity in the mid-Atlantic  is at 105 degrees from the Alaska Peninsula event of M 7.5 of October 19 and may have been promoted by energy from that source. Energy from strong earthquakes on the surface concentrates at this distance due to reflections and refractions off internal earth boundaries and can help trigger additional seismicity at this distance.

 

This is the strongest earthquake in the northern Mid-Atlantic within about 200 km of this epicenter since an M 6.6 on June 24, 2013 and prior to that an M 5.9 on July 27, 2011.

 

O: 30OCT2020 08:38:41  10.6N   43.5W Mw=5.9  EMSC   NORTHERN MID-ATLANTIC RIDGE  

 

 

This summary also expected a strong quake at this time on the western rim of

South America. A moderate earthquake of M 5.5 hit the region of northern Peru today. NEIC reported it was felt with maximum intensity V in Oxapampa, Pasco, Peru and IV in Huanuco and II-III in Pucallpa, Nicolas de Pierola and Santa Maria Lima, Peru. This event also occurred within about an hour of local solar noon and was likely promoted by high tidal stresses. This epicenter is also at 104-105 degrees from the Dodecanese Islands earthquake of M 7.0 today and was likely promoted by concentrated energy from that source. Other such earthquakes today occurred  at this distance in Indonesia and Oaxaca/Chiapas, Mexico. This earthquake is the strongest within about 200 km of this epicenter since an M 5.7 exactly three years ago on October 30, 2017.  Forecast 128270 had expected today's activity to the south of this epicenter.

 

 

 

O: 30OCT2020 18:24:41  10.3S   75.3W Mw=5.5  EMSC   CENTRAL PERU                  

P: 30OCT2020 128270    14.0S   76.0W 4.0-5.4 ACAAA  Central Peru               

 

Elsewhere a series of moderate earthquakes hit the Jan Mayen region of the Arctic Ocean. The strongest of these was an M 5.6 with a foreshock of M 4.6 and an aftershock of M 5.3. They occurred within about an hour of local solar midnight and were also probably promoted by strong tidal stresses.

 

Today's activity in the Jan Mayen area is at the seventh node (52 degrees) from the Alaska Peninsula event of M 7.5 of October 19 and may have been promoted by energy from that source. While an M 4.4 at this epicenter occurred on October 19, 2020, the last of M>=5.6 in the area was an M 5.6 to the northeast on November 28, 2017. The last of larger magnitude was an M 6.2 on January 29, 2011, the largest within about 300 km in the past 30 years. Forecast 128266 had expected today's activity in this region was likely around October 31 within about 50 km of today's events. This activity is near the 10th node (36 degrees) from the Dodecanese M 7.0 today and may have been enhanced by energy from  that source.

 

O: 30OCT2020 22:56:47  71.6N    3.3W Mw=5.6  EMSC   JAN MAYEN ISLAND REGION

O: 30OCT2020 23:46:45  71.6N    3.4W Mw=5.3  EMSC   JAN MAYEN ISLAND REGION

O: 31OCT2020 03:54:32  71.6N    4.5W ML=4.2  EMSC   JAN MAYEN ISLAND REGION

O: 30OCT2020 22:44:10  71.5N    3.3W mb=4.6  EMSC   JAN MAYEN ISLAND REGION      

P: 31OCT2020 128266    72.0N    0.0E 3.0-4.3 AAAAA  Norway                     

 

A moderate swarm occurred in southern Idaho today. The strongest of these was an M 3.6 which occurred at 12:15 U.T. twenty-four minutes after the M 7.0 in the Dodecanese Islands. It is located at the fourth node (90 degrees) from that event. S-phases from Turkey would have been at this epicenter when the M 3.6 occurred and may have helped trigger it at this time. The last event of M>3.6 in the aftershock zone of the March 31, 2020 M 6.5 in southern Idaho was an M 4.4 on September 8, 2020. Forecast 128220 had expected today's activity was likely in this area around October 25-28.

 

NEIC reported the earthquake of M 3.3-3.6 in Southern Idaho was felt with intensity II-III in the area(s) of Southern Idaho at Meridian.

 

O: 30OCT2020 07:28:38  44.3N  115.1W ML=2.6  EMSC   SOUTHERN IDAHO

O: 30OCT2020 07:28:38  44.3N  115.1W ML=2.6  EMSC   SOUTHERN IDAHO

O: 30OCT2020 11:54:57  44.3N  115.1W Ml=2.7  EMSC   SOUTHERN IDAHO

O: 30OCT2020 12:15:30  44.3N  115.1W Ml=3.6  EMSC   SOUTHERN IDAHO

O: 30OCT2020 13:07:18  44.3N  115.0W Ml=2.3  EMSC   SOUTHERN IDAHO

O: 30OCT2020 21:26:23  44.3N  115.1W Ml=2.1  EMSC   SOUTHERN IDAHO

O: 30OCT2020 16:23:33  44.4N  115.2W Ml=2.2  EMSC   SOUTHERN IDAHO

O: 30OCT2020 20:18:49  44.4N  115.2W Ml=2.9  EMSC   SOUTHERN IDAHO

O: 30OCT2020 20:46:17  44.1N  115.1W Ml=3.3  EMSC   SOUTHERN IDAHO               

P: 25OCT2020 128220    44.5N  115.2W 2.0-3.9 BAAAA  Montana/Idaho              

P: 28OCT2020 128220    44.6N  116.0W 2.0-3.9 AAAAA  Montana/Idaho              

 

An event of M 4.7 in the Alaska Peninsula was the strongest in the U.S. or Canada today. The strongest earthquake in the U.S. or Canada today outside the Alaska Peninsula was an M 3.6 in southern Quebec, Canada. It was not reported felt in Southern Quebec. Forecast 128227 had expected regional activity in late October. This is an unusual earthquake - the largest within about 150 km of this epicenter in the past 30 years The epicenter is located at the fifth node (72 degrees) from the Dodecanese quake of M 7.0 today and was probably promoted by energy from that source.

 

O: 30OCT2020 18:28:42  48.4N   78.5W mb=3.6  EMSC   SOUTHERN QUEBEC, CANADA      

P: 30OCT2020 128227    46.0N   81.0W 2.0-3.9 ACBAA  Ohio/Lake Erie             

 

GLOBAL SEISMICITY GOES QUIET - UH OH

 

EARTHQUAKE SUMMARY FOR OCTOBER 29, 2020

 

Global seismicity today was at extremely quiet levels. The strongest earthquakes

were of M 5.1 in the Alaska Peninsula; M 5.3 in Tonga and M 4.9 in the Samar, Philippines and southern Peru. As this occurs during a strong, continuing geomagnetic storm and at the full moon, it is likely the calm before the storm with a number of moderately strong to strong earthquakes likely in the next several days. While this summary, in previous issues, has identified several regions where this might occur (such as the coast of South America), the full moon tidal forecast and geomagnetic seismicity forecast have provided a more concise and general view as:

 

 

"The full moon will arrive on October 31 at 14:49 UT. Longitudes which are sub-solar at this time are near 40 West and 140 East. These include the central Atlantic in the west and Japan and much of the eastern Pacific Rim from Kamchatka to New Guinea in the east. These areas may see moderate seismic enhancement over the next seven days to enhanced tidal stresses but other tidally stressed areas may also see increased seismicity at this time."  (October 30, 2020)

 

 

"This is the strongest disturbance in the  geomagnetic field since September 28.  Strong disturbances in the geomagnetic field can help promote seismicity and may do so at high and low latitudes with this storm." (October 25-29, 2020)

 

The earthquake in Tonga/Fiji today of M 5.3, the strongest in the world today was not reported felt. It joined four other moderate quakes in the region today. Forecast 128292 had expected today's event within about 50 km was likely around October 28.

 

O: 30OCT2020 02:34:23  20.7S  178.6W Mw=5.3  EMSC   FIJI REGION                  

P: 28OCT2020 128292    21.0S  179.0W 4.0-5.3 AAAAA  Tonga Islands              

 

Several moderate earthquakes occurred today in the Mindoro, Philippines area today. NEIC reported this earthquake of M 4.8 in Mindoro, Philippines was felt with intensity II-III in the area(s) of Mindoro, Philippines in Southern Tagalog at Cnenca and Indang (IV) and Calantas, Mahabang, Luksuhin, Tagayhlay, Malabag and Dainta. PHIVOLCS reported this quake with M 5.0 was felt with intensity IV in the Philippines in Mabini, San Luis, Lemery, Rosario, Agoncillo, Calatagan, Balayan, Bauan, Sta. Teresita, Batangas; Tagaytay City, Alfonso and Amadeo, Cavite; III in Batangas City; Malvar, Talisay, Tanauan, Alitagtag Batangas; San Pablo, Luguna; II in Quezon City; Mandaluyong City, Navotas City, Majayjay, Laguna, Dolores, Quezon and I in Malabon City; Pasay City; Sta. Cruz, Laguna.

NEIC reported the aftershock of M 4.6 in Samar, Philippines  was felt with intensity II-III in the area(s) of  Samar, Philippines in Cuenca (IV) and Malabag, Southern Tagalog. This earthquake may have been triggered by low atmospheric pressures associated with Typhoon Molave which passed over the epicenter two days ago as noted in this summary:

 

"Typhoon Molave (TD 21W) continued today west of Samar, Philippines winds up to 125 kts. It is expected to track to the west over the next several days reaching southeastern Asia around October 29 as a typhoon. Seismicity in Southern Asia is expected to be enhanced by stresses from this storm as it makes landfall." (October 25-27, 2020)

 

Forecast 128131 had expected today's activity was likely within about 100 km around October 25.

 

O: 29OCT2020 05:25:43  13.8N  120.9E mb=4.8  EMSC   MINDORO, PHILIPPINES         

O: 29OCT2020 07:23:07  13.7N  121.0E mb=4.6  EMSC   MINDORO, PHILIPPINES          

P: 28OCT2020 128131    12.0N  121.0E 3.5-4.8 ABAAA  Luzon, Philippines         

 

 

One of the areas where seismicity was expected to increase with the current full moon was the coast of South America. The strongest quake in this region today was an M 4.9 in Southern Peru and northern Chile. GUC reported this earthquake was felt with intensity  IV in  Arica and Parinacota at Codpa and III in Cuya, Pocon Chile and Arica, San Miguel de Azapa and II in Putre, Chile. NEIC reported this earthquake of M 4.9 in  Southern Peru was felt with intensity II-III in the area(s) of  Southern Peru in Arica, Tarapaca, Chile. The last earthquake within about 150 km of this epicenter with M>=4.9 occurred as an M 4.9 on June 2, 2020 and prior to that an M 5.1 on April 9, 2020. This epicenter is at 103 degrees from the M 7.5 in the Alaska Peninsula of October 19. It was probably promoted by concentrated energy from that source. Forecast 128278 had expected today's event was likely within about 100 km around October 28-30.

 

O: 29OCT2020 16:08     17.7S   69.9W mb=4.7  GUC    Arica and Parinacota at Codpa

O: 29OCT2020 16:08:37  17.8S   69.7W Mw=4.9  EMSC   TARAPACA, CHILE              

P: 30OCT2020 128278    18.0S   69.0W 4.0-5.4 AAAAA  So. Peru/Bolivia           

P: 28OCT2020 128278    18.0S   71.0W 4.0-5.4 AAAAA  So. Peru/Bolivia           

 

 

The strongest earthquake in the U.S. or Canada today was an M 5.1 aftershock of the M 7.5 in the area south of Alaska of October 19. It is the strongest aftershock in the area since an M 5.2 on October 20, 2020. It was probably felt lightly in the area but was not reported so. Forecast 128237 had expected today's activity within the aftershock zone was likely around October 31.

 

O: 29OCT2020 16:32:28  54.4N  159.6W Mw=4.1  EMSC   SOUTH OF ALASKA

O: 29OCT2020 12:19:40  54.6N  159.8W ML=3.6  EMSC   SOUTH OF ALASKA

O: 30OCT2020 04:36:26  54.6N  159.8W Mw=5.1  EMSC   SOUTH OF ALASKA

O: 30OCT2020 06:42:44  54.3N  159.6W ML=3.6  EMSC   SOUTH OF ALASKA              

P: 31OCT2020 128237    54.8N  158.7W 3.5-4.9 AAAAA  Alaska Peninsula           

 

An unusual M 4.4 was also felt today in the area of Romania. NEIC reported this earthquake of M 4.4 in Romania  was felt with intensity II-III in the area(s) of  Romania with IV at Tomesti, Holboca and in Iasi at Barnova, Miroslava, Iasi, Husi, Balti and Faiticeni. Areas of eastern Europe have seen elevated seismicity in the past several days, possibly related to the geomagnetic storm. Earthquakes of moderate size have shook Turkey and Switzerland in this time. The last earthquake in Romania of M>=4.4 was an M 4.9 on April 24, 2020. Forecast 128231 had expected today's event within about 100 km was likely around October 29.

 

O: 29OCT2020 22:39:36  46.8N   27.5E mb=4.4  EMSC   ROMANIA                       

P: 29OCT2020 128231    46.0N   27.0E 3.0-4.8 AAAAA  Romania/NW Turkey          

 

STRONG SEISMICITY CONTINUES ALONG WESTERN COAST OF SOUTH AMERICA

 

EARTHQUAKE SUMMARY FOR OCTOBER 28, 2020

 

Strong seismicity continued along the coast of South America today. This included moderately moderate to large quakes in the Pacific-Antarctic Ridge (M 4.7); South Sandwich Islands (M 4.9), Easter Island (M 5.3), South Shetland Islands (M 5.4), Coquimbo, Chile (M 5.8) and in central Peru (M 5.6). This had been anticipated in the previous issue of this report as:

 

"The C4.3 solar flare occurred near local solar midnight along the western coast of South America and may have helped promote an M 5.5 in Maule, Chile today. An M 5.5 in Sulawesi, Indonesia at the opposite longitude (local solar noon) may also have been promoted this solar/geomagnetic activity." (October 28, 2020)

 

The geomagnetic storm continued today and joined with high tidal stresses associated with the full moon of October 31 as noted in previous issues of this summary:

 

"The full moon will arrive on October 31 at 14:49 UT. Longitudes which are sub-solar at this time are near 40 West and 140 East. These include the central Atlantic in the west and Japan and much of the eastern Pacific Rim from Kamchatka to New Guinea in the east. These areas may see moderate seismic enhancement over the next seven days to to enhanced tidal stresses." (October 27-28, 2020)

 

An M 5.8 was widely felt in Coquimbo, Chile today. NEIC reported maximum intensity was felt with V at Coquimbo, Ovalle, Vina del Mar and Valparaiso; IV in La Serena and II-III in Quilpue, Santiago and Graneros and in Argentina at La Rioja and Mendoza. GUC reported this earthquake was felt with intensity  VI in  Atacama at Vallenar; V in Tierra Amarilla, Jiasco. Freirina. Copiapo. Alto del Carmen; IV in Conay, El Transito and III in Caldera; in Coquimbo with IV in Illapel, La Higuera, La Serena, Ovalle, V in Coquimbo, Rio Hurtado, Salamanca and Vicuna; IV in Combarbala, Mone Patria, Paiguano, Punitaqui, and in Valparaiso with IV in San Felipe, Valparaiso and III in Zapallar, Chile. This is the strongest regional aftershock to date of the M 6.8 which hit near this epicenter on September 1, 2020. The epicenter was about 150 km south of the event of September 1 and north of an M 6.3 on September 6, 2020. The last event within about 150 km of today's quake was an M 6.4 on June 14. 2019. Forecast 128285 had expected today's event was likely within  about 50 km of this epicenter around October 31.

 

O: 28OCT2020 15:39:20  29.3S   71.2W mb=4.1  EMSC   COQUIMBO, CHILE

O: 28OCT2020 14:53:08  29.3S   71.2W Mw=5.8  EMSC   COQUIMBO, CHILE              

O: 28OCT2020 14:53     29.3S   71.2W mb=5.8  GUC    Atacama at Vallenar

P: 31OCT2020 128285    29.0S   71.0W 4.0-5.3 BAAAA  Coast Central Chile        

 

An M 5.6 was also felt widely central Peru. NEIC reported intensity VI in Palpa, Ica and II in Ica at Nazca and Santiago and in Mala and Lima, Peru. This epicenter is at 99 degrees from the M 7.5 in the Alaska Peninsula quake of October 19 and was probably enhanced by energy from that source. This may be an aftershock of the M 7.7 at this epicenter which occurred on November 12, 1996. The last earthquake within about 150 km of this epicenter was an M 5.8 on May 8, 2019 about 150 km southeast of this epicenter. An M 7.1 also occurred in this area on January 14, 2018. Forecast 128270 had expected today's activity was likely around October 30.

 

O: 28OCT2020 18:47:31  14.9S   75.5W mb=4.7  EMSC   NEAR COAST OF CENTRAL PERU

O: 28OCT2020 09:02:32  14.9S   75.7W Mw=5.6  EMSC   NEAR COAST OF CENTRAL PERU   

P: 30OCT2020 128270    14.0S   76.0W 4.0-5.4 AAAAA  Central Peru               

 

An M 5.4 also occurred in the South Shetland Islands today. It followed a smaller M 4.7 three minutes earlier. The only event in this area of larger magnitude in the current series was an M 5.8 on October 2 - the strongest in the area in the past year.

 

"Seismicity in the South Shetland Islands continued unabated today. Two moderate earthquakes of M 4.8 and 4.5 were reported in the area today. The M 4.8 occurred within about 15 minutes of local solar noon and was probably  promoted by strong tidal stresses which maximize near this hour. The full moon will be arriving in three days at this time of day in the South Shetland Islands and will probably continue to promote regional seismicity ..." (October 28, 2020)

 

Note that the M 5.8 of October 2, 2020 was also associated with the full moon.

 

Forecast 128309 had expected today's activity in the South Shetland Islands was likely around October 25.

 

O: 28OCT2020 22:00:25  62.3S   58.1W Mw=5.4  EMSC   SOUTH SHETLAND ISLANDS       

O: 28OCT2020 21:57:00  62.3S   58.1W mb=4.7  EMSC   SOUTH SHETLAND ISLANDS

P: 25OCT2020 128309    61.0S   58.0W 4.0-5.4 BAAAA  So. Shetland Is.           

 

An earthquake of M 4.9 also occurred today in the South Sandwich Islands and was associated with the activation of South America. Forecast 128308 had expected this event within about 100 km of this epicenter was likely around October 24.

 

O: 29OCT2020 04:44:42  58.0S   25.3W mb=4.9  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 24OCT2020 128308    57.0S   26.0W 4.0-5.6 BAAAA  So. Sandwich Islands       

 

An unusual earthquake of M 4.7 occurred today northwest of New Zealand. This is the strongest earthquake within about 300 km of this epicenter in at least 30 years. Earthquakes about 450 km to the southeast of this occurred on February 10, 2011 and October 7, 2001 with M 4.0-4.2. This is in an area which in the past has seen major earthquakes in South America shortly after these precursory? events. For example on February 25, 2010 this summary addressed this subject when a similar quake northwest of New Zealand occurred:

 

 

"A very unusual earthquake hit northwest of New Zealand with M 5.3 today. This is the strongest earthquake recorded within about 1000 km of this epicenter in the past 23 years. The only events in the area in recent years occurred on April 16, 1993 when earthquakes of M 4.9 and 5.0 were recorded  within about  30 of this epicenter. The epicenter has been active from time to time however. On July 26, 1987 an event of M 5.4 hit nearby. The strongest regional  earthquake hit aas an M 6.6 on May 20, 1960. This may be significant because one day later on May 21, 1960 one of the strongest earthquakes in modern history - an M 9+ hit Central Chile with many accompanying earthquakes of M 8+. Could this be a canary in a coal mine? Might it indicate stresses at the point of breaking elsewhere? Because there are very few events which occur in this region, no statistical statement in this regard can be made. In the four other instances of verified earthquakes near this earthquakes of M>=6.8 have hit within four days." (February 25, 2010)

 

This was followed two days later by a great earthquake in Central Chile as described in this summary as:

 

"As this report goes to press NEIC is reporting an M 8.5 in Central Chile.

This is exactly what we warned about two days ago following an unusual earthquake in  the ocean north of New Zealand." (February 27, 2010)

 

"A massive earthquake of M 8.8 hit off the coast of Central Chile today affecting more than two million people in Chile and Argentina. This is the strongest earthquake in the world since since the great M 9.3 earthquake in Sumatra on December 26, 2004" (February 28, 2010)

 

O: 28OCT2020 14:23:38  37.8S  169.5E ML=4.7  EMSC   NORTHWEST OF NEW ZEALAND     

 

An M 5.3 also occurred in the Easter Island region off the coast of South America today. The last earthquake within about 150 km of this epicenter with M>=5.3 occurred as an M 5.9 on June 18, 2016 and prior to that an M 5.4 on April 16, 2016. Forecast 128288 had expected activity in this area around October 28.

 

O: 28OCT2020 22:08:08  29.8S  111.8W mb=5.3  EMSC   EASTER ISLAND REGION         

P: 28OCT2020 128288    25.0S  112.0W 4.0-5.3 ACAAA  So. East Pacific Rise       

 

Seismicity in the U.S. and Canada today was relatively quiet. The strongest event was an M 4.0 in the Alaska Peninsula, the quietest day in that area since the M 7.5 of October 19. A pair of light to moderate quakes in the active area of western Texas near Pecos of M 3.8 and 3.9 also occurred today. These are the strongest aftershocks to date of the M 5.0 which hit the area on March 26, 2020. Forecast 128195 had expected today's activity was likely around October 27.

 

O: 28OCT2020 14:07:37  31.7N  104.1W mb=3.9  EMSC   WESTERN TEXAS

O: 29OCT2020 01:40:06  31.7N  104.3W ML=3.8  EMSC   WESTERN TEXAS

O: 28OCT2020 07:42:44  31.0N  103.3W ML=2.6  EMSC   WESTERN TEXAS                

O: 28OCT2020 08:07:29  31.6N  104.3W ML=2.8  EMSC   WESTERN TEXAS                 

P: 27OCT2020 128195    31.6N  103.6W 2.0-3.8 AAAAA  SW U.S.A                   

 

An earthquake of M 5.8 also occurred in the region of Vanuatu today. It was not reported felt in the area. The last earthquake of M>=5.8 within about 200 km  of this epicenter in Vanuatu was an 5.9 on July 5, 2020. Forecast 128283 had expected today's event was likely within about 100 km of this epicenter around October 30.

 

O: 28OCT2020 14:12:56  14.4S  167.5E Mw=5.8  EMSC   VANUATU                      

P: 30OCT2020 128283    15.0S  168.0E 4.0-5.3 AAAAA  Vanuatu Islands            

 

Several moderate earthquakes occurred today in the Mindoro, Philippines area today. NEIC reported this earthquake of M 4.8 in Mindoro, Philippines was felt with intensity II-III in the area(s) of Mindoro, Philippines in Southern Tagalog at Cnenca and Indang (IV) and Calantas, Mahabang, Luksuhin, Tagayhlay, Malabag and Dainta. PHIVOLCS reported this quake with M 5.0 was felt with intensity IV in the Philippines in Mabini, San Luis, Lemery, Rosario, Agoncillo, Calatagan, Balayan, Bauan, Sta. Teresita, Batangas; Tagaytay City, Alfonso and Amadeo, Cavite; III in Batangas City; Malvar, Talisay, Tanauan, Alitagtag Batangas; San Pablo, Luguna; II in Quezon City; Mandaluyong City, Navotas City, Majayjay, Laguna, Dolores, Quezon and I in Malabon City; Pasay City; Sta. Cruz, Laguna.

An aftershock of M 4.4 was reported felt in the same area. This earthquake may have been triggered by low atmospheric pressures associated with Typhoon Molave which passed over the epicenter two days ago as noted in this summary:

 

"Typhoon Molave (TD 21W) continued today west of Samar, Philippines winds up to 125 kts. It is expected to track to the west over the next several days reaching southeastern Asia around October 29 as a typhoon. Seismicity in Southern Asia is expected to be enhanced by stresses from this storm as it makes landfall." (October 25-27, 2020)

 

Forecast 128131 had expected today's activity was likely within about 100 km around October 25.

 

O: 29OCT2020 05:25:43  13.8N  120.9E mb=4.8  EMSC   MINDORO, PHILIPPINES         

P: 25OCT2020 128131    13.0N  122.0E 3.5-4.8 BAAAA  Luzon, Philippines         

 

SOLAR FLARES PROMOTE HIGH AND LOW LATITUDE SEISMICITY

 

EARTHQUAKE SUMMARY FOR OCTOBER 27, 2020

 

A series of moderate solar flares continued today. This included a C4.3 event, the strongest solar flare observed since late May 29, 2020 when a C9.3 and an M1.1 were observed. Previous issues of this summary had expected seismic enhanced associated with this and the current geomagnetic storm at this time as:

 

"This is the strongest disturbance in the  geomagnetic field since September 28.  Strong disturbances in the geomagnetic field can help promote seismicity and may do so at high latitudes with this storm.." (October 25-27, 2020)

 

The C4.3 solar flare occurred near local solar midnight along the western coast of South America and may have helped promote an M 5.5 in Maule, Chile today. An M 5.5 in Sulawesi, Indonesia at the opposite longitude (local solar noon) may also have been promoted this solar/geomagnetic activity. The parameters of today's M 4.3 follow:

 

Flare #    START  MAX       END    CLASS     DATE    Flux (Jm-2)

#-------------------------------------------------------------------------------

7480       0611   0616      0621   C4.3      (October 27, 2020)   1.3E-03  

 

A moderately strong earthquake of M 5.5 shook regions of Maule, Chile today. NEIC reported maximum intensity V in Maule at Constitucion and IV in Curico, Molina, Teno, Talca, and in O'Higgins at Santa Cruz, Chimbarongo, and San Vicento and II-III in San Fernando and San Javier.  GUC reported this earthquake was felt with intensity  VI in  Maule, at Constitucion; V in Curepto, Curico, Linares, Maule, Pencahue, Romeral, Sagrada Familia, San Clemente, Talca and Yerbas Buenas; IV in San Javier, Villa Alegre and III in Cauquenes; in O'Higgins with V in Rancagua and San Fernando and Peralillo and IV in Las Cabras, Navidad, Paredones, Pichilemu, Rengo and Requinoa; in Nuble with III in Chillan, Cobquecura and Trehuaco; in Biobio with III in Cabrero, Chiguayante, Concepcion, Los Angeles, Talcahuano and Tome; in Santiago with IV in Maria Pinto and Paine and III in Penaflor, Puente Alto, Santiago and Tiltil and in Valparaiso with II in Cartagena dn Santo Domingo, Chile. The last earthquake within about 150 km of this epicenter with M>=5.5 was an M 6.8 to the northwest of this on August 1, 2019 and an aftershock of M 5.8. Forecast 128295 had expected today's activity was likely around October 26.

 

 

O: 28OCT2020 04:52:31  34.9S   71.7W Mw=5.5  EMSC   MAULE, CHILE                 

O: 28OCT2020 04:52     34.9S   71.7W mb=5.5  GUC    Maule, at Constitucion; V in C

P: 26OCT2020 128295    31.0S   68.0W 4.0-5.3 ACCAA  Central Chile              

 

An earthquake of M 5.5 also occurred today in the region of Sulawesi, Indonesia. NEIC reported it was felt with intensity III in Rantepac, Sulawesi, Indonesia. This epicenter is near the fourth node (90 degrees) from the M 5.5 in Alaska of October 19 and near the geomagnetic equator, and may have been enhanced by energy from both these sources. An M 5.8 occurred about 150 km northeast of this epicenter on March 28, 2020 but the last within about 100 km of M>=5.5 was an M 5.5 two years ago on November 14, 2018. An M 7.5 hit the area about 250 km northeast of today's epicenter on September 28, 2018. Forecasts 128103 and 128116 had expected today's activity in late October. This activity is at 144 degrees  from the M 6.8 in the central Atlantic of September 18 and may have been promoted by energy from that source.

 

O: 27OCT2020 19:43:55   2.3S  119.2E Mw=5.5  EMSC   SULAWESI, INDONESIA

O: 27OCT2020 21:00:40   2.3S  119.1E ML=4.6  EMSC   SULAWESI, INDONESIA

O: 27OCT2020 22:50:35   2.4S  119.1E mb=4.4  EMSC   SULAWESI, INDONESIA

O: 27OCT2020 18:28:27   1.2S  119.5E ML=4.3  EMSC   SULAWESI, INDONESIA          

P: 28OCT2020 128103     2.0N  118.0E 3.5-4.9 ACBAA  Malaysia                    

P: 31OCT2020 128116     2.0S  123.0E 4.0-5.3 BACAA  Sulawesi area              

 

The strongest earthquake in the U.S. or Canada today was an M 5.5 in the Andreanof Islands, Aleutians. It was probably promoted by tidal and geomagnetic stresses as discussed above. This is the strongest intermediate depth earthquake in the eastern Andreanof Islands since an M 6.1 on February 26, 2014 and the strongest at any depth within about 200 km of this epicenter since that event. It was not reported felt in the area. Forecast 128239 had expected today's event in this area was likely around October 26. This epicenter is at the third node (120 degrees) from the M 6.8 in Atacama, Chile of September 1 and may have been promoted by energy from that source.

 

O: 28OCT2020 04:13:41  53.3N  173.5W Mw=5.5  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 26OCT2020 128239    52.1N  174.3W 3.5-4.8 AAAAA  Andreanoff Isls, Aleutians 

 

An unusual earthquake of M 4.9 occurred off the east coast of South Island, New Zealand today. NEIC reported this event was felt with intensity IV in Wellington and II-III in Blenheim, Picton, Lower Hutt, Cheviot, Amberley, Rangora and Christchurch, New Zealand. Felt with strong intensity in the area of Blenheim, New Zealand and in southern North Island and northern South Island. 1699 reported feeling this earthquake. Of these, 1093 felt it with weak intensity; 566 with light intensity; 39 with moderate shaking and 1 with extreme intensity. This epicenter is at 100 degrees from the epicenter of the M 7.5 in the Alaska

Peninsula of October 19 and M 7.8 of July 22 and from the Oaxaca, Mexico quake of June 23, 2020 and was likely promoted by concentrated energy from those sources. An M 4.9 in the Central mid-Atlantic occurred at a similar distance from the Alaska Peninsula today. The last earthquake with M>=4.9 within about 100 km of today's epicenter was an M 6.5 to the west of this and aftershocks on November 14-15, 2016. Forecast 128303 had expected today's event to the north was likely around October 28.

 

O: 28OCT2020 03:01:37  42.3S  174.7E mb=4.9  EMSC   OFF E. COAST OF S. ISLAND, N.Z

O: 28OCT2020 03:01:38  42.2S  174.6E MS=4.8  GEONET Felt with strong intensity

P: 28OCT2020 128303    41.0S  175.0E 3.0-4.8 ABAAA  So. Island, N.Z.           

 

Seismicity in the South Shetland Islands continued unabated today. Two moderate earthquakes of M 4.8 and 4.5 were reported in the area today. The M 4.8 occurred within about 15 minutes of local solar noon and was probably promoted by strong tidal stresses which maximize near this hour. The full moon will be arriving in three days at this time of day in the South Shetland Islands and will probably continue to promote regional seismicity over the next several days as noted in this summary:

 

"The full moon will arrive on October 31 at 14:49 UT. Longitudes which are sub-solar at this time are near 40 West and 140 East. These include the central Atlantic in the west and Japan and much of the eastern Pacific Rim from Kamchatka to New Guinea in the east. These areas may see moderate seismic enhancement over the next seven days to to enhanced tidal stresses." (October 27-28, 2020)

 

Forecast 128309 had expected today's activity in the South Shetland Islands was

likely around October 25.

 

O: 27OCT2020 14:38:42  62.4S   58.3W mb=4.8  EMSC   SOUTH SHETLAND ISLANDS

O: 27OCT2020 11:13:49  62.3S   58.3W mb=4.5  EMSC   SOUTH SHETLAND ISLANDS       

P: 25OCT2020 128309    61.0S   58.0W 4.0-5.4 ABAAA  So. Shetland Is.           

 

MODERATE EARTHQUAKES SHAKES CENTRAL IRAN

 

EARTHQUAKE SUMMARY FOR OCTOBER 26, 2020

 

The strongest earthquake in the world today was a moderate event - of a mere M 5.0 - in Central Iran. This is an unusual epicenter. The last earthquake within about 200 km of this epicenter with M>=5 was an M 5.2 on December 21, 2017 and prior to that an M 5.0 on August 27, 2013 with M 5.0. An M 5.1 hit about 500 km northwest of this epicenter two days ago on October 24, 2020. At the time this summary noted in this regard:

 

 

"An earthquake of M 5.0 (M 5.1) was widely felt in western Iran today. NEIC reported maximum shaking with intensity IV in Iran at Abhar Oazvin, Khorram Darreh and Ecbatana and II-III in Sandjan, Oazvin, Resht, Teheran. This is the strongest earthquake within about 200 km of this epicenter since an M 5.4 on May 27, 2008. Forecast 128187 had expected today's event was likely within about 25 km of this epicenter around October 24." (October 24, 2020)

 

NEIC reported this earthquake of M 5.0 in Iran  was felt with intensity II-III in the area(s) of  Iran at Bafgh, Yazd and Kirman, Kerman. Forecast 128164 had expected today's event to the northeast was possibly around October 23.

 

O: 26OCT2020 21:34:51  32.2N   56.1E mb=5.0  EMSC   CENTRAL IRAN                 

P: 23OCT2020 128164    33.0N   60.0E 3.8-5.2 BACAA  Afghanistan                

 

Aftershocks continued today in the region of Switzerland with the largest of these M 2.3 and 2.6. In the previous issue of this summary this swarm was noted as:

 

"An unusual M 4.3-4.5 was widely felt in eastern Switzerland today. It was followed by a number of smaller aftershocks. NEIC reported the mainshock was felt with maximum intensity IV in Switzerland at Glarus and Nafels and III in Ennenda, Filzbach, Linthal, Sargana, Braunwald, Flims, Bad Ragaz and Wartau among others. The last earthquake in Switzerland with M>=4.3 was an M 4.5 more than ten years ago on January 4, 2009 and prior to that an M 4.4  on November 12, 2005. Forecast 128210 had expected today's earthquake was likely in this region around October 27. This activity is at 103 degrees from the M 6.8 in Atacama, Chile of September 1 and was probably promoted by strong, concentrated energy from that source. An earthquake of M 3.6 in southeastern Alaska today was also at this distance from Atacama, Chile." (October 25, 2020)

 

O: 27OCT2020 06:54:45  46.9N    9.2E ML=2.3  EMSC   SWITZERLAND

O: 27OCT2020 03:40:44  46.9N    9.1E ML=2.6  EMSC   SWITZERLAND                  

P: 27OCT2020 128210    46.0N    8.0E 3.0-4.9 AAAAA  Austria                    

 

The strongest earthquakes in the U.S. or Canada today occurred in the area of the aftershock zone of the M 7.8 in the Alaska Peninsula of October 19. Some of these were lightly felt in Sandy Cove, Alaska. These included events of M 4.9, 4.6 and 4.3. Forecast 128237 had expected today's activity was likely around October 25.

 

O: 27OCT2020 04:52:17  54.3N  159.7W mb=4.3  EMSC   SOUTH OF ALASKA

O: 26OCT2020 07:40:18  54.5N  159.9W mb=4.6  EMSC   SOUTH OF ALASKA

O: 26OCT2020 19:51:07  54.6N  159.7W ml=3.3  EMSC   SOUTH OF ALASKA

O: 26OCT2020 09:25:09  54.8N  160.4W mb=4.9  EMSC   ALASKA PENINSULA

O: 26OCT2020 14:13:02  54.0N  159.6W ml=3.7  EMSC   SOUTH OF ALASKA              

P: 25OCT2020 128237    54.7N  159.5W 3.5-4.9 AAAAA  Alaska Peninsula           

 

The moderate swarm of events in Hawaii continued today with at least five events of M 2.5. In the previous issue of this summary this summary was iscussed as:

 

 

"The swarm of earthquakes in Hawaii continued unabated today. The strongest earthquake in the region today was an M 3.5 and M 4.2. NEIC reported it was felt with intensity IV in Hawaii in Pahala and II-III in Naalehu, Volcano, Pahoa, Captain Cook, Mountain View, Hilo, Kurtistown, Keaau and Paauilo. The last earthquake of M>=4.2 occurred as an M 4.2 on August 1, 2020, the last such event of M>3.5 was an M 3.6 on August 16, 2020. Forecast 128128 had expected today's events within about 25 km of these epicenters were likely around October 24." (October 26, 2020)

 

O: 26OCT2020 19:24:28  19.2N  155.5W ML=2.5  EMSC   ISLAND OF HAWAII, HAWAII

O: 27OCT2020 04:37:18  19.3N  155.4W ML=2.6  EMSC   ISLAND OF HAWAII, HAWAII

O: 27OCT2020 03:56:00  19.4N  155.2W ML=2.7  EMSC   ISLAND OF HAWAII, HAWAII

O: 26OCT2020 13:10:23  19.5N  155.7W ML=2.7  EMSC   ISLAND OF HAWAII, HAWAII

O: 26OCT2020 08:01:35  19.1N  155.4W Ml=2.5  EMSC   ISLAND OF HAWAII, HAWAII     

P: 24OCT2020 128128    19.3N  155.2W 4.0-5.3 AAAAA  Hawaii area                

 

MODERATE QUAKES FELT IN SAMOA AND NORTHERN CHILE LINKED TO ALASKA PENINSULA

 

EARTHQUAKE SUMMARY FOR OCTOBER 25, 2020

 

The strongest earthquake in the world today was an M 5.9 in the region of Samoa.

NEIC reported this earthquake was felt with intensity IV in Samoa at Siusega, Northwest Upolu and ini American Samao and III in Halalo Mua Wallis and Futuna. This earthquake is located at the fifth node (72 degrees) from the M 7.5 in  the Alaska Peninsula of October 19 and probably was promoted by energy from this source. In addition it is located at 144 degrees from the M 6.8 in the Mid-Atlantic of September 18 and was also subject to energy from that source. Three earthquakes at this magnitude level have occurred in the region of Samoa in the past year - all of M 6.0 on July 18, March 17, 2020 and December 6, 2019. The last event of significantly larger magnitude in the area was an M 6.8 on November 4, 2017. Forecasts 128280 and 128274 had expected today's event was likely in the region of Tonga/Samoa between October 24 and 27.

 

This had been expected as a far-field aftershock of the Alaska Peninsula event in previous issues of this summary as:

 

"72 degrees (node 5): Alaska Peninsula to ... Samoa" (October 19, 2020)

 

Other earthquakes today at 72 degrees from the Alaska Peninsula epicenter occurred in New Britain (M 4.9); the Solomon Islands (M 5.1); and Nicaragua (M 4.1).

 

O: 25OCT2020 11:47:36  15.4S  173.5W Mw=5.9  EMSC   TONGA                        

P: 24OCT2020 128280    16.0S  175.0W 4.0-5.3 AABAA  Tonga Islands              

P: 27OCT2020 128274    15.0S  175.0W 4.0-5.3 AABAA  Samoa Islands              

 

The strongest earthquake in the world widely felt today was an M 5.4 in northern Chile. NEIC reported it was felt with intensity III in Iquique, Tarapaca, Chile.

GUC reported this earthquake was felt with intensity  IV in  Tarapaca at Huara, La Tirana; III in Alto Hospicio, Camina, Iquique, Pica and Pozo Almonte, Chile. This epicenter is at 105 degrees from the epicenter of the M 7.5 in the Alaska

Peninsula of October 19. Seismic energy concentrates at this distance from large surface events and can help promote further seismicity in this distance zone. The last earthquake within about 200 km of today's M 5.4 with greater or equal magnitude occurred on September 11, 2020 with M 6.3 and before that as an M 5.5 on August 3, 2020. That event appears to have been triggered by strong energy from the M 7.8 in the Alaska Peninsula of July 22. Forecast 128290 had expected today's event was likely around October 27.

 

This had been expected as a far-field aftershock of the Alaska Peninsula event in previous issues of this summary as:

 

"101-104 degrees (node 7): Alaska Peninsula to ... northern Chile" (October 19, 2020)

 

O: 25OCT2020 13:38:50  18.6S   69.6W mb=4.1  EMSC   TARAPACA, CHILE              

O: 25OCT2020 21:29:24  20.1S   71.0W mb=4.5  EMSC   OFF COAST OF TARAPACA, CHILE

O: 25OCT2020 21:17:16  20.0S   70.9W Mw=5.4  EMSC   OFFSHORE TARAPACA, CHILE     

O: 25OCT2020 21:17     20.0S   71.2W mb=5.3  GUC    Tarapaca at Huara, La Tirana;

P: 27OCT2020 128290    20.0S   70.0W 4.0-5.3 AAAAA  So. Peru/Bolivia           

 

An unusual M 4.3-4.5 was widely felt in eastern Switzerland today. It was followed by a number of smaller aftershocks. NEIC reported the mainshock was felt with maximum intensity IV in Switzerland at Glarus and Nafels and III in Ennenda, Filzbach, Linthal, Sargana, Braunwald, Flims, Bad Ragaz and Wartau among others. The last earthquake in Switzerland with M>=4.3 was an M 4.5 more than ten years ago on January 4, 2009 and prior to that an M 4.4  on November 12, 2005. Forecast 128210 had expected today's earthquake was likely in this region around October 27. This activity is at 103 degrees from the M 6.8 in Atacama, Chile of September 1 and was probably promoted by strong, concentrated energy from that source. An earthquake of M 3.6 in southeastern Alaska today was also at this distance from Atacama, Chile.

 

O: 25OCT2020 19:43:10  46.9N    9.1E ML=3.6  EMSC   SWITZERLAND

O: 25OCT2020 22:23:35  46.9N    9.1E ML=3.2  EMSC   SWITZERLAND

O: 25OCT2020 19:43:46  47.5N    7.9E ML=2.7  EMSC   SWITZERLAND

O: 25OCT2020 19:35:43  46.9N    9.1E ML=4.3  EMSC   SWITZERLAND                  

P: 27OCT2020 128210    46.0N    8.0E 3.0-4.9 AAAAA  Austria                     

 

The swarm of earthquakes in Hawaii continued unabated today. The strongest earthquake in the region today was an M 3.5 and M 4.2. NEIC reported it was felt with intensity IV in Hawaii in Pahala and II-III in Naalehu, Volcano, Pahoa, Captan Cook, Mountain View, Hilo, Kurtistown, Keaau and Paauilo. The last earthquake of M>=4.2 occurred as an M 4.2 on August 1, 2020, the last such event of M>3.5 was an M 3.6 on August 16, 2020. Forecast 128128 had expected today's events within about 25 km of these epicenters were likely around October 24.

 

O: 25OCT2020 13:08:54  19.4N  155.4W ML=3.1  EMSC   ISLAND OF HAWAII, HAWAII

O: 26OCT2020 04:02:33  19.2N  155.4W ML=4.2  EMSC   ISLAND OF HAWAII, HAWAII     

P: 24OCT2020 128128    19.3N  155.2W 4.0-5.3 AAAAA  Hawaii area                

 

Moderate earthquakes including an M 4.0 and 3.5 were also widely felt in the aftershock zone of southwestern Puerto Rico. An M 3.5 was felt with intensity IV in Puerto Rico at Guanica, Lajas, San German and Cabo Rojo and II-III in Sabana Grande, Yauco, Penuelas and Mayaguez. Forecasts 128142 and 128144 had expected this activity was likely between October 25 and 29.

 

O: 26OCT2020 01:39:48  18.0N   67.0W mb=4.2  EMSC   PUERTO RICO                  

P: 25OCT2020 128144    19.0N   66.0W 3.4-5.1 AAAAA  Puerto Rico                

P: 29OCT2020 128142    18.0N   67.0W 3.4-4.8 BAAAA  Puerto Rico                

 

Moderate earthquakes also continued today in the Alaska Peninsula area. They were reported with intensity III in Sand Point, Alaska. Forecast 128237 had expected continued aftershocks in the area around October 25.

 

 

O: 25OCT2020 18:08:46  54.3N  159.7W ML=3.6  EMSC   SOUTH OF ALASKA

O: 25OCT2020 16:53:43  54.4N  159.7W mb=3.8  EMSC   SOUTH OF ALASKA

O: 25OCT2020 22:46:06  54.4N  159.6W ml=3.5  EMSC   SOUTH OF ALASKA

O: 25OCT2020 08:25:28  54.6N  159.6W ml=3.3  EMSC   SOUTH OF ALASKA

O: 25OCT2020 12:38:53  54.9N  160.3W ml=3.6  EMSC   ALASKA PENINSULA

O: 26OCT2020 01:28:04  53.6N  159.7W ml=3.3  EMSC   SOUTH OF ALASKA               

P: 25OCT2020 128237    54.7N  159.5W 3.5-4.9 ABAAA  Alaska Peninsula           

 

STRONG QUAKE SHAKES JAVA, INDONESIA

 

EARTHQUAKE SUMMARY FOR OCTOBER 24, 2020

 

The strongest earthquake in the world today was an M 5.4-5.9 south of Java, Indonesia. NEIC reported maximum intensity was felt with V in Java at Kadungora with II-III shaking in Ciparay, Bandung, Wengon, Batu Japar, Padalarang and Karawang, Java. BMG reported this with magnitude M 5.9. They reported intensity III-IV in Sukabumi, Tasikmalaya, Pangandaram; II-III in Cilacap , Kabupaten Bandung, Banyumas, Kutoarjo, Kebumen, Banjarnegara, Kulonprogo, Bantul, Sunung Kidul, Yogyakarta; III in Cilacap, Garut and II in Bandung and Tegal, Java, Indonesia. This earthquake at 99 degrees from the Alaska Peninsula quake of M 7.5 on October 19 was probably promoted by energy from that source. The last earthquakes within about 200 km of this epicenter occurred as an M 5.6 on May 18,, 2019 and an M 5.4 on December 16, 2017 - an aftershock of M 6.5 on December 15, 2017 within about 50 km of today's epicenter. Forecast 128116 had expected today's event was likely within about 100 km of the event around October 24. This earthquake is at 144 degrees from the M  6.8 in Atacama, Chile of September 1 and was probably promoted by energy from that source.

 

O: 25OCT2020 00:56:49   7.9S  108.1E Mw=5.4  EMSC   JAVA, INDONESIA              

P: 24OCT2020 128116     9.0S  108.0E 4.0-5.3 ABAAA  Java                       

 

An earthquake of M 5.0 was widely felt in western Iran today. NEIC reported maximum shaking with intensity IV in Iran at Abhar Oazvin, Khorram Darreh and Ecbatana and II-III in Sandjan, Oazvin, Resht, Teheran. This is the strongeset earthquake within about 200 km of this epicenter since an M 5.4 on May 27, 2008. Forecast 128187 had expected today's event was likely within about 25 km of this epicenter around October 24.

 

O: 24OCT2020 11:34:18  35.7N   49.0E mb=5.1  EMSC   WESTERN IRAN                 

P: 24OCT2020 128187    36.0N   49.0E 3.8-5.1 AAAAA  No. Iran                   

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 aftershock near the Alaska Peninsula. NEIC reported it was felt with intensity III in Sand Point, Alaska. The M 4.8 today occurred within minutes of local solar noon and was probably promoted by strong tidal stresses which maximize near this hour.

Forecast 128237 had expected today's activity was likely around October 25.

 

O: 24OCT2020 10:41:33  54.2N  159.8W ml=3.2  EMSC   SOUTH OF ALASKA

O: 25OCT2020 04:41:23  54.2N  159.7W ml=3.3  EMSC   SOUTH OF ALASKA

O: 24OCT2020 13:02:14  54.4N  159.7W ml=3.5  EMSC   SOUTH OF ALASKA

O: 24OCT2020 22:52:35  54.4N  159.6W ml=3.5  EMSC   SOUTH OF ALASKA

O: 24OCT2020 12:35:18  54.5N  159.6W mb=4.1  EMSC   SOUTH OF ALASKA

O: 24OCT2020 20:36:44  54.5N  159.6W ml=3.2  EMSC   SOUTH OF ALASKA

O: 24OCT2020 21:42:05  54.6N  159.8W Mw=4.1  EMSC   SOUTH OF ALASKA

O: 24OCT2020 22:23:00  54.6N  159.6W Mw=4.8  EMSC   SOUTH OF ALASKA

O: 25OCT2020 03:32:32  54.1N  159.7W ml=3.4  EMSC   SOUTH OF ALASKA              

P: 25OCT2020 128237    54.7N  159.5W 3.5-4.9 AAAAA  Alaska Peninsula           

 

A similar M 4.8 in the Gulf of Alaska today may have been felt in Homer, Alaska.

An M 5.1 hit this area on March 20, 2020 and was noted in this summary at the time as:

 

"The largest quake in Alaska was an M 5.1 in the Gulf of Alaska. It was reported by NEIC to have been felt with weak intensity in Alaska at Kodiak, Homer, Seward, Anchorage and Chugiak. This is the largest aftershock in the Gulf of Alaska of the M 7.9 of January 23, 2018" (March 21, 2020)

 

Forecast 128032 had expected today's earthquake within about 100 km of the epicenter was likely around October 17.

 

O: 24OCT2020 19:58:16  56.0N  149.3W ml=3.3  EMSC   GULF OF ALASKA               

O: 24OCT2020 17:58:49  56.4N  147.6W Mw=4.8  EMSC   GULF OF ALASKA               

P: 17OCT2020 128032    56.0N  149.0W 3.0-4.5 CAAAA  Northern Alaska            

 

The series of moderate earthquakes in the Northwest Territories, Canada continued today with events of M 4.5-4.7 and M 4.0. This continues recent activation of this epicenter which included an M 5.1 on October 14 and an M 4.3 on October 18. The only other event in the region in the past year with M>=4.7 occurred as an M 4.7 on July 25, 2020, three days after the M 7.8 mainshock in the Alaska Peninsula. At the time this summary noted in this regard:

 

"..an M 4.7-5.3 in Northwest Territories today since the Alaska earthquake. Both appear to have been promoted by energy from the Alaska earthquake." (July 25, 2020)

 

The strongest earthquake in the U.S. or Canada today was an M 4.3-4.8 in the region near Wrigley, Northwest Territories, Canada. This continues activity in the area which has been discussed in the past several issues of this summary as:

 

and

 

"The strongest earthquake in the U.S. or Canada  today was an M 4.4 in the Northwest Territories of Canada. The only earthquake in the past six years within about 300 km of this epicenter with M>=4.4 was an M 4.7 on July 25, 2020. Prior to that earthquakes of M 4.4 and 4.5 occurred in March and July, 2014 in this area. The strongest earthquake in this area in the past 30 years was an M 5.6 on June 10, 1990.  Forecast 127772 had expected today's event was likely within about 50 km of this epicenter was likely around October 10." (October 15, 2020)

 

Forecast 128034 had expected today's activity was likely within about 25 km  of this epicenter around October 22.

 

O: 24OCT2020 17:18:27  62.2N  124.4W mb=4.0  EMSC   NORTHWEST TERRITORIES, CANADA

O: 24OCT2020 17:18:30  62.2N  124.6W MB=4.0  ECAN OF WRIGLEY, NT   

O: 24OCT2020 16:18:00  62.2N  124.4W MB=4.5  ECAN of Wrigley, NT   

O: 24OCT2020 16:18:48  62.2N  124.6W mb=4.7  EMSC   NORTHWEST TERRITORIES, CANADA

P: 22OCT2020 128034    62.1N  124.2W 2.5-3.8 AAAAA  Northwest Terr., Canada    

 

The strongest earthquake in the current Hawaiian swarm occurred today with M 3.5-3.7. NEIC reported it was felt with intensity II-III in Hawaii at Hawaii National Park, Volcano, Hilo and Pepeekeo. In the previous summary it had been noted in this regard:

 

"A strong swarm of light earthquakes occurred in Hawaii today. The strongest of these was an M 3.0-3.3 which NEIC reported was felt with intensity III in Hawaii National Park and Volcano, Hawaii. Forecasts 127882 and 128128 had expected this activity in mid-October within about 25 km of the swarm. This activity is at the 10th node (36 degrees) from the Alaska Peninsula earthquake of M 7.5 of October 19 and may have been promoted by energy from that source. It is also at 104 degrees from the M 6.8 in Sumatra of August 18, 2020 and was probably promoted by concentrated energy from that source." (October 23-24, 2020)

 

A listing of events in this swarm of M>=2.5 follows. A more complete listing can be found under the regional "HAWAII" section of this report:

 

O: 24OCT2020 10:10:08  19.4N  155.3W ML=2.6  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 11:46:44  19.4N  155.3W Ml=2.8  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 13:08:49  19.4N  155.3W ML=2.7  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 13:08:49  19.4N  155.3W ML=2.7  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 13:33:53  19.4N  155.3W ML=2.5  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 15:06:48  19.4N  155.3W ML=2.9  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 15:08:45  19.4N  155.3W ML=3.7  EMSC   ISLAND OF HAWAII, HAWAII

O: 24OCT2020 15:14:22  19.4N  155.3W ML=2.9  EMSC   ISLAND OF HAWAII, HAWAII

P: 24OCT2020 128128    19.3N  155.2W 4.0-5.3 AAAAA  Hawaii area                

 

An unusually large M 2.8-3.2 earthquake was widely felt in Virginia and North Carolina today. This is likely the largest aftershock to date of an M 5.1 which hit near this epicenter on August 9, 2020. It had been expected within about 100 km of this epicenter in forecast 128181. When the mainshock occurred in August, this summary noted in this regard:

 

"An earthquake of M 5.1 shook large areas of eastern U.S. today. This event was centered on the North Carolina-Virginia border. It was reported by nearly 100,000 persons to NEIC. … While lighter foreshocks of M 2.2 and 2.1 occurred about a day earlier … The last earthquake of similar or larger magnitude in the area was an M 5.2 on 1916 in the Great Smoky Mountains. The earthquake of August, 2011 near Mineral, Virginia of M 5.8 was one of the largest in east coast history and did extensive damage as far as Washington, D.C. A series of foreshocks hit the region in the day prior to the mainshock with M 2.1-2.6.

 

Hurricane Isaias passed near this epicenter 5-6 days ago and stresses associated with that storm, the second in the region this year (following TS Arthur on May 17-18, 2020), probably enhanced the likelihood of today's seismicity." (August 9, 2020)

 

NEIC reported this earthquake of M 2.8 on the Virginia-North Carolina border  was felt with intensity II-III in the area(s) of the Virginia-North Carolina border with IV in Sparta and Glade Valley, North Carolina and II-III in North Carolina at Ennice, Laurel Springs, Traphill, Hays, Piney Creek and in Virginia at Fries (IV) and Independence, Galax.

 

O: 25OCT2020 03:08:32  36.5N   81.1W mb=3.2  EMSC   VIRGINIA-N CAROLINA BORDER REG

P: 24OCT2020 128181    37.2N   81.9W 2.0-3.8 AAAAA  Kentucky/Tennessee/NC      

 

The largest earthquake in the Americas outside Alaska today was an M 4.7 near La Paz, Bolivia. This epicenter is at 103 degrees from the M 7.5 in the Alaska Peninsula of October 19. Forecast 128278 had expected today's event was likely around October 28.

 

O: 24OCT2020 15:52:32  17.7S   69.3W mb=4.7  EMSC   LA PAZ, BOLIVIA              

P: 28OCT2020 128278    18.0S   71.0W 4.0-5.4 BABAA  So. Peru/Bolivia           

STRONG EARTHQUAKE IN FIJI; SWARM IN HAWAII

 

EARTHQUAKE SUMMARY FOR OCTOBER 23, 2020

 

The strongest earthquake in the world today was an M 6.1 in the Fiji Islands. It was not reported felt in this remote area. An M 4.7 foreshock hit the area north of this near local solar noon. This is the strongest earthquake within about 200 km of this epicenter since an M 6.5 on September 16, 2018. Forecast 128072 had expected today's activity in this area was likely around October 19. This activity is located at 144 degrees from the Atlantic Ocean event of M 6.8 of September 18, 2020 and may have been promoted by energy from this source.

 

 

O: 23OCT2020 07:04:31  25.7S  179.9W ML=6.1  EMSC   SOUTH OF FIJI ISLANDS        

O: 23OCT2020 07:04:32  25.6S  180.0W mw=6.1  ANSS   the Fiji Islands             

P: 23OCT2020 128294    23.0S  179.0E 4.0-5.4 ACAAA  Tonga/Fiji                 

P: 25OCT2020 128271    24.0S  179.0E 4.0-5.3 ABAAA  Fiji Islands               

P: 19OCT2020 128072    23.0S  179.0E 4.0-5.4 ABAAA  Tonga/Fiji                 

P: 21OCT2020 128065    29.0S  178.0W 4.0-5.4 ACAAA  No. Kermadec Islands       

 

A strong swarm of light earthquakes occurred in Hawaii today. The strongest of these was an M 3.0-3.3 which NEIC reported was felt with intensity III in Hawaii National Park and Volcano, Hawaii. Forecasts 127882 and 128128 had expected this activity in mid-October within about 25 km of the swarm. This activity is at the 10th node (36 degrees) from the Alaska Peninsula earthquake of M 7.5 of October 19 and may have been promoted by energy from that source. It is also at 104 degrees from the M 6.8 in Sumatra of August 18, 2020 and was probably promoted by concentrated energy from that source. A listing of events in this swarm of M>=2.5 follows:

 

O: 23OCT2020 09:05:01  19.4N  155.3W ML=2.9  EMSC   ISLAND OF HAWAII, HAWAII

O: 23OCT2020 10:13:39  19.4N  155.3W ML=2.9  EMSC   ISLAND OF HAWAII, HAWAII

O: 23OCT2020 11:08:06  19.4N  155.3W ML=2.5  EMSC   ISLAND OF HAWAII, HAWAII

O: 23OCT2020 11:24:11  19.4N  155.3W ML=2.5  EMSC   ISLAND OF HAWAII, HAWAII

O: 23OCT2020 11:43:42  19.4N  155.3W ML=3.3  EMSC   ISLAND OF HAWAII, HAWAII

O: 23OCT2020 08:48:37  19.4N  155.3W ML=2.6  EMSC   ISLAND OF HAWAII, HAWAII     

P: 15OCT2020 127882    19.2N  155.2W 3.0-4.3 CAAAA  Hawaii                     

P: 24OCT2020 128128    19.3N  155.2W 4.0-5.3 AAAAA  Hawaii area                

 

The strongest earthquakes in the U.S. or Canada today continued as aftershocks of the M 7.5 in the Alaska Peninsula of October 19. The largest of these today were an M 4.6 and M 4.3. The M 4.6 occurred within minutes of local solar midnight and was probably promoted by tidal stresses associated which maximize near this hour. Forecast 128237 had expected today's activity was likely around October 25.

 

O: 23OCT2020 07:21:22  54.2N  159.6W ml=3.6  EMSC   SOUTH OF ALASKA

O: 24OCT2020 06:50:06  54.2N  159.7W mb=4.1  EMSC   SOUTH OF ALASKA

O: 23OCT2020 10:58:13  54.6N  159.7W Mw=4.6  EMSC   SOUTH OF ALASKA

O: 23OCT2020 12:27:45  54.1N  159.7W mb=4.3  EMSC   SOUTH OF ALASKA              

P: 25OCT2020 128237    54.7N  159.5W 3.5-4.9 AAAAA  Alaska Peninsula           

 

STRONG QUAKES IN FIJI; SOUTH CHILE RISE

 

EARTHQUAKE SUMMARY FOR OCTOBER 22, 2020

 

The strongest earthquakes in the world today were located in the West Chile Rise (M 6.0) and in the area south of Fiji (M 6.1). The M 6.0 followed a smaller event south of this in the West Chile Rise about 3.5 hours earlier. Neither of these earthquakes were reported felt in these regions. The M 6.0 in the northern West Chile Rise occurred six years ago on May 6, 2014 and prior to that an M 6.3 on November 29, 2007. Forecast 128082 had expected this activity within about 50 km of this epicenter was likely around October 16, 2020. This epicenter is at 105 degrees from the M 7.8 in the Alaska Peninsula of October 19. It was probably promoted by strong concentration of energy from the Alaska event.

 

O: 23OCT2020 01:46:17  36.3S   97.2W Mw=6.0  EMSC   WEST CHILE RISE              

P: 16OCT2020 128082    36.0S   97.0W 4.0-5.3 CAAAA  Chile Rise                 

 

The foreshock in the West Chile Rise south of the M 6.0 of M 4.3 was the strongest within about 200 km of this epicenter since an M 4.7 on June 8, 2020. Forecast 128082 had expected this event within about 200 km of this epicenter was likely around October 22. This epicenter is located at the third node (120 degrees) from the Alaska Peninsula  of M 7.8 on October 19 and was probably enhanced by energy from that source.

 

O: 22OCT2020 22:24:52  44.7S   81.3W mb=4.3  EMSC   WEST CHILE RISE              

P: 22OCT2020 128082    43.0S   83.0W 4.0-5.5 AABAA  Chile Rise                  

 

An M 6.1 also hit the area south of the Fiji Islands today. It was not  reported felt in the area. An M 4.7 foreshock hit the area north of this near local solar noon. This is the strongest earthquake within about 200 km of this epicenter since an M 6.5 on September 16, 2018. Forecast  128072 had expected today's activity in this area was likely around October 19. This activity is located at 144 degrees from the Atlantic Ocean event of M 6.8 of September 18, 2020 and may have been promoted by energy from this source.

 

O: 23OCT2020 00:59:09  24.7S  179.4E mb=4.7  EMSC   SOUTH OF FIJI ISLANDS        

O: 23OCT2020 07:04:31  25.7S  179.9W ML=6.1  EMSC   SOUTH OF FIJI ISLANDS        

P: 19OCT2020 128072    23.0S  179.0E 4.0-5.4 ABAAA  Tonga/Fiji                  

 

An M 5.7-5.8 also occurred north of these in the Fiji Islands. It was not reported felt in the area. An earthquake of M 6.0 occurred about 200 km west of this on July 21, 2020 but the last within 200 km of today's epicenter was an M 6.4 on December 23, 2018.  Forecast 128070 had expected today's activity was likely within about 100 km of this epicenter around October 21.

 

O: 22OCT2020 08:24:06  20.9S  176.6W Mw=5.7  EMSC   FIJI REGION                  

O: 22OCT2020 08:24:06  20.9S  176.6W Mw=5.8  ANSS   FIJI REGION                  

P: 21OCT2020 128070    20.0S  176.0W 4.0-5.3 AAAAA  Tonga Islands              

 

 

An M 3.9-4.0 in Southern California today near Calipatria was reported by NEIC to have been felt with maximum intensity V in Calipatria and II-III in Niland, Brawley, and Palm Springs, California. NEIC reported aftershocks up to  M 2.9 in Southern California may have been felt with intensity II-III in the area(s) of  San Diego, California. This continues a series in southern California which began on September 30, 2020 and included an M 4.9 among others of M 4.0-4.5. A similar, but smaller series occurred on August 10, 2020. Forecast 127949 had expected renewed activity in this swarm around October 18. The largest event of M 4.0 occurred within about an hour of local solar noon and was likely promoted by high tidal stresses which maximize near this hour.

 

O: 22OCT2020 20:31:32  33.2N  116.0W ML=2.6  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 20:45:28  33.2N  115.6W ML=2.5  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 20:52:26  33.2N  115.6W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 20:53:38  33.2N  115.6W ML=2.1  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 20:59:26  33.2N  115.6W Mw=4.0  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 21:02:16  33.2N  115.6W ML=2.6  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 21:03:29  33.2N  115.6W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 21:07:39  33.2N  115.6W ML=2.5  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 21:22:03  33.2N  115.6W ML=2.8  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 21:36:28  33.2N  115.6W ML=2.2  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 21:37:56  33.2N  115.6W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 23OCT2020 06:32:09  33.2N  115.6W Ml=2.9  EMSC   SOUTHERN CALIFORNIA

O: 22OCT2020 20:56:46  33.1N  115.7W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 23OCT2020 06:34:16  33.2N  115.6W ML=2.2  EMSC   SOUTHERN CALIFORNIA          

P: 18OCT2020 127949    32.9N  115.6W 2.5-4.3 BAAAA  So. California             

 

 

 

Unusual earthquakes of M 4.4 and 4.6 also hit in the region near Resolute, Nunavit today. It was not reported felt in this remote area. The last earthquake within about 250 km of this epicenter with M>=4.4 was an M 5.2 on February 10, 2017 and prior to that an M 6.0 on January 8-9, 2017. These were the only such events in this area in the past 30 years.  Forecast 128035 had expected a moderate earthquake was possible in this region around October 18. This epicenter, like those in Iceland of recent days is at 103 degrees from the M 6.8 in Atacama Chile which occurred on September 1.

 

O: 22OCT2020 07:22:56  74.1N   91.0W mb=4.6  EMSC   DEVON ISLAND, NUNAVUT, CANADA

O: 22OCT2020 07:22:58  74.0N   90.9W MB=4.4  ECAN Resolute, NU                   

P: 18OCT2020 128035    65.0N   86.0W 2.5-3.9 BCAAA  Nunavit/Hudson Bay, Canada 

 

A light M 2.2 was also recorded in the area of New York today but not reported felt. The last earthquake with M>=2.2 within about 150 km of this epicenter was an M 2.2 on February 7, 2018, the last in this area of greater magnitude was an M 2.5 on July 5, 2014. Forecast 127982 had expected today's event within about 60 km of this epicenter was likely around October 16.

 

O: 22OCT2020 16:23:54  41.5N   73.8W mb=2.2  EMSC   NEW YORK                     

P: 16OCT2020 127982    41.0N   74.0W 2.0-3.9 CAAAA  New York State             

 

A series of earthquakes occurred today in the Reykjanes Ridge including events of M 5.1, 5.2 and 5.3.  These epicenters are near the sixth node (60 degrees) from the Alaska Peninsula event of M 7.5 of October 19, similar to the swarm in Iceland two days ago, and was probably promoted by the Iceland and Alaska events. Forecast 128016 had expected today's activity was likely within about 150  km of this epicenter around October 19. The mainshocks of M 5.2 and 5.3 within minutes of local solar midnight and was probably promoted by high tidal stresses which maximize near this hour. This activity is at the third node (120 degrees) from the M 6.8 in Sumatra of August 18 and at the seventh node (52 degrees) from  the central Mid-Atlantic M 6.8 of September 18 was probably promoted by energy from those sources.

 

O: 22OCT2020 12:00:48  52.7N   35.2W mb=4.7  EMSC   REYKJANES RIDGE

O: 22OCT2020 23:06:32  52.7N   35.0W Mw=5.1  EMSC   REYKJANES RIDGE

O: 22OCT2020 02:31:43  52.8N   35.0W MB=5.3  ECAN Northern Mid-Atlantic     

O: 22OCT2020 02:22:01  52.8N   35.0W MB=5.2  ECAN Northern Mid-Atlantic      

O: 22OCT2020 10:54:50  52.7N   34.8W mb=4.6  EMSC   REYKJANES RIDGE              

P: 19OCT2020 128016    53.0N   32.0W 4.0-5.3 BABAA  North Mid-Atlantic Ridge   

 

At the other end of the Atlantic a series of moderate earthquakes occurred in the South Shetland and Falkland Islands near South America. The activity in the South Shetland area follows similar activity which began in late September and has continued off-and-on since that time. The last earthquake of M>=4.4 in the Falkland Island area was an M 5.0 on September 7. Other earthquakes in the past year in the Falklands occurred on July 30 and July 8 (M 4.6-4.7). This epicenter is at the sixth node (60 degrees) from the Mid-Atlantic M 6.8 of September 18.

 

O: 22OCT2020 17:25:10  54.6S   57.0W mb=4.4  EMSC   FALKLAND ISLANDS REGION      

O: 22OCT2020 19:19:46  62.4S   58.3W Mw=5.1  EMSC   SOUTH SHETLAND ISLANDS

O: 22OCT2020 05:40:02  62.3S   58.1W mb=4.9  EMSC   SOUTH SHETLAND ISLANDS       

P: 14OCT2020 128092    61.0S   58.0W 4.0-5.4 CBAAA  Southern  Ocean            

 

A series of moderate earthquakes including an M 5.3 and 5.0 also occurred today in the Northern Mid-Atlantic Ocean. The M 5.0 occurred near local solar midnight and may have been promoted by high tidal stresses which maximize near this hour. Forecast 127887 had expected this activity in the Mid-Atlantic to the south was likely in mid-October. This activity is located at 144 degrees from the M 6.8 in Sumatra of August 18, 2020 and may have been promoted by energy from this source. A similar swarm at 144 degrees from Sumatra occurred in Oklahoma today.

 

O: 23OCT2020 02:19:07  19.9N   45.8W mb=5.0  EMSC   NORTHERN MID-ATLANTIC RIDGE

O: 23OCT2020 00:33:35  20.0N   45.9W Mw=5.3  EMSC   NORTHERN MID-ATLANTIC RIDGE

O: 22OCT2020 09:54:59  19.9N   45.8W mb=4.6  EMSC   NORTHERN MID-ATLANTIC RIDGE  

P: 14OCT2020 127887    17.0N   47.0W 4.0-5.3 CCAAA  Mid-Atlantic Ridge          

 

MODERATELY STRONG QUAKE SHAKES ANTOFAGASTA, CHILE

 

EARTHQUAKE SUMMARY FOR OCTOBER 21, 2020

 

The largest earthquake in the world today was an M 5.7 off the coast of Antofagasta, Chile. GUC reported this earthquake was felt with intensity   IV in  Atacama at Chanaral, Copiapo, Diego de Almagro and Tierra Amarilla and III in Caldera; in Antofagasta with IV in Taltal and in Tarapaca with III in Pica, Chile. It was probably promoted by energy from the Alaska Peninsula M 7.5 of October 19 as it occurred at 108 degrees from that epicenter in a zone where seismic energy concentrates and often triggers far-field activity following large events as noted in previous issues of this summary as:

 

"101-109 degrees: Alaska Peninsula to ... West Chile Rise, northern Chile, southern Peru" (October 19, 2020)

 

The last earthquake of M>=5.7 within about 200 km of this epicenter in Antofagasta, Chile was an M 6.1 on July 25, 2-16 about 100 km south of today's epicenter. An M 6.8 also hit Atacama, Chile on September 1, 2020 about 300 km southwest of today's epicenter. Forecast 128063 had expected today's event was likely in this area around October 17.

 

O: 21OCT2020 09:13:05  25.5S   71.0W Mw=5.7  EMSC   OFF COAST OF ANTOFAGASTA, CHIL

O: 21OCT2020 09:13     25.6S   70.8W mb=5.7  GUC    Atacama at Chanaral, Copiapo,

P: 17OCT2020 128063    24.0S   69.0W 4.0-5.4 BBBAA  Coast No. Chile            

 

A moderate sized earthquake of M 5.2 in the Ionian Sea was preceded about half a minute earlier by a foreshock of M 4.4 NEIC reported this earthquake of M 5.2 in the Ionian Sea, Greece  was felt with intensity II-III in the area(s) of  the Ionian Sea, Greece at Ayios Nikolaos, Kentriki, Ellada. This epicenter is at the fourth node (90 degrees) from the Alaska Peninsula M 7.5 of October 19 and was probably promoted by energy from that event.  It is also at 100 degrees from the M 6.8 in Atacama, Chile of September 1. The last earthquake in the Ionian Sea with M>=5.2 within about 200 km of this epicenter occurred on November 19, 2018 with M 5.2, an aftershock of an M 6.8 near the same epicenter on October 25, 2018. Today's event is also likely an aftershock of that event. Forecast 127936 had expected today's earthquake within about 50 km was likely around October 17.

 

O: 21OCT2020 23:00:17  37.2N   20.4E mb=4.4  EMSC   IONIAN SEA                   

O: 21OCT2020 23:00:54  37.2N   20.5E Mw=5.2  EMSC   IONIAN SEA                   

P: 17OCT2020 127936    37.0N   21.0E 3.0-4.3 AAAAA  No. Greece                 

 

A moderate M 4.7 west of the Volcano Islands, Japan today was probably enhanced by energy from Tropical Depression 20W which passed over this epicenter yesterday as noted in the previous issue of this summary:

 

"Tropical Depression 20W formed west of the Volcano Islands, Japan today with winds up to 40 kts. This system  may approach Honshu, Japan as a tropical storm in the next four days. Moderate  effects on regional seismicity are likely." (October 21, 2020)

 

The last earthquake with M>=4.7 within about 200 km of today's epicenter was an

M 4.8 one year ago on October 22, 2019 with M 4.8. Forecast 127901 had expected today's event was likely around October 21 to the north. This epicenter is at the seventh node (51.4 degrees) from the epicenter of the Alaska Peninsula quake of October 19 and was probably promoted by energy from that source.

 

O: 21OCT2020 15:20:02  25.6N  141.5E mb=4.7  EMSC   VOLCANO ISLANDS, JAPAN REGION

P: 21OCT2020 127901    28.0N  139.0E 4.0-5.3 ACBAA  Bonin Islands              

 

The strongest earthquake in the U.S. or Canada today was an M 4.7 in the Alaska Peninsula aftershock series.  A listing of events in the Alaska aftershock zone of M>=4.0 follows. A more complete list can be found in the "ALASKA" regional section of this report.

 

O: 21OCT2020 11:34:52  54.2N  159.8W mb=4.6  EMSC   SOUTH OF ALASKA

O: 22OCT2020 05:55:35  54.3N  159.6W mb=4.1  EMSC   SOUTH OF ALASKA

O: 21OCT2020 23:22:23  54.4N  159.9W Mw=4.1  EMSC   SOUTH OF ALASKA

O: 21OCT2020 11:56:41  54.5N  159.7W Mw=4.7  EMSC   SOUTH OF ALASKA

O: 21OCT2020 14:16:41  54.5N  159.6W ml=4.2  EMSC   SOUTH OF ALASKA

O: 21OCT2020 12:32:41  54.6N  159.7W mb=4.7  EMSC   SOUTH OF ALASKA

P: 17OCT2020 128007    54.8N  158.7W 3.5-4.8 BAAAA  Alaska Peninsula           

 

An unusual earthquake of M 4.4 also hit in the region near Resolute, Nunavit today. It was not reported felt in this remote area. The last earthquake within about 250 km of this epicenter with M>=4.4 was an M 5.2 on February 10, 2017 and prior to that an M 6.0 on January 8-9, 2017. These were the only such events in this area in the past 30 years.  Forecast 128035 had expected a moderate earthquake was possible in this region around October 18. This epicenter is at 103 degrees from the M 6.8 in Atacama Chile which occurred on September 1, like those of recent days in Iceland and Northwest Territories, Canada.

 

O: 22OCT2020 07:22:56  73.9N   91.5W MB=4.4  ECAN of Resolute, NU                

O: 22OCT2020 07:22:56  74.1N   91.0W MB=4.6  EMSC of Resolute, NU                

P: 18OCT2020 128035    65.0N   86.0W 2.5-3.9 BCBAA  Nunavit/Hudson Bay, Canada 

 

MODERATELY LARGE QUAKE SHAKES ICELAND

 

EARTHQUAKE SUMMARY FOR OCTOBER 20, 2020

 

An M 5.6 earthquake in Iceland today was accompanied by a series of lighter shocks. The mainshock was reported felt in southwestern Iceland with intensity V in Keflavik and IV in Harnarfjordur, Gardabaei, Alflanes, Kopavogur, Seltjarnarnes, Reykajik, Grundarhverfi and III in Mosfellsbaer, and Vogar. This earthquake occurred within minutes of local solar noon and was likely promoted by high tidal stresses of the new moon which maximize near this time. This is the strongest earthquake in southern Iceland within about 200 km of this epicenter since an M 6.3 more than 12 years ago on May 29, 2008. Other such events occurred in 1998 and 2000. It is likely that this was triggered by energy from the Alaska Peninsula quake of M 7.5 yesterday combined with high tidal stresses and by the geomagnetic storm of the past day. Forecast 128029 had expected today's event was likely in southern Iceland  around October 17. Iceland is located at the sixth node (60 degrees) from the activity in the Alaska Peninsula.  An earthquake of M 5.3 in the northern Mariana Islands today was also at this distance from the Alaska Peninsula.  It is also at 100 degrees from the M 6.8 in Atacama, Chile of September 1, 2020 and may have been promoted by energy from that source.

 

O: 20OCT2020 13:51:36  63.9N   22.3W ML=3.2  EMSC   ICELAND REGION

O: 20OCT2020 14:01:43  63.9N   22.1W ML=3.6  EMSC   ICELAND REGION

O: 20OCT2020 14:04:48  63.9N   22.1W ML=3.1  EMSC   ICELAND REGION

O: 20OCT2020 14:28:14  63.9N   22.2W ML=3.0  EMSC   ICELAND REGION

O: 20OCT2020 14:30:38  63.9N   22.2W ML=3.1  EMSC   ICELAND REGION

O: 20OCT2020 14:35:50  63.9N   22.2W ML=3.7  EMSC   ICELAND REGION

O: 20OCT2020 14:40:04  63.9N   22.0W ML=3.0  EMSC   ICELAND REGION

O: 20OCT2020 14:45:35  63.9N   22.2W ML=3.1  EMSC   ICELAND REGION

O: 20OCT2020 15:17:19  63.9N   22.0W ML=3.1  EMSC   ICELAND REGION

O: 20OCT2020 15:22:54  63.9N   22.2W ML=3.0  EMSC   ICELAND REGION

O: 20OCT2020 15:27:12  63.9N   22.3W ML=3.8  EMSC   ICELAND REGION

O: 20OCT2020 15:28:16  63.9N   22.3W ML=3.6  EMSC   ICELAND REGION

O: 20OCT2020 15:30:36  63.9N   22.3W ML=3.0  EMSC   ICELAND REGION

O: 20OCT2020 15:32:45  63.9N   22.3W ML=4.0  EMSC   ICELAND REGION

O: 20OCT2020 15:33:47  63.9N   22.2W ML=3.6  EMSC   ICELAND REGION

O: 20OCT2020 15:35:24  63.9N   22.2W ML=3.1  EMSC   ICELAND REGION

O: 20OCT2020 18:47:18  63.9N   22.0W ML=3.1  EMSC   ICELAND REGION

O: 21OCT2020 00:22:39  63.9N   22.0W ML=3.3  EMSC   ICELAND REGION

O: 21OCT2020 02:22:47  63.9N   22.1W ML=3.0  EMSC   ICELAND REGION

O: 21OCT2020 06:05:15  63.9N   22.3W ML=3.4  EMSC   ICELAND REGION

O: 21OCT2020 06:23:19  63.9N   22.3W ML=3.4  EMSC   ICELAND REGION

O: 20OCT2020 13:43:16  64.0N   22.1W Mw=5.5  EMSC   ICELAND REGION

O: 20OCT2020 17:22:45  64.0N   22.1W ML=3.0  EMSC   ICELAND REGION

O: 20OCT2020 14:20:34  64.8N   23.8W ML=3.1  EMSC   ICELAND REGION

O: 20OCT2020 13:49:22  63.9N   22.1W ML=3.0  EMSC   ICELAND REGION               

O: 20OCT2020 15:07:45  64.8N   21.3W ML=3.1  EMSC   ICELAND                      

P: 17OCT2020 128029    63.0N   26.0W 3.0-4.4 ABBAA  Iceland area               

 

 

Other moderate earthquakes at high latitudes today, apparently related to the

M 7.5 in Alaska occurred as aftershocks in Alaska and in the Queen Charlotte Island area of British Columbia (M 4.6) and in the South Shetland Islands (M 5.0). The largest earthquakes in the U.S. or Canada today were aftershocks south of Alaska. These included an M 5.0 felt with light intensity in the Chugiak, Alaska area.

 

An earthquake of M 4.8 in the Unimak Island region about 300 km west of the epicenter of the M 7.5 in the Alaska Peninsula occurred today. This is the strongest earthquake in the Unimak area since an M 5.6 on August 13, the only such event in the past year in the Unimak area.  A minor swarm occurred on July 29 and 30 in the area at the end of July, 2020. Today's event was probably a regional aftershock of the M 7.5 in the Alaska Peninsula yesterday. Forecast 12022 had expected today's activity in the  Unimak Island area was likely around October 18-22.

 

NEIC reported this earthquake of M 4.8 in the Unimak Islands was felt with intensity IV in the area(s) of the Unimak Islands at Unalaska, Alaska.

 

O: 21OCT2020 03:35:25  53.1N  164.6W Mw=4.8  EMSC   UNIMAK ISLAND REGION, ALASKA 

P: 18OCT2020 128022    54.2N  165.0W 3.5-4.8 BAAAA  Unimak Islands, Aleutians  

P: 22OCT2020 128022    54.5N  163.5W 3.5-4.8 ABAAA  Unimak Islands, Aleutians  

 

A listing of events in the Alaska aftershock zone of M>=4.0 follows. A more complete list can be found in the "ALASKA" regional section of this report.

 

O: 20OCT2020 08:06:44  54.2N  159.8W mb=4.4  EMSC   SOUTH OF ALASKA

O: 20OCT2020 13:36:02  54.3N  159.6W mb=4.0  EMSC   SOUTH OF ALASKA

O: 20OCT2020 07:37:00  54.4N  159.8W mb=4.7  EMSC   SOUTH OF ALASKA

O: 20OCT2020 08:16:36  54.4N  159.7W mb=4.0  EMSC   SOUTH OF ALASKA

O: 20OCT2020 12:32:12  54.4N  159.8W Mw=5.2  EMSC   SOUTH OF ALASKA

O: 21OCT2020 01:17:54  54.4N  159.6W Mw=5.1  EMSC   SOUTH OF ALASKA

O: 21OCT2020 06:37:35  54.4N  159.7W mb=4.9  EMSC   SOUTH OF ALASKA

O: 20OCT2020 22:42:35  54.5N  159.9W mb=4.2  EMSC   SOUTH OF ALASKA

O: 20OCT2020 08:18:42  54.6N  159.7W mb=4.8  EMSC   SOUTH OF ALASKA

O: 20OCT2020 21:38:53  54.6N  159.7W mb=4.9  EMSC   SOUTH OF ALASKA

O: 21OCT2020 00:33:51  54.6N  159.7W mb=4.0  EMSC   SOUTH OF ALASKA

O: 20OCT2020 08:37:13  54.7N  159.8W mb=5.0  EMSC   SOUTH OF ALASKA

O: 20OCT2020 23:57:58  54.7N  159.7W mb=4.0  EMSC   SOUTH OF ALASKA

P: 17OCT2020 128007    54.8N  158.7W 3.5-4.8 BAAAA  Alaska Peninsula           

 

The M 4.6 in the Queen Charlotte Islands area which followed the M 7.5 in the Alaska Peninsula yesterday appears to have been a real, triggered event. ECAN reported a number of associated quakes which suggest the event of M 4.6 was real. This is an excellent example of a true P- or S- phase triggered event. In the previous issue of this report it had been noted as:

 

"An earthquake in Queen Charlotte Island, Canada of M 4.6 was reported by Earthquakes Canada four minutes after the Alaska Peninsula M 7.5. It may be a ghost event created by misreading of an automatic earthquake algorithm or a real event triggered by energy from Alaska." (October 19-20, 2020)

 

The last earthquake of M 4.6 or greater within about 200 km of this epicenter occurred six years ago on September 27, 2014. Forecast 128010 had expected this activity was likely within about 100 km of this epicenter around October 14. This epicenter is at 16 degrees from the Alaska Peninsula event and the quake occurred as the P-wave from that epicenter passed through the region.

 

O: 19OCT2020 20:58:07  52.0N  133.3W MB=4.6  ECAN OF VILLAGE OF QUEEN CHARLOTTE, 

P: 14OCT2020 128010    52.0N  132.0W 3.0-4.9 BAAAA  British Colombia           

 

The strongest earthquake in the world today was an M 5.9 in the Tonga Islands. It occurred near local solar noon and was probably promoted by high tidal stresses which maximize near this hour. This epicenter is near the fifth node from the Alaska Peninsula (72 degrees) and was probably promoted by energy from that source. An M 6.4 occurred about 200 km southwest of this epicenter on October 1, 2020 but the last event of equal or greater magnitude within this area was an M 6.2 on November 2, 2013. Forecast 128056 had expected today's event within about 50 km of today's epicenter was likely around October 16.

 

O: 21OCT2020 00:22:34  19.3S  172.4W Mw=5.9  EMSC   TONGA REGION                 

O: 20OCT2020 18:57:54  19.4S  174.1W mb=5.0  EMSC   TONGA                        

P: 16OCT2020 128056    19.0S  173.0W 4.0-5.3 BAAAA  Tonga Islands              

 

 

 

 

MAJOR AFTERSHOCK HITS ALASKA PENINSULA AREA

 

EARTHQUAKE SUMMARY FOR OCTOBER 19, 2020

 

A major aftershock of M 7.5 in the area south of Alaska and west of the Alaska Peninsula near Unimak Island occurred today. It was reported strongly felt with damage intensity VIII at Sand Point, Perryville, Cold Bay and King Cove; V in Chignik Lagoon, Chignik, and IV in False Pass and Pilot Point and Akutan, Alaska. The tsunami from the M 7.5 was recorded by PTWC in Hilo Hawaii and Hanalei, Hawaii with height of 11 inches (28 cm); Sand Point,  and Chignik Bay Alaska (2.5 feet); PTWC reported two tsunami waves of about 1.3 meters (4 feet 3 inches) were also generated. A tsunami warning was issued but later downgraded by PTWC. Local communities issued evacuations to higher elevations. Many boats headed out to sea, the safest place during moderate tsunamis. Many were prepared for a strong aftershock of the M 7.8 in the area of July 22. This summary had expected a strong earthquake in the western U.S. at this time with the new moon as:

 

"Based on the history of large earthquakes around the world over the past four months, it is likely that a strong enhancement of seismicity will coincide with the upcoming new moon. This summary has noted this as:

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-13, 2020)

 

The earthquakes in question follow:

 

MO DA HR MN SE YEAR LAT    LONG  DEP MAG Location

 

09 18 21 43 58 2020   0.8  -26.7  30 6.7 Central Mid-Atlantic Ridge

09 01 04 09 30 2020 -28.0  -71.0  30 6.8 Atacama, Chile

08 21 04 09 52 2020  -6.7  123.5 643 6.9 Banda Sea

08 18 22 29 22 2020  -4.2  101.2  10 6.8 Sumatra

07 22 06 12 44 2020  55.1 -158.6  30 7.8 Alaska Peninsula

06 23 15 29 04 2020  16.1  -95.9  10 7.4 Oaxaca, Mexico

06 18 12 49 00 2020 -33.4 -177.5 100 7.4 Kermadec Islands

" (October 13, 2020)

 

and

 

"Regional seismicity in Central and southern California and western North America peaks around October 18-20 and exactly half a year earlier around April 18-20 and often includes a strong earthquake towards the end of October. This  appears to be related to strong hurricanes and nor'easters at this time of year making landfall on the eastern seaboard of the U.S. Another contributing  factor is very strong geomagnetic storms or solar flares such as occurred with the Loma Prieta earthquake in October 1989. There is no evidence that a strong oceanic storm making landfall nor of a major geomagnetic or solar event at this time, so at this time only a moderate enhancement in regional seismicity in the western U.S or Canada is expected, but this could change as time proceeds." (October 10, 2020)

 

Since that time a series of B- and C-class solar flares occurred beginning on October 15 and culminating in the largest solar flare since May 29, 2020. This summary noted this in the previous issue as:

 

"It may also have been affected by a C 3.5 solar flare which occurred earlier in the day and was the strongest such observed flare since late May, 2020." (October 18, 2020)

 

Flare #    START  MAX       END    CLASS     DATE    Flux (Jm-2)

#-------------------------------------------------------------------------------

 

6960       1457   1511      1516   C3.5      (October 16, 2020)   1.3E-03  

 

The last flare of larger size was:

 

 450       1041   1046      1050   C9.3      (May 29, 2020)   1.4E-03      

 

A new geomagnetic storm reached active disturbance today at high latitudes. This was most active in the several hours before the M 7.5 in Alaska. This summary noted today's activity at high latitudes in the geomagnetic field as:

 

"The geomagnetic field saw quiet conditions today. The AP level was 6.  High latitude geomagnetic field saw disturbed conditions with AP 14. This is the strongest disturbance in the high latitude geomagnetic field since October 1-2. It peaked with KP reaching 5 from 1200 - 1800 UT, the strongest KP since October 2. Strong disturbances in the geomagnetic field can help promote seismicity and may do so at high latitudes with this storm." (October 19, 2020)

 

Continuing far-field triggering of seismicity is considered likely from today's event. This summary has detailed moderate to large earthquakes at likely triggering distances from the M 7.8 on July 22 in previous issues as:

 

180 degrees (node 2): Alaska Peninsula to South of Africa, 

144 degrees (node 5): Alaska Peninsula to South Shetland Islands, South Georgia Islands, Mozambique, South Africa, 

120 degrees (node 3): Alaska Peninsula to Los Lagos, Chile,

101-104 degrees (node 7): Alaska Peninsula to Socotra, South of Sumatra, Owen Fracture Zone, Central Mid-Atlantic, Honduras, Sumatra, South Pacific, West Chile Rise, northern Chile, southern Peru, Java, Sumatra, South Island, New Zealand, New Guinea to Gulf of California, South of Africa, Utah, Wyoming, Idaho, Southern California,

90 degrees (node 4): Alaska Peninsula to Northern Peru, Banda Sea, Iran, Crete, Lebanon, Pakistan, Kermadec Islands, Canary Islands,

72 degrees (node 5): Alaska Peninsula to Dominican Republic, Galapagos, Mindanao, Philippines, Fiji, England, Samoa, Philippines, New Guinea to Fox Islands, Xizang, China,

60 degrees (node 6): Alaska Peninsula to Vera Cruz, Oaxaca, Mexico

52 degrees (node 7): Alaska Peninsula to Pennsylvania, Greenland Sea, Quebec, North Carolina, New York, Izu Islands, Japan, 

 

Further seismic enhancement is likely in these regions in coming days.

 

The only other earthquake within about 250 km of today's epicenter with M>=7.5 in the past 30 years was the M 7.8 on July 22, 2020. Today's epicenter is about 100 km southwest of the July mainshock. Today’s activity in the Alaska Peninsula had been expected in forecast 128007 most likely to occur around October 17. Following is a listing of events of  M>=5.0 in the area today. A more complete listing can be found in the regional "ALASKA" section below.

 

O: 19OCT2020 21:22:27  54.3N  159.6W mb=5.2  EMSC   SOUTH OF ALASKA

O: 19OCT2020 21:32:19  54.3N  159.8W Mw=5.5  EMSC   SOUTH OF ALASKA

O: 19OCT2020 21:45:27  54.3N  159.9W Mw=5.9  EMSC   SOUTH OF ALASKA

O: 19OCT2020 21:05:57  54.4N  159.6W mb=5.8  EMSC   SOUTH OF ALASKA

O: 20OCT2020 04:07:06  54.4N  159.7W Mw=5.6  EMSC   SOUTH OF ALASKA

O: 19OCT2020 20:54:40  54.7N  159.8W Mw=7.5  EMSC   SOUTH OF ALASKA

P: 17OCT2020 128007    54.8N  158.7W 3.5-4.8 AAAAA  Alaska Peninsula           

 

An earthquake in Queen Charlotte Island, Canada of M 4.6 was reported by Earthquakes Canada four minutes after the Alaska Peninsula M 7.5. It may be a ghost event created by misreading of an automatic earthquake algorithm or a real event triggered by energy from Alaska.

 

O: 19OCT2020 20:58:07  52.0N  133.3W MB=4.6  ECAN OF VILLAGE OF QUEEN CHARLOTTE, 

P: 14OCT2020 128010    52.0N  132.0W 3.0-4.9 BAAAA  British Colombia           

 

Similarly an M 3.8 in Iceland ten minutes after the Alaska Peninsula event recorded by EMSC may or may not have occurred. Forecast 128029 had expected activity in this area in mid-October. 

 

O: 19OCT2020 21:04:11  66.4N   17.3W ML=3.8  EMSC   ICELAND REGION               

P: 15OCT2020 128029    66.0N   16.0W 3.0-4.4 BAAAA  Iceland area                

 

An M 4.9 near the antipode of the Alaskan Peninsula occurred eight hours earlier in the area South of Africa. This area became active in early and mid-August with an M 4.7 on August 3 and an M 4.9 on August 17. When the earthquake on August 17 occurred this summary noted in this regard:

 

"An earthquake of M 4.9 occurred today south of Africa within several km of the exact antipode of the M 7.8 in the Alaska Peninsula of July 22, 2020. This continues a series of events in this region which have occurred with moderate to large magnitude since the Alaska Peninsula quake. The area was expected to see enhanced activity at this time due to antipodal energy focusing from Alaska. Today's event is the nearest of these event to the exact antipode (compare 54N 158W and 53S 26E)." (August 17, 2020)

 

Forecast 128088 had expected today's activity south of Africa was likely in mid-October.

 

O: 19OCT2020 12:20:55  52.9S   25.7E mb=4.9  EMSC   SOUTH OF AFRICA              

P: 16OCT2020 128088    51.0S   29.0E 4.0-5.6 BBBAA  Atlantic-Indian Ridge      

 

A moderate earthquake of M 4.6-5.0 was widely felt in the Dominican Republic today. It was reported by NEIC with maximum intensity IV in the Dominican Republic at Las Terrenas, Samana, Monte Plata, El Carril, and II-III in San Pedro, Santo Domingo, Otra Banda, El Llano and in Puerto Rico at San Sebastian.

No tsunami was reported with this earthquake. The last earthquake within about

100 km of this epicenter in the Dominican Republic with M>=4.6 was an M 4.6 on December 22, 2018. The last of larger magnitude was an M 5.2 on September 23, 2018. Forecast 127894 had expected today's event in this area was likely in mid-October. A series of smaller regional events over the past several weeks led to today's M 4.6. Today's epicenter is near the fifth node (72 degrees) from the Alaska Peninsula.

 

O: 19OCT2020 09:00:46  19.1N   69.7W mb=4.6  EMSC   DOMINICAN REPUBLIC           

P: 15OCT2020 127894    19.0N   71.0W 3.4-4.9 BAAAA  Puerto Rico                

 

Earthquakes of M 5.8 and 5.9  (BMG magnitudes) hit the area south of Sumatra today.  BMG reported they were felt with intensity IV-V in the area near Bengkulu, Mukumuku, Tuapejat, Muara Aman, Tais and others. This continues a series of earthquakes in this area over the past four days as noted in previous issues of this summary as:

 

"The M 5.3 south of Sumatra continued a swarm in the area which began with an M 5.4 on October 15, 2020. It is the second largest event in this swarm to date. It occurred near local solar midnight and may have affected by high tidal stresses with the new moon. Forecast 127869 had expected activity in this area south of Sumatra was likely around October 21." (October 17-19, 2020)

 

Forecast 127869 had expected this area would be active around October 21. The M 5.9 occurred within about half an hour of local solar noon, a time at which tidal stresses area maximized and was probably promoted by  these stresses. An M 6.9 hit about 200 km southeast of today's epicenter on August 18, 2020 with the new moon but the last earthquake within this radius of larger magnitude was an M 6.1 on February 2, 2019.

 

These epicenters are located at 99 degrees from the Alaska Peninsula and energy transfer between the two areas may have helped trigger some of this activity in Alaska and Sumatra.

 

O: 19OCT2020 07:31:30   3.3S  100.4E Mw=5.9  EMSC   KEP. MENTAWAI REGION, INDONESI

O: 19OCT2020 07:47:21   3.3S  100.4E Mw=5.5  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 19OCT2020 09:42:55   3.3S  100.4E mb=5.1  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 19OCT2020 08:14:04   3.4S  100.4E mb=4.8  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 20OCT2020 01:52:07   3.5S  100.3E ML=4.2  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 20OCT2020 00:41:38   4.0S   99.9E mb=4.5  EMSC   SOUTHWEST OF SUMATRA, INDONESIA

P: 21OCT2020 127869     2.0S   99.0E 4.0-5.3 AAAAA  So. of Sumatera            

 

Seismicity in California was also active today. The strongest activity in this area was in the Redwood Valley area of northern California where events of M 3.5 and 4.0 were recorded by NEIC.  NEIC reported these earthquakes of M 4.0 and 3.5 in  Northern California was felt with intensity II-III in the area(s) of  Redwood Valley, Potter Valley, Willits, Ukiah, Comptche, Fort Bragg, Mendocino, Albion and Lakeport.  NEIC reported this earthquake of M 2.9 in northern California  was felt with intensity II-III in the area(s) of  northern California in Redwood Valley, Potter Valley, Willits, Mendocino, Nice.  The last earthquake of M>=4 in the area was an M 4.2 on August 19, 2020 and today's activity appears to be aftershocks of that event. Forecast 127925 had expected today's event within about 10 km was likely in mid-October.

 

O: 20OCT2020 03:02:52  39.4N  123.3W Md=2.0  EMSC   NORTHERN CALIFORNIA

O: 20OCT2020 04:01:06  39.4N  123.2W Md=2.9  EMSC   NORTHERN CALIFORNIA

O: 20OCT2020 01:59:46  39.4N  123.3W ML=3.1  EMSC   NORTHERN CALIFORNIA          

O: 20OCT2020 01:59:46  39.4N  123.3W ML=3.5  ANSS   NORTHERN CALIFORNIA          

O: 20OCT2020 01:58:50  39.4N  123.3W ML=4.0  ANSS   NORTHERN CALIFORNIA          

P: 14OCT2020 127925    39.4N  123.3W 2.5-4.3 CAAAA  Central California         

P: 17OCT2020 127925    39.7N  123.7W 2.5-4.3 BAAAA  Central California         

 

STRONG QUAKE SHAKES SOUTHERN SUMATRA, INDONESIA

 

EARTHQUAKE SUMMARY FOR OCTOBER 18, 2020

 

Earthquakes of M 5.8 and 5.9  (BMG magnitudes) hit the area south of Sumatra today.  BMG reported they were felt with intensity IV-V in the area near Bengkulu, Mukumuku, Tuapejat, Muara Aman, Tais and others. This continues a series of earthquakes in this area over the past four days as noted in previous issues of this summary as:

 

"The M 5.3 south of Sumatra continued a swarm in the area which began with an M 5.4 on October 15, 2020. It is the second largest event in this swarm to date. It occurred near local solar midnight and may have affected by high tidal stresses with the new moon. Forecast 127869 had expected activity in this area south of Sumatra was likely around October 21." (October 17-18, 2020)

 

 

"A series of moderate earthquakes followed the largest earthquake in the world today - an M 5.4 in the Mentawai region south of Sumatra. It was not reported felt in the region. The last earthquake within about 200 km of this epicenter with M>=5.4 was an M 5.4-5.5 on August 15, 2020. These appear to be aftershocks of an M 6.8-6.9 on August 18, 2020. This event occurred on the new moon date of August 18. This summary had noted this at the time as:

 

"The new moon arrived near the time of today's Sumatra earthquakes. This summary had expected strong triggering from this tidal alignment in Indonesia" (August 18-19, October 15-16, 2020)

 

Forecast 127869 had expected this area would be active around October 21. The M 5.9 occurred within about half an hour of local solar noon, a time at which tidal stresses area maximized and was probably promoted by  these stresses. An M 6.9 hit about 200 km southeast of today's epicenter on August 18, 2020 with the new moon but the last earthquake within this radius of larger magnitude was an M 6.1 on February 2, 2019.

 

O: 19OCT2020 07:47:21   3.3S  100.4E Mw=5.5  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 18OCT2020 22:48:49   3.4S  100.3E mb=5.1  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 19OCT2020 07:31:30   3.3S  100.4E Mw=5.9  EMSC   KEP. MENTAWAI REGION, INDONESI

P: 21OCT2020 127869     2.0S   99.0E 4.0-5.3 ABBAA  So. of Sumatera            

 

The strongest earthquake in the U.S. or Canada today was an M 4.3-4.8 in the region near Wrigley, Northwest Territories, Canada. This continues activity in the area which has been discussed in the past several issues of this summary as:

 

"The strongest earthquake in the U.S. or Canada  today was an M 4.4 in the Northwest Territories of Canada. The only earthquake in the past six years within about 300 km of this epicenter with M>=4.4 was an M 4.7 on July 2, 2020. Prior to that earthquakes of M 4.4 and 4.5 occurred in March and July, 2014 in this area. The strongest earthquake in this area in the past 30 years was an M 5.6 on June 10, 1990.  Forecast 127772 had expected today's event was likely within about 50 km of this epicenter was likely around October 10." (October 15, 2020)

 

The last earthquake within about 200 km of this epicenter with M>=4.8 occurred as an M 5.3 on September 26, 2011. Forecast 128034 had expected today's activity was likely around October 22 within about 50 km of today's epicenter.

 

O: 18OCT2020 16:46:37  62.3N  124.4W mb=4.3  EMSC   NORTHWEST TERRITORIES, CANADA

O: 18OCT2020 16:46:38  62.1N  124.7W MB=4.8  ECAN OF WRIGLEY, NT                 

P: 22OCT2020 128034    62.1N  124.2W 2.5-3.8 AAAAA  Northwest Terr., Canada    

 

The region of California and the Gulf of California, Mexico saw elevated seismicity today. The strongest earthquake in the area was an M 4.6 in the Gulf of California. This earthquake was probably triggered by high tidal stresses. It occurred within about half an hour of local solar noon, a prime time for tidal stresses associated with the current new moon as noted in previous issues of this summary:

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-15, 2020)

 

The event in the Gulf of California is the strongest within about 200 km of

this epicenter in nearly two years - since an M 5.3 on January 31, 2019 and prior to that an M 5.5 on October 8, 2018. Forecast 127903 had expected today's event within about 50 km was likely around October 18. This epicenter is located at 144 degrees from the Sumatra quake of August 18, 2020 and was probably promoted by energy from that source.

 

O: 19OCT2020 06:25:24  24.4N  109.0W mb=4.6  EMSC   GULF OF CALIFORNIA           

P: 18OCT2020 127903    24.0N  109.0W 3.5-4.8 AAAAA  Gulf of California         

 

Two earthquakes of M 3.5 also occurred today in Southern California. These

were also probably promoted by high tidal stresses. Forecasts 127949 and 127951

had expected this activity was likely around October 16-19.

 

 

NEIC reported the earthquake of M 3.5 in  Baja California was felt with intensity II-III in the area(s) of  Baja California at Puebla, Tecolotes, Mexicali, San Luis and in California at Heber, Holtville, Calexico and El Centro.

 

O: 18OCT2020 19:04:15  32.4N  115.3W ML=3.0  EMSC   BAJA CALIFORNIA, MEXICO

O: 18OCT2020 10:31:33  32.5N  115.1W Mw=3.5  EMSC   BAJA CALIFORNIA, MEXICO

O: 18OCT2020 10:41:36  32.5N  115.2W ML=2.0  EMSC   BAJA CALIFORNIA, MEXICO

O: 18OCT2020 10:33:47  32.4N  115.2W Ml=3.0  EMSC   BAJA CALIFORNIA, MEXICO      

P: 16OCT2020 127949    32.4N  115.8W 2.5-4.3 AAAAA  So. California             

 

The earthquake east of Los Angeles, California near Lander is the strongest within about 100 km of that epicenter since an M 4.0 on February 7, 2019.

 

O: 19OCT2020 03:34:43  34.9N  116.3W Mw=3.5  EMSC   SOUTHERN CALIFORNIA           

P: 19OCT2020 127951    35.6N  118.4W 2.5-4.3 AABAA  So. California             

 

NEIC reported this earthquake of M 3.5 in Southern California was felt with intensity II-III in the area(s) of Southern California in Newberry Springs.

 

 

 

 

 

MODERATELY LARGE QUAKE IN SOUTHERN ECUADOR

 

EARTHQUAKE SUMMARY FOR OCTOBER 17, 2020

 

The strongest earthquake in the world today was an M 5.5 off the west coast of northern Peru and Ecuador. NEIC reported it was felt with maximum intensity IV in Piura, Peru at El Alto, Mancora and Talara and in Zorritos Tumbes, Peru.

It occurred near local solar midnight and may have been promoted by strong tidal stresses with the new moon as noted in previous issues of this summary:

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-15, 2020)

 

It may also have been affected by a C 3.5 solar flare which occurred earlier in the day and was the strongest such observed flare since late May, 2020. Northern Peru lies near the geomagnetic equator where effects of such flares are prominent.

 

The last earthquake in northern Peru within about 200 km of this epicenter with M>=5.5 was an M 5.5 on August 25, 2020 and prior to that an M 5.6 on June 5, 2017. Forecast 127856 had expected today's event in Ecuador was likely around October 16.

 

O: 18OCT2020 06:58:30   3.9S   81.8W Mw=5.5  EMSC   NEAR COAST OF NORTHERN PERU  

P: 16OCT2020 127856     1.0S   81.0W 4.0-5.3 ACAAA  Ecuador                    

 

Other moderately large earthquakes today hit the Pacific-Antarctic Ridge with M 5.4 and Sumatra (M 5.3). The event in the South Pacific is the largest on the Pacific-Antarctic Ridge within about 300 km of this epicenter since an M 5.8 on August 31, 2020 and prior to that an M 5.4 on October 7, 2018. This event is at 101 degrees from the M 6.8 in the central Atlantic of September 18, the largest earthquake in the world since that time and may have been promoted by energy from that source.

 

O: 17OCT2020 10:49:20  54.5S  133.0W Mw=5.4  EMSC   PACIFIC-ANTARCTIC RIDGE       

 

The M 5.3 south of Sumatra continued a swarm in the area which began with an M 5.4 on October 15, 2020. It is the second largest event in this swarm to date.

It occurred near local solar midnight and may have affected by high tidal stresses with the new moon. Forecast 127869 had expected activity in this area south of Sumatra was likely around October 21.

 

O: 17OCT2020 20:21:48   3.2S  100.3E ML=4.0  EMSC   KEP. MENTAWAI REGION, INDONESI

O: 17OCT2020 17:54:59   3.3S  100.4E mb=5.3  EMSC   KEP. MENTAWAI REGION, INDONESI

P: 21OCT2020 127869     2.0S   99.0E 4.0-5.3 BBBAA  So. of Sumatera            

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in the Kodiak region, Alaska. The last earthquake in the Kodiak area of M>=4.0 was an M 4.2 on September 21, 2020 but the last within about 100 km of today's epicenter was an M 5.1 on July 8, 2020. Forecast 128007 had expected today's activity was likely around October 18.

 

O: 17OCT2020 09:17:57  56.2N  154.5W Mw=4.1  EMSC   KODIAK ISLAND REGION, ALASKA 

P: 18OCT2020 128007    54.7N  156.9W 3.5-4.8 ABBAA  Alaska Peninsula           

 

A series of light earthquakes were recorded near Mt. Etna, Sicily, Italy today.

This may be an expansion of the volcanic eruption at Etna which began on October 7, 2020 and has included strong ash emissions. The strongest of today's earthquakes in Sicily occurred near local solar noon and may have been enhanced by high tidal stresses associated with the new moon. Forecast 127972 had expected today's activity was likely in mid-October. This activity is at 103 degrees from the M 6.8 in Atacama, Chile of September 1 and may have been affected by concentrated energy from that source.

 

O: 17OCT2020 08:40:53  37.8N   14.6E ML=2.0  EMSC   SICILY, ITALY

O: 17OCT2020 08:44:54  37.8N   14.6E ML=2.8  EMSC   SICILY, ITALY

O: 17OCT2020 08:44:54  37.8N   14.6E ML=2.8  EMSC   SICILY, ITALY

O: 17OCT2020 09:00:40  37.8N   14.6E ML=2.3  EMSC   SICILY, ITALY

O: 17OCT2020 10:31:09  37.8N   14.6E ML=2.2  EMSC   SICILY, ITALY

O: 17OCT2020 11:13:58  37.8N   14.6E ML=2.4  EMSC   SICILY, ITALY

O: 17OCT2020 11:48:24  37.8N   14.6E ML=2.8  EMSC   SICILY, ITALY

O: 17OCT2020 12:29:14  37.8N   14.6E ML=3.3  EMSC   SICILY, ITALY

O: 17OCT2020 13:07:43  37.8N   14.6E ML=2.2  EMSC   SICILY, ITALY

O: 17OCT2020 13:14:45  37.8N   14.6E ML=2.1  EMSC   SICILY, ITALY

O: 17OCT2020 13:27:34  37.8N   14.6E ML=2.1  EMSC   SICILY, ITALY

O: 17OCT2020 13:55:19  37.8N   14.6E ML=2.2  EMSC   SICILY, ITALY

O: 17OCT2020 15:06:46  37.8N   14.6E ML=2.2  EMSC   SICILY, ITALY

O: 17OCT2020 15:09:07  37.8N   14.6E ML=2.1  EMSC   SICILY, ITALY

O: 17OCT2020 15:59:11  37.8N   14.6E ML=2.7  EMSC   SICILY, ITALY

O: 17OCT2020 20:14:08  37.8N   14.6E ML=2.5  EMSC   SICILY, ITALY

O: 18OCT2020 02:41:14  37.8N   14.6E ML=2.2  EMSC   SICILY, ITALY

O: 18OCT2020 06:02:23  37.8N   14.7E ML=2.8  EMSC   SICILY, ITALY

O: 17OCT2020 12:11:24  37.9N   14.6E ML=2.9  EMSC   SICILY, ITALY

O: 17OCT2020 18:50:20  37.9N   14.7E ML=2.4  EMSC   SICILY, ITALY

O: 18OCT2020 02:15:54  37.9N   14.6E ML=2.9  EMSC   SICILY, ITALY

O: 18OCT2020 06:42:33  37.7N   15.0E ML=2.0  EMSC   SICILY, ITALY                

P: 15OCT2020 127972    40.0N   17.0E 3.0-4.9 BCBAA  Italy                      

 

MODERATE QUAKE SHAKES MINDORO, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR OCTOBER 16, 2020

 

The strongest earthquake in the world today was an M 5.3-5.4 in Mindoro, Philippines. NEIC reported it was felt with maximum intensity VI in Southern Tagalog at Malig and IV in Batangas and Tagaylay. Intensity II-III was felt in Southern Tagalog at Nasugbu, Taal, Lumil, Dasmariana, Binan, Imus and Magsaysay, Quezon. PHIVOLCS reported this earthquake was felt with intensity V in Looc and Lubang, Occidental Mindoro; IV in Abra de Ilog and Sablayan, Occidental Mindoro; Calapan City, Oriental Mindoro, Lian, Lemeryu and Tingloy, Batangas; Tagaytay City, Mendez, Amadeo and Alfonso, Cavite; III in Puerto Galera, Oriental Mindoro; Paluan, Rizal and Mamburao, Occidental Mindoro; San Pascual, Batangas; Binan and Cabuyao, Laguna; City of Manila; Muntinlupa City, Makati City; Quezon City; Pasig City; Cainta, Rizal; II in Soccoro, Pinamalayan, Bansud, Naujan, and San Teodoro, Oriental Mindoor; San Pascual, Batangas; Indang, Cavite; Marikina City; Malabon City, Meycauauan City, Bulacan; Floridablanca, Pampanga and I in Pola, Oriental Mindoro; Calintaan, Occidental Mindoro. This continues activation of the region of central Philippines which began earlier this week and has included moderate events in Panay, Mindanao, Samar and Mindoro. The event in Mindoro of October 4 was an M 5.6. This activity may be related to the passage of Tropical Storm Nangka which passed through this region several days ago as noted at the time:

 

"TS Nangka (TD 18W) continued today west of Samar, Philippines with winds up to 55 kts. It is expected to track to the west over the next several days reaching Vietnam around October 11. Seismicity in southeast Asia is expected to be enhanced by this storm at landfall." (October 12-15, 2020)

 

Forecast 127884 had expected today's event was likely within about 150 km of this epicenter around October 14. Today's event is at 144 degrees from the M 6.8 of September 18 in the Central Atlantic and was probably promoted by concentrated energy from that source.

 

O: 16OCT2020 20:06:27  13.7N  120.4E Mw=5.3  EMSC   MINDORO, PHILIPPINES         

P: 14OCT2020 127884    13.0N  122.0E 3.5-4.8 AABAA  Luzon, Philippines         

 

The largest earthquake in the U.S. or Canada today was an M 4.0-4.1 in the Queen Charlotte Islands region of Canada. It was reported lightly felt in the epicentral area. This earthquake may have been promoted by tidal stresses associated with the new moon today as described in previous issues of this summary:

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-15, 2020)

 

The last earthquake within about 100 km of this epicenter with M>=4 was an M 4.2 on August 19, 2020. The last of significantly larger magnitude was an M 5.2 on May 23, 2020. In both cases (as with today's event) these two earthquakes occurred on the date of the new moon suggesting tidal triggering in the region and had been noted as such in this summary, for example:

 

"The largest earthquake in the U.S or Canada today was an M 5.2 west of Vancouver Island, British Columbia, Canada. NEIC reported intensity II-III felt within about 500 km of the epicenter at Ucluelet, and Walnut Grove, British Columbia. This epicenter is at 103 degrees from the M 7.3 of May 5 in the Banda Sea and was probably promoted by energy from that source.

It was associated with the new moon today when tidal stresses were high and was probably enhanced by these tidal stresses" (May 23, 2020)

 

Forecast 128010 had expected today's event was likely within about 100 km around October 17. This epicenter is at 104 degrees from the M 6.8 on October 21, 2020 in the  Banda Sea and may have been affected by concentrated energy from that source.

 

O: 16OCT2020 13:56:33  51.0N  130.7W MB=4.1  ECAN Bella Bella, BC                 

O: 16OCT2020 13:56:33  51.1N  130.3W ML=4.0  EMSC   QUEEN CHARLOTTE ISLANDS REGION

P: 17OCT2020 128010    50.3N  130.2W 3.0-5.1 AAAAA  British Colombia           

 

 

MODERATE SWARM SOUTH OF SUMATRA

 

EARTHQUAKE SUMMARY FOR OCTOBER 15, 2020

 

A series of moderate earthquakes followed the largest earthquake in the world today - an M 5.4 in the Mentawai region south of Sumatra. It was not reported felt in the region. The last earthquake within about 200 km of this epicenter with M>=5.4 was an M 5.4-5.5 on August 15, 2020. These appear to be aftershocks of an M 6.8-6.9 on August 18, 2020. This event occurred on the new moon date of August 18. This summary had noted this at the time as:

 

"The new moon arrived near the time of today's Sumatra earthquakes. This summary had expected strong triggering from this tidal alignment in Indonesia" (August 18-19, 2020)

 

Forecast 127869 had expected today's event in this region  was likely in mid-October. Today's epicenter is located at 100 degrees from the M 7.8 in the Alaska Peninsula event of July 22 and at 147 degrees from the Atacama, Chile M 6.8 of September 1 and may have been promoted by concentrated energy from those sources.

 

O: 15OCT2020 10:34:10   3.3S  100.3E mb=4.9  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 15OCT2020 22:06:27   3.4S  100.2E mb=4.5  EMSC   KEP. MENTAWAI REGION, INDONESIA

O: 15OCT2020 09:41:17   3.2S  100.4E Mw=5.4  EMSC   KEP. MENTAWAI REGION, INDONESI

P: 21OCT2020 127869     2.0S   99.0E 4.0-5.3 CBBAA  So. of Sumatera            

 

A moderate earthquake of M 4.0-4.3 in the Strait of Gibraltar, Spain today was followed by an M 2.9 aftershock. NEIC reported this earthquake of M 4.3 in Spain was felt with intensity II-III in the area(s) of Spain at Cortes de al Frontera and Estebona, Malaga. This is the strongest earthquake within about 150 km of this epicenter in nearly a year. The last such event of M>=4 was an M 4.5 on October 25, 2019. Forecast 127932 had expected today's event within this region was likely around October 15. Today's earthquake occurred within about half an hour of local solar midnight and was likely promoted by strong tidal stresses associated with the new moon which arrives today as noted in previous issues of this summary as:

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-15, 2020)

 

This activity is at 104 degrees from the Sumatra earthquakes earlier in the day and may have been promoted by energy from that source.

 

O: 15OCT2020 10:58:19  36.6N    5.5W ML=2.9  EMSC   STRAIT OF GIBRALTAR          

O: 16OCT2020 00:58:51  36.7N    5.4W ML=4.0  EMSC   STRAIT OF GIBRALTAR          

O: 16OCT2020 00:58:51  36.7N    5.4W ML=4.3  ANSS   STRAIT OF GIBRALTAR          

P: 15OCT2020 127932    36.0N    4.0W 3.5-4.8 AAAAA  Morocco/Spain              

 

The largest earthquake in the U.S. or Canada today was an M 4.0-4.2 in Southern Alaska. NEIC reported it was felt with maximum intensity V in Alaska at Indian and IV in Fort Richardson and II-III in Eagle River, Anchorage, Girdwood, Elmendorf AFB. The only earthquake within about 150 km of this epicenter in the past year was an M 4.2 on June 18, 2020. The last of larger magnitude in this area was an M 5.2 on September 17, 2019. Forecast 128028 had expected today's event was likely around October 16.

 

O: 15OCT2020 16:05:15  61.2N  149.3W Mw=4.2  EMSC   SOUTHERN ALASKA              

P: 16OCT2020 128028    62.7N  149.3W 3.2-4.9 ABAAA  Central Alaska             

 

Earthquakes in Alabama and Oklahoma today may also have been promoted by strong tidal stresses. The event in Oklahoma of M 2.2 occurred within about 15 minutes of local solar noon while an M 2.5 in Alabama occurred near local solar midnight, prime times for maximum tidal effects on seismicity. Forecast 127707 had expected the event in Alabama was likely in mid-October within about 100 km of this epicenter. An M 2.9 last occurred near today's Alabama event on June 25, 2020 and April 24, 2019.

 

NEIC reported this earthquake of M 2.6 in Alabama  was felt with intensity II-III in the area(s) of  Alabama at Vernon, Crane Hill and Pelham; in Starkville, Mississippi, Knoxville, Tennessee and Haworth, Oklahoma.

 

O: 15OCT2020 07:51:00  33.7N   88.0W Md=2.5  EMSC   ALABAMA                       

P:  9OCT2020 127707    33.0N   87.0W 2.0-3.9 CAAAA  Southeast U.S.             

 

The event in Oklahoma was not unusual and had been expected in forecast 127957.

 

O: 15OCT2020 18:14:53  36.5N   97.2W ML=2.2  EMSC   OKLAHOMA                      

P: 17OCT2020 127957    37.0N   98.0W 2.0-3.8 AAAAA  Southern Plains            

 

 

 

 

 

 

 

 

 

 

QUIET SEISMIC CONDITIONS CONTINUE

 

EARTHQUAKE SUMMARY FOR OCTOBER 14, 2020

 

Global seismicity remained at quiet conditions today with the largest earthquake

recorded an M 5.0 in Central Chile. GUC reported this earthquake was felt with intensity III in  Coquimbo at La Serena and Paiguano and II in Rio Hurtado, Chile. NEIC reported this earthquake of M 4.9 in San Juan, Argentina  was felt with intensity II-III in the area(s) of  San Juan, Argentina at San Juan, Mendoza, Rio Tercero and Buenos Aires and in Santiago, Chile.  The M 4.5 was reported felt with intensity V in San Juan, Argentina. The last event of M>=5 within about 150 km of this epicenter was an M 5.1 on December 9, 2019. The last of larger magnitude was an M 5.6 on May 20, 2019. Forecast 128073 had expected today's event within about 100 km of this epicenter was likely around October 17. This epicenter is at 144 degrees from the M 6.8 in Sumatra of August 18, 2020 and was probably promoted by energy from that source.

 

O: 15OCT2020 02:20     31.5S   69.2W mb=5.0  GUC    Coquimbo at La Serena and Paig

P: 17OCT2020 128073    31.0S   70.0W 4.0-5.4 AAAAA  Central Chile              

 

O: 14OCT2020 23:18:26  31.8S   68.1W Mw=4.5  EMSC   SAN JUAN, ARGENTINA          

P: 17OCT2020 128073    31.0S   70.0W 4.0-5.4 BABAA  Central Chile              

 

The strongest earthquake in the U.S. or Canada  today was an M 4.4 in the Northwest Territories of Canada. The only earthquake in the past six years within about 300 km of this epicenter with M>=4.4 was an M 4.7 on July 2, 2020. Prior to that earthquakes of M 4.4 and 4.5 occurred in March and July, 2014 in this area. The strongest earthquake in this area in the past 30 years was an M 5.6 on June 10, 1990.  Forecast 127772 had expected today's event was likely within about 50 km of this epicenter was likely around October 10.

 

O: 14OCT2020 09:06:56  62.2N  124.4W mb=4.1  EMSC   NORTHWEST TERRITORIES, CANADA

O: 14OCT2020 09:06:58  62.2N  124.6W MB=4.3  ECAN Wrigley, NT                    

P: 10OCT2020 127772    62.1N  124.2W 2.5-3.9 AAAAA  Northwest Terr., Canada    

 

 

MODERATE QUAKE IN SOCOTRA REGION

 

EARTHQUAKE SUMMARY FOR OCTOBER 13, 2020

 

The strongest earthquake in the world today was an M 5.4 in the Socotra Region south of Iran. It was followed by an M 4.5 aftershock. It was not reported felt in this remote area. The last earthquake of M>=5.4 within about 300 km of this epicenter was an M 5.4 on March 3, 2008. An M 6.0 hit about 350 km south  of this epicenter on July 19, 2014, the strongest regional event since 1996. Forecast 127875 had expected today's event within about 150 km of this epicenter was likely around October 16. This epicenter at 56 East longitude is directly south of the M 5.0 in the Caspian Sea yesterday at 52 East longitude, the largest in that region since 2015. Today's earthquake may have been promoted by tidal effects associated with the upcoming new moon as it occurred near the longitude of maximum stress with that event as noted in the previous issue of this summary:

 

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-13, 2020)

 

Today's epicenter is at 104 degrees from the M 7.7 in the Alaska Peninsula

quake of July 22 and was probably promoted by concentrated energy from that event.

 

O: 13OCT2020 09:29:52  13.9N   56.9E mb=5.4  EMSC   SOCOTRA REGION               

O: 13OCT2020 09:03:01  14.0N   56.9E mb=4.5  EMSC   SOCOTRA REGION               

P: 16OCT2020 127875    15.0N   56.0E 3.5-4.8 BAAAA  Arabian Sea                

 

The strongest earthquake in the U.S. or Canada  today was an M 4.4 in the Northwest Territories of Canada. The only earthquake in the past six years within about 300 km of this epicenter with M>=4.4 was an M 4.7 on July 2, 2020. Prior to that earthquakes of M 4.4 and 4.5 occurred in March and July, 2014 in this area. The strongest earthquake in this area in the past 30 years was an M 5.6 on June 10, 1990.  Forecast 127772 had expected today's event was likely within about 50 km of this epicenter was likely around October 10.

 

O: 14OCT2020 09:07:00  62.3N  124.8W MB=4.4  ECAN OF WRIGLEY, NT                  

P: 10OCT2020 127772    62.1N  124.2W 2.5-3.9 BAAAA  Northwest Terr., Canada    

 

 

STRONG TIDAL SEISMICITY POSSIBLE WITH UPCOMING NEW MOON

 

EARTHQUAKE SUMMARY FOR OCTOBER 12, 2020

 

Based on the history of large earthquakes around the world over the past four months, it is likely that a strong enhancement of seismicity will coincide with the upcoming new moon. This summary has noted this as:

 

"The new moon will arrive on October 16, 2020 at 19:31 UT. Longitudes which are near 115 West and 65 East are at sub-solar and antisolar conditions and will experience the strongest tidal stresses at this time. In the west these include areas of California and western U.S. and Canada and the Gulf of California as well as areas of the southeast Pacific Rise including areas near Easter Island. In the east these include areas of Afghanistan, Iran, India and Pakistan and portions of the Southwest Indian Ocean. These areas are most likely to see tidally triggered strong seismic enhancement in the next week. Many areas are subject to tidal enhancement of seismicity and the coming week should see several strong to major earthquakes in the world. In the past four months six of the seven quakes of M>=6.7 have occurred within several days of the New moon. These included events in the mid-Atlantic; Banda Sea; Sumatra; Alaska Peninsula; Oaxaca, Mexico and the Kermadec Islands. Three of these occurred on the 21st-23rd of the month the other three occurred on the 18th of the month." (October 12-13, 2020)

 

The earthquakes in question follow:

 

MO DA HR MN SE YEAR LAT    LONG  DEP MAG Location

 

09 18 21 43 58 2020   0.8  -26.7  30 6.7 Central Mid-Atlantic Ridge

09 01 04 09 30 2020 -28.0  -71.0  30 6.8 Atacama, Chile

08 21 04 09 52 2020  -6.7  123.5 643 6.9 Banda Sea

08 18 22 29 22 2020  -4.2  101.2  10 6.8 Sumatra

07 22 06 12 44 2020  55.1 -158.6  30 7.8 Alaska Peninsula

06 23 15 29 04 2020  16.1  -95.9  10 7.4 Oaxaca, Mexico

06 18 12 49 00 2020 -33.4 -177.5 100 7.4 Kermadec Islands

 

Seismicity around the world continued at quiet levels again today as it approaches the likely new moon enhancement.

 

The strongest earthquake in the world today was an M 5.0 in the Caspian Sea off shore Turkmenistan. The last earthquake within about 200 km of this epicenter with M>=5.0 was an M 5.2 on March 22, 2015 and prior to that an M 5.5 on June 7, 2014. Forecasts 127722 and 127973 had expected today's activity between October 5 and 13 within about 100 km of today's epicenter.

 

O: 12OCT2020 11:47:20  39.6N   52.0E mb=5.0  EMSC   CASPIAN SEA, OFFSHR TURKMENIST

P:  5OCT2020 127722    40.0N   52.0E 4.0-5.3 CAAAA  Kazakhstan                 

P: 13OCT2020 127973    40.0N   54.0E 4.0-5.3 AABAA  Kazakhstan                 

 

Active conditions also continued in the area of Chiapas, Mexico and Guatemala where an M 5.5 occurred yesterday. The strongest event in the region today was  an M 4.9. In the previous issue of this summary, this activity had been addressed as:

 

"The strongest earthquake felt in the world today was an M 5.5 off the coast of

Chiapas, Mexico. Today's event was reported by NEIC felt in Chiapas at Cacahoatan and Tuxtla Gutierrez and in Santa Catarina Pinula, Guatemala. A similar earthquake of M 5.5 last hit the area of Chiapas, Mexico on May 24, 2020 and on April 24, 2020. The only strong earthquake in the Chiapas area in the past year was an M 6.3 about 100 km south of today's M 5.5 on November 20, 2019. Forecast 127630 had expected today's event was likely about 100 km north of the epicenter was likely around October 9. This activity is at 144 degrees from the Banda Sea earthquake of August 21, 2020 (M 6.9) and was probably promoted by energy from this source." (October 11-12, 2020)

 

NEIC reported this activity in Chiapas, Mexico  was felt with intensity II-III in the area(s) of Guatemala at San Marcos la Laguna and Atitlan, Solola.

 

O: 12OCT2020 10:17:57  14.6N   93.8W ML=4.0  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 12OCT2020 14:36:22  14.6N   93.7W ML=4.0  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 12OCT2020 21:28:51  14.6N   93.8W ML=4.2  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 12OCT2020 07:03:06  14.7N   93.7W Mw=4.9  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 12OCT2020 21:06:43  14.8N   93.7W mb=4.2  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 13OCT2020 00:31:22  14.9N   93.6W mb=4.0  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 12OCT2020 15:25:23  15.0N   93.3W ML=4.1  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 12OCT2020 09:22:00  15.1N   93.6W ML=4.0  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 12OCT2020 16:38:31  15.1N   93.1W mb=4.0  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 12OCT2020 21:03:11  14.5N   93.8W ML=4.1  EMSC   OFF COAST OF CHIAPAS, MEXICO 

O: 13OCT2020 00:12:40  15.1N   92.6W mb=4.3  EMSC   CHIAPAS, MEXICO              

P:  9OCT2020 127630    16.0N   93.0W 3.5-5.1 BAAAA  Chiapas, Mexico            

P: 13OCT2020 127877    14.0N   94.0W 3.5-5.0 AAAAA  Chiapas, Mexico            

 

A series of moderate earthquakes also occurred in the central Philippines today. These events of M 4.8 and 4.0 in Mindanao; M 4.5 in the northern Philippines and M 4.7 in Samar may have been promoted by the passage through the area of Tropical Storm Nangka. The effects of this storm on this region were expected in previous issues of this summary as:

 

 

"TD 17W (Nangka) formed today west of Samar, Indonesia with winds up to 35 kts. It is expected to track to the west over the next several days reaching Vietnam around October 11. Seismicity in southeast Asia is expected to be enhanced by this storm at landfall." (October 9-13, 2020)

 

NEIC reported this earthquake of M 4.8 in  Mindanao, Philippines was felt with intensity II-III in the area(s) of Mindanao, Philippines at Dagami, Eastern Visayas. PHIVOLCS reported it at M 5.0 and felt with intensity IV in General Luna, Burgos and Socorro, Surigao Del Norte; San Jose, Dinagat Islands; III in Surigao City, Dapa, Surigao Del Norte and II in Carrascal and Tubod, Surigao Del Sur; Loreto, Dinagat Islands. Forecast 127884 had expected this activity in mid-October.

 

O: 12OCT2020 19:21:38   9.8N  126.1E mb=4.8  EMSC   MINDANAO, PHILIPPINES        

O: 12OCT2020 21:07:56  10.0N  126.3E ML=4.0  EMSC   MINDANAO, PHILIPPINES        

P: 21OCT2020 127884    12.0N  122.0E 3.5-4.8 CBCAA  Luzon, Philippines         

 

NEIC reported the earthquake of M 4.7 in Samar, Philippines  was felt with intensity II-III in the area(s) of Samar, Philippines at Pawing, Eastern Visayas. PHIVOLCS reported it was felt with intensity IV in Hernani, Eastern Samar; III in Llorente, Eastern Samar and II in Catbalogan City; La Paz, Julita, Dagami, Tanauan, Dulag and Barugo, Leyte.

NEIC reported this earthquake of M 4.6 in Antofagasta, Chile was felt with intensity II-III in the area(s) of Antofagasta, Chile.

 

O: 13OCT2020 06:49:04  11.3N  125.6E mb=4.7  EMSC   SAMAR, PHILIPPINES           

P: 14OCT2020 127884    13.0N  122.0E 3.5-4.8 ABCAA  Luzon, Philippines         

 

O: 13OCT2020 04:35:58  19.9N  121.4E mb=4.5  EMSC   BABUYAN ISL REGION, PHILIPPINE

P: 17OCT2020 127913    21.0N  120.0E 4.0-5.4 BBBAA  Taiwan                     

 

The strongest earthquake in the U.S. or Canada today was an M 3.5-3.6 in the Alaska Peninsula. The last earthquake within about 100 km of this epicenter was an M 3.8 on September 8, 2020. Forecast 128022 had expected today's event was likely around October 15.

 

O: 13OCT2020 03:18:51  54.2N  162.4W ml=3.5  EMSC   ALASKA PENINSULA             

O: 13OCT2020 03:18:50  54.0N  162.3W ml=3.6  ANSS   ALASKA PENINSULA             

P: 15OCT2020 128022    54.5N  161.8W 3.5-4.8 AAAAA  Unimak Islands, Aleutians  

 

MODERATE QUAKES IN CHIAPAS, MEXICO AND CRETE, GREECE

 

EARTHQUAKE SUMMARY FOR OCTOBER 11, 2020

 

The strongest earthquake felt in the world today was an M 5.5 off the coast of

Chiapas, Mexico. Today's event was reported by NEIC felt in Chiapas at Cacahoatan and Tuxtla Gutierrez and in Santa Catarina Pinula, Guatemala. A similar earthquake of M 5.5 last hit the area of Chiapas, Mexico on May 24, 2020 and on April 24, 2020. The only strong earthquake in the Chiapas area in the past year was an M 6.3 about 100 km south of today's M 5.5 on November 20, 2019. Forecast 127630 had expected today's event was likely about 100 km north of the epicenter was likely around October 9. This activity is at 144 degrees from the Banda Sea earthquake of August 21, 2020 (M 6.9) and was probably promoted by energy from this source.

 

O: 12OCT2020 05:12:13  14.5N   93.8W ML=4.0  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 12OCT2020 05:53:20  14.5N   93.8W ML=4.2  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 12OCT2020 04:13:56  14.9N   93.6W Mw=5.5  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 11OCT2020 17:11:27  15.0N   94.0W ML=3.8  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 12OCT2020 04:17:42  15.1N   93.0W ML=4.2  EMSC   OFFSHORE CHIAPAS, MEXICO     

P:  9OCT2020 127630    16.0N   93.0W 3.5-5.1 BAAAA  Chiapas, Mexico            

 

A regional aftershock of M 5.1 also occurred about 200 km east of Chiapas in Guatemala today. NEIC reported this earthquake of M 5.1 in Guatemala  was felt with intensity II-III in the area(s) of Guatemala at San Nicolas (IV) and Coatepeque, and Almolonga, Quezaltenano, San Marcos la Laguna, Antigua Guatemala and San Lucas Sacatepequez, Guatemala City, Santa Catarina, and Chisec Alta,  Verapaz. The last earthquake of M>=5.1 was an M 5.3 on September 27 and prior to that an M 5.8 on August 4, 2020. Forecast 127634 had expected today's event was likely in Guatemala around October 8.

 

This activity in Mexico and Guatemala may have been promoted by stresses associated with Hurricane Delta which lingered to the north of these epicenters before hitting Louisiana today and yesterday. This summary had expected this effect in previous issues as:

 

"Hurricane DELTA continued today South of Texas with winds up to 105 kts. It is expected to track to the west and north slowly over the next several days. Low pressures associated with this storm will tend to unload the areas to the south and encourage seismicity in Central America   possibility of a large regional earthquake in the area while DELTA is in the area." (October 9-10, 2020)

 

O: 12OCT2020 06:06:57  14.7N   91.6W Mw=5.1  EMSC   GUATEMALA                    

P:  8OCT2020 127634    13.0N   91.0W 3.5-5.1 BBAAA  Guatemala                  

 

A series of moderate earthquakes occurred in Crete, Greece today. The largest

of these were of M 5.1 and 5.2.  NEIC reported this earthquake of M 5.2 in Crete, Greece was felt with intensity II-III in the area(s) of Crete, Greece at Palaikastron, Skhisma, Ierapetra, Limin, Kato Gouvai, Karpathos, Khanion, Nea Alikanassos. NEIC reported aftershocks of M 4.1-5.1 in Greece  were felt with intensity II-III in the area(s) of Greece at Kato Gouvai, Iraklion.  The last earthquake in Crete within about 100 km of today's swarm occurred as an M 5.4 on December 10, 2019. An M 5.9 event occurred about 150 km to the southwest of today's activity on September 18. Forecast 127669 had expected today's event within about 100 km was likely around October 11. This activity is at 103 degrees from the earthquake in Chiapas, Mexico and the Oaxaca quake of June 23, 2020 (M 7.4) and was likely promoted by energy from these sources.

 

O: 12OCT2020 00:30:40  35.6N   26.3E Mw=5.1  EMSC   CRETE, GREECE

O: 12OCT2020 00:44:26  35.6N   26.3E mb=4.2  EMSC   CRETE, GREECE

O: 12OCT2020 02:38:53  35.6N   26.3E ML=4.0  EMSC   CRETE, GREECE

O: 12OCT2020 04:11:27  35.6N   26.3E Mw=5.2  EMSC   CRETE, GREECE

O: 12OCT2020 05:00:33  35.6N   26.3E mb=4.1  EMSC   CRETE, GREECE

O: 12OCT2020 01:11:58  35.7N   26.3E ML=4.0  EMSC   CRETE, GREECE                

P: 11OCT2020 127669    35.0N   25.0E 3.0-4.6 AAAAA  Aegean Sea                 

 

The strongest earthquake in the world today was an M 5.7 aftershock in the Easter Island region of the South Pacific. The mainshock in this series occurred yesterday on October 10 and was discussed in the previous issue of this summary as:

 

"The earthquake (of M 5.9) in Easter Island region was also nearly antipodal to the complete solar eclipse of June 21 over Pakistan and India. Delayed effects may have enhanced today's events. The Easter Island event of M 5.9 was the strongest within about 250 km of this epicenter since an M 5.9 on June 18, 2018 and prior to that an M 5.9 on May 10, 2012. Forecasts 127799 and 127800 had expected today's event within the southeast Pacific Rise around October 8-10." (October 10-11, 2020)

 

NEIC reported this earthquake of M 5.7 in the Easter Island region was felt with intensity II-III in the area(s) of the Easter Island region at Hangaroa Osterinsel, Smaller Territories of Chile.

 

O: 11OCT2020 14:41:20  28.5S  112.1W Mw=5.7  EMSC   EASTER ISLAND REGION         

P:  8OCT2020 127799    24.0S  112.0W 4.0-5.3 BCAAA  So. East Pacific Rise      

P: 10OCT2020 127800    27.0S  107.0W 4.0-5.4 ABCAA  So. East Pacific Rise      

 

An M 5.1 also occurred today in the Izu Islands off southeastern Honshu, Japan.

This is the strongest earthquake in the Izu Islands within about 200 km of today's epicenter in more than a year - following an M 6.3 on June 4, 2019 and may be an aftershock of that event. It occurred as Typhoon Chan-Hom was passing over the epicenter and was probably triggered by stresses related to that storm as expected in earlier issues of this summary:

 

"Tropical Storm Chan-Hom continued east of the Kyushu, Japan today with winds up to 90 kts. It is expected to track to the north and east reaching southern Honshu as a Typhoon around October 10. It could help trigger a strong earthquake upon arrival in that area of Japan." (October 10, 2020)

 

Forecast 127654 had exected today's earthquake was likely in early October

within about 150 km of today's epicenter.

 

O: 12OCT2020 00:28:31  29.4N  139.4E Mw=5.1  EMSC   IZU ISLANDS, JAPAN REGION    

P:  5OCT2020 127654    28.0N  139.0E 4.0-5.3 CBAAA  Bonin Islands              

 

The strongest earthquake in the U.S. or Canada today was an M 4.0 in Southern Alaska near Anchorage. A similar event of M 4.1 occurred on October 7, 2020 and prior to that an M 4.0 on September 10, 2020. The only other such event within about 100 km of today's epicenter occurred December 16, 2019 with M 4.0. The last such event with significantly larger magnitude than M 4.0 was an M 5.0 on October 4, 2019. Forecast 127766 expected moderate regional seismicity was likely around October 9.

 

NEIC reported this earthquake of M 3.8-4.0 in Southern Alaska  was felt with intensity II-III in the area(s) of Southern Alaska at Willow, Wasilla, Elmendorf AFB, Anchorage, Talkeetna.

 

O: 11OCT2020 21:55:34  61.7N  150.5W Mw=4.0  EMSC   SOUTHERN ALASKA              

P:  9OCT2020 127766    60.1N  150.6W 3.2-4.9 ABAAA  Central Alaska              

 

 

ANTIPODAL QUAKES SOUTH OF AFRICA/FOX ISLANDS; EASTER ISLAND/INDIA, PAKISTAN

 

EARTHQUAKE SUMMARY FOR OCTOBER 10, 2020

 

Antipodal pairs of moderately strong to strong earthquake hit in the area of  Easter Island (M 5.9) and Manipur, India (M 5.4) and Pakistan today. A second antipodal pair was completed following the M 5.7 two days ago in the Fox Islands of Alaska with an M 5.4 southwest of Africa. Antipodal pairs are not uncommon in these regions and often follow strong geomagnetic storms. The earthquake in Easter Island region was also nearly antipodal to the complete solar eclipse of June 21 over Pakistan and India. Delayed effects may have enhanced today's events. The Easter Island event of M 5.9 was the strongest within aboutg 250 km of this epicenter since an M 5.9 on June 18, 2018 and prior to that an M 5.9 on May 10, 2012. Forecasts 127799 and 127800 had expected today's event withinthe southeast Pacific Rise around October 8-10.

 

O: 10OCT2020 13:14:57  28.7S  112.3W Mw=5.9  EMSC   EASTER ISLAND REGION         

P:  8OCT2020 127799    24.0S  112.0W 4.0-5.3 ACAAA  So. East Pacific Rise      

P: 10OCT2020 127800    27.0S  107.0W 4.0-5.4 ABCAA  So. East Pacific Rise      

 

A moderate M 5.4 quake shook portions of Manipur, India today. NEIC reported intensity V in Mayang Imphal, Manipur and Azawl, Mizoram and IV in Kohima Nagaland, in Assam at Maibong, Sichar, Mahur, and in Manipur, Kakching and Yairipok, Manipur, India. The last earthquake within about 250 km of this epicenter with M>=5.4 occurred with the solar eclipse on June 21, 2020 with M 5.6 about 200 km southwest of today's epicenter and prior to that as an M 5.5 on January 7, 2018. When the June, 2020 event occurred this summary noted:

 

 

"The earthquake in India/Myanmar today occurred near the sub-solar point at the time of the total eclipse. The sub-solar point is the point on the earth's surface where the sun is directly overhead at local solar noon. On the first day of summer in the northern hemisphere, the sun reaches its zenith at about 23 degree North latitude due to the tilt of the earth's axis. Vertical tidal triggering is therefore maximized near 23 North latitude at this time of year. Seismicity can be seen to increase at this latitude as well as evidenced by today's India earthquake at 23 North latitude; the Gujarat, India quake of M 5.5 on June 14; the M 5.5 in Taiwan of June 13 and a series in the southern Ryukyu Islands (M 5.0-5.6) over the past five days - all at 22-24 degrees north latitude. The only seismic areas at this latitude in the western hemisphere are in the Gulf California and the north mid-Atlantic Ridge." (June 22, 2020)

 

Forecast 127661 had expected activity in this area in early October.

 

O: 10OCT2020 17:38:00  24.6N   93.7E Mw=5.4  EMSC   MANIPUR, INDIA REGION        

P:  2OCT2020 127661    27.0N   88.0E 3.5-5.3 CCCAA  Nepal                      

 

An earthquake of M 4.1 also occurred much closer to the Easter Island quake antipode in the region of Pakistan (about 200 km from the antipode).  Forecast 127663 had expected this activity in Pakistan was likely around October 11.

 

O: 11OCT2020 06:02:55  30.4N   70.1E mb=4.1  EMSC   PAKISTAN                     

P: 11OCT2020 127663    29.0N   68.0E 3.5-4.8 ABBAA  Pakistan                   

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Gulf of Alaska. NEIC reported this earthquake of M 4.6 in the Gulf of Alaska  was felt with intensity II-III in the area(s) of the Gulf of Alaska at Homer. This is the strongest earthquake within about 150 km of this epicenter since an M 5.2 on June 28, 2000. The only other such event in this area in the past 30 years was an M 5.2 on December 15, 1994. Forecast 127766 had expected today's activity was likely in this area around October 9. This epicenter is at 103 degrees from the M 6.8 in Sumatra of August 18 and may have been enhanced by energy from that source.

 

O: 10OCT2020 11:22:09  58.5N  150.9W mb=4.8  EMSC   GULF OF ALASKA               

P:  9OCT2020 127766    60.1N  150.6W 3.2-4.9 ABAAA  Central Alaska              

 

An earthquake of M 4.6 occurred in the area southwest of Africa today. It was not felt in this remote area. This is the strongest earthquake in this area since an M 5.0  about 300 to the west of today's epicenter since an M 5.0 on September 4, 2020. The last such within 200 km of today's event occurred on February 11, 2020. This epicenter is near the antipode (about 200 km ) of the recent M 5.7 and 5.8 in the Fox Islands The activity of M 5.7 yesterday in the Fox Islands was described in the previous issue of this summary as:

 

 

"A moderately strong M 5.7 occurred in the Fox Islands, Aleutians today and was the strongest event in the U.S. or Canada today. NEIC reported it was felt with intensity III in Unalaska, Alaska. The last earthquake in the Fox Islands within about 200 km of today's epicenter with M>=5.8 was an M 5.8 on October 26, 2019  and before that an M 5.7 on August 25, 2018. The last event of M>=6 in the region was an M 6.9 on July 27, 2015." (October 10, 2020)

 

O: 10OCT2020 11:19:33  51.2S   17.6E mb=4.6  EMSC   SOUTHWEST OF AFRICA          

 

An unusual earthquake of M 3.9 shook areas of southern Sudan today. NEIC reported this earthquake of M 3.9 in Sudan  was felt with intensity II-III in the area(s) of Sudan at Juba. The last earthquake in Sudan within about 200 km of this epicenter with M>=3.9 was an M 4.4 on May 1, 2010 more than 10 years ago. An event of M 4.8 hit about 250 km southwest of this on January 5, 2019. This epicenter is at 103 degrees from the M 6.8 in Atacama, Chile which occurred September 1.

 

O: 10OCT2020 16:38:55   5.0N   32.1E mb=3.9  EMSC   SUDAN                        

 

 

CENTRAL VANUATU FEELS MODERATE QUAKE

 

EARTHQUAKE SUMMARY FOR OCTOBER  9, 2020

 

The strongest earthquake in the world on this quiet day in seismicity was an M 5.3 in Vanuatu. NEIC reported this earthquake of M 5.2-5.3 in Vanuatu  was felt with intensity II-III in the area(s) of Vanuatu at Vila Shefa. This continues elevated in this region which began with large events of M 6.2 on September 6 and 7, 2020. Forecast 127788 had expected today's activity within about 50 km was likely around October 5.

 

O:  9OCT2020 21:22:26  17.1S  167.5E Mw=5.3  EMSC   VANUATU                      

P:  5OCT2020 127788    17.0S  168.0E 4.0-5.3 BAAAA  Vanuatu Islands            

 

The only other earthquake in the world today of M>=5 was an M 5.0 in the  Mid-Ocean Ridge. It was not reported felt in this remote area. This epicenter is near the antipode of central California. Forecast 127820 had expected today's event was likely around October 4.

 

O: 10OCT2020 03:40:45  35.3S   53.8E Mw=5.0  EMSC   SOUTHWEST INDIAN RIDGE       

P:  4OCT2020 127820    34.0S   56.0E 4.0-5.3 CBBAA  So. Indian Ocean           

 

Seismic enhancement following the activity in the southwest Indian Ridge is likely in coming days. Regional seismicity in Central and southern California and western North America peaks around October 18-20 and exactly half a year earlier around April 18-20 and often includes a strong earthquake towards the end of October. This appears to be related to strong hurricanes and nor'easters at this time of year making landfall on the eastern seaboard of the U.S. Another contributing  factor is very strong geomagnetic storms or solar flares such as occurred with the Loma Prieta earthquake in October 1989. There is no evidence that a strong oceanic storm making landfall nor of a major geomagnetic or solar event at this time, so at this time only a moderate enhancement in regional seismicity in the western U.S or Canada is expected, but this could change as time proceeds.

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Fox Islands, Aleutians, Alaska. This continues the elevated seismicity in this area as previously described in this summary in the previous issue:

 

"A moderately strong M 5.7 occurred in the Fox Islands, Aleutians today and was the strongest event in the U.S. or Canada today. NEIC reported it was felt with intensity III in Unalaska, Alaska. The last earthquake in the Fox Islands within about 200 km of today's epicenter with M>=5.8 was an M 5.8 on October 26, 2019  and before that an M 5.7 on August 25, 2018. The last event of M>=6 in the region was an M 6.9 on July 27, 2015. Forecast 127753 had expected today's event within about 100 km of today's epicenter was likely around October 8." (October 8-9, 2020)

 

 

O: 10OCT2020 06:41:30  52.0N  169.7W mb=4.8  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P:  8OCT2020 127753    52.5N  169.2W 3.5-4.8 AAAAA  Fox Islands, Aleutians     

 

 

 

 

 

 

 

 

GEOMAGNETIC SEISMIC ENHANCEMENT CONTINUES AT HIGH AND LOW LATITUDES

 

EARTHQUAKE SUMMARY FOR OCTOBER  8, 2020

 

A series of large earthquakes occurred at high latitudes and near the geomagnetic equator today finishing up the geomagnetic effects from the strong geomagnetic storm of early October as noted in previous issues of this summary:

 

"The geomagnetic field saw major storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 15. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 30, 2020)

 

Today's activity included an M 6.3 in New Guinea on the geomagnetic equator; an M 5.7 in the Fox Islands, Alaska and moderate earthquakes at high latitudes in Jan Mayen near Norway (M 5.0) and the South Shetland Islands (M 4.9) and continuing unusual activity in the Caribbean and in New Britain (M 5.8).

 

The earthquake of M 5.0 in the Jan Mayen Island area today was the strongest earthquake in this area within about 200 km of today's epicenter since an M 5.2 on November 15, 2018. Both these events may be aftershocks of an M 6.7 which occurred November 9, 2018 the strongest in the region in the past 30 years, although a similar M 6.6-6.7 occurred on August 30, 2012. Forecast 127779 had expected today's event within about 100 km was likely around October 8.

 

O:  8OCT2020 10:42:20  71.7N   11.2W mb=5.0  EMSC   JAN MAYEN ISLAND REGION      

P:  8OCT2020 127779    71.0N   14.0W 3.5-4.8 AAAAA  Jan Mayen Isl. area        

 

O:  8OCT2020 09:02:20  62.3S   58.3W mb=4.9  EMSC   SOUTH SHETLAND ISLANDS       

P:  8OCT2020 127836    62.0S   58.0W 3.0-5.6 AAAAA  So. So. America            

 

An aftershock of M 5.1 occurred in the Papua New Guinea region in the eastern highlands at Kainantu and at Kundiawa, Sumbu. When the mainshock of M 6.3 occurred earlier in the day, this summary noted:

 

"The strongest earthquake in the world today was an M 6.3 in the region of Papua New Guinea. NEIC reported this event was felt with maximum intensity VI in Eastern Highlands, PNG at Kainantu, Madang; V in Lae, Morobe; IV in Goroka, Mount Hagen and II-III in Mendi, Southern Highlands and Port Moresby.

This event is at the antipode of the M 6.6 of September 6 in the Central Mid-Atlantic Ocean and was likely promoted by focused energy at the antipode of that event. A strong M 6.7 also hit the mid-Atlantic on September 18. The last earthquake within about 200 km of this epicenter with M>=6.3 was an M 7.2 on May 6, 2019 and prior to that an M 6.6 on November 7, 2014. Forecast 127616 had expected today's event was likely around October 4 in this area." (October 7-8, 2020)

 

 

O:  8OCT2020 23:14:35   6.2S  146.3E mb=5.1  EMSC   EASTERN NEW GUINEA REG., P.N.G

O: 08OCT2020 07:35:32   6.1S  146.2E Mw=6.3  EMSC   EASTERN NEW GUINEA REG., P.N.G.

P:  4OCT2020 127616     6.0S  148.0E 4.0-5.3 BABAA  New Ireland                

 

The M 5.8 in the New Britain area of PNG occurred about 200 km east of the M 6.3 earlier in the day in New Guinea. This is probably an aftershock of the M 6.2 about 100 km to the east which occurred on August 25, 2020. Forecast 127616 had expected today's event was likely around October 9 about 100 km south of today's epicenter.

 

O: 08OCT2020 15:58:52   5.9S  150.8E Mw=5.8  EMSC   NEW BRITAIN REGION, P.N.G.

O:  8OCT2020 10:31:54   5.3S  151.9E mb=4.9  EMSC   NEW BRITAIN REGION, P.N.G.   

P:  9OCT2020 127616     7.0S  151.0E 4.0-5.4 ABAAA  New Ireland                

 

Elevated seismicity continued in the eastern Caribbean today. An M 4.6 in the Leeward Islands was felt with intensity IV in Guadeloupe at Saint Martin and Saint-Bartelemy; in Saint Kitts and Nevis at Mansion Christ Church, Cayon, and in Princess Quarter, Netherlands Antilles, and Little Bay and Cul De Sac and II-III in Saint Kitts and Nevis at Monkey Hill, Sandy Point, Basseterre. 

 

An earthquake of M 4.5 also hit the Virgin Islands today. NEIC reported it was felt with intensity IV in Trujillo, Puerto Rico and in the Virgin Islands at Road Town, British Virgin Islands and in the U.S. Virgin Islands at Saint John, Frederiksted, Saint Thomas. An earthquake of M 3.9-4.0 also in the Virgin Islands today was reported by NEIC to have been felt with intensity II-III in Road Town, Tortola, British Virgin Islands and Bayamon, Puerto Rico. This continues regional activity which began yesterday with N M 5.2-5.3 in the Virgin Islands as described in the previous issue of this report:

 

"The strongest earthquake in the U.S., Canada or Possessions today was an M 5.2-5.3 in the U.S. Virgin Islands. NEIC reported it was felt with intensity II-III in the U.S. Virgin Islands at Saint John, Christianstedm, Saint Thomas Frederiksted, in the Netherlands Antilles at Low Lands, Simpson Bay, Cul De Sac, Little Bay and in Road Town British Virgin Islands. It was followed by an M 3.9 aftershock 13 minutes after the mainshock. This is the strongest earthquake in the Virgin Islands since an M>=5.2 was an M 5.2 on November 12, 2011, nine years ago but the last such event of larger magnitude near the Virgin Islands was an M 6.0-6.1 on October 11, 2008 twelve years ago. Forecast 127638 had expected today's event was likely within about 100 km of this epicenter around October 7. The largest earthquakes in this area generally occur during Hurricane Season with 15 of 18 event of M>=5.2 in the past 30 years occurring in the months of August through December and 14 of 18 in the months of October through December. Today's activity had been expected in this region with the occurrence of Hurricane Delta, still active in the Gulf of Mexico as:

 

 

"TS DELTA continued today between Honduras and Jamaica with winds up to 75 kts. It is expected to track to the west slowly over the next several days. Low pressures associated with this storm will tend to unload the areas to the south and encourage seismicity in Central America  and north in Jamaica and Cuba and possibly the Dominican Republic and Puerto Rico with the possibility of a large regional earthquake in the area while DELTA is in the area. It is expected to make landfall in Louisiana around October 10-11." (October 6, 2020)

 

Hurricane Teddy passed over the Virgin Islands in late September and probably

also promoted today's activity." (October 7-8, 2020)

 

The earthquake of M 4.6 in St. Martin, Leeward Islands is the strongest within about 150 km of this epicenter since an M 5.2 on December 24, 2017. Forecast 127637 expected this event within this area was likely around October 7.

 

O:  9OCT2020 04:14:03  17.8N   62.5W mb=4.6  EMSC   ST. MARTIN REGION, LEEWARD ISL

P:  7OCT2020 127637    17.0N   60.0W 3.0-4.9 AABAA  Leeward Islands            

 

The M 4.5 in the Virgin Islands is a regional aftershock of the M 5.3 of October 7, 2020. Forecast 127638 had expected this activity within about 100 kmwas likely around October 7.

 

O:  9OCT2020 01:21:25  18.0N   64.3W mb=4.5  EMSC   VIRGIN ISLANDS REGION        

O:  8OCT2020 09:06:24  18.1N   64.3W ML=4.0  EMSC   VIRGIN ISLANDS REGION        

P:  7OCT2020 127638    18.0N   65.0W 3.0-4.9 AAAAA  Leeward Islands             

 

A moderately strong M 5.7 occurred in the Fox Islands, Aleutians today and was the strongest event in the U.S. or Canada today. NEIC reported it was felt with intensity III in Unalaska, Alaska. The last earthquake in the Fox Islands within about 200 km of today's epicenter with M>=5.8 was an M 5.8 on October 26, 2019  and before that an M 5.7 on August 25, 2018. The last event of M>=6 in the region was an M 6.9 on July 27, 2015. Forecast 127753 had expected today's event within about 100 km of today's epicenter was likely around October 8.

 

O:  8OCT2020 14:22:41  53.0N  168.3W Mw=5.7  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P:  8OCT2020 127753    52.5N  169.2W 3.5-4.8 AAAAA  Fox Islands, Aleutians     

 

STRONG EARTHQUAKE IN NEW GUINEA ANTIPODAL TO MID-ATLANTIC

 

EARTHQUAKE SUMMARY FOR OCTOBER  7, 2020

 

The strongest earthquake in the world today was an M 6.3 in the region of Papua New Guinea. NEIC reported this event was felt with maximum intensity VI in Eastern Highlands, PNG at Kainantu, Madang; V in Lae, Morobe; IV in Goroka, Mount Hagen and II-III in Mendi, Southern Highlands and Port Moresby.

This event is at the antipode of the M 6.6 of September 6 in the Central Mid-Atlantic Ocean and was likely promoted by focused energy at the antipode of that event. A strong M 6.7 also hit the mid-Atlantic on September 18. The last earthquake within about 200 km of this epicenter with M>=6.3 was an M 7.2 on May 6, 2019 and prior to that an M 6.6 on November 7, 2014. Forecast 127616 had expected today's event was likely around October 4 in this

area.

 

O:  8OCT2020 07:35:32   6.1S  146.2E mw=6.3  ANSS   Kainantu Papua New Guinea    

P:  4OCT2020 127616     6.0S  148.0E 4.0-5.3 BABAA  New Ireland                

 

The strongest earthquake in the U.S., Canada or Possessions today was an M 5.2-5.3 in the U.S. Virgin Islands. NEIC reported it was felt with intensity II-III in teh U.S. Virgin Islands at Saint John, Christiansted, Saint Thomas Frederiksted, in the Netherlands Antilles at Low Lands, Simpson Bay, Cul De Sac, Little Bay and in Road Town British Virgin Islands. It was followed by an M 3.9 aftershock 13 minutes after the mainshock. This is the strongest earthquake in the Virgin Islands since an M>=5.2 was an M 5.2 on November 12, 2011, nine years ago but the last such event of larger magnitude near the Virgin Islands was an M 6.0-6.1 on October 11, 2008 twelve years ago. Forecast 127638 had expected today's event was likely within about 100 km of this epicenter around October 7. The largest earthquakes in this area generally occur during Hurricane Season with 15 of 18 event of M>=5.2 in the past 30 years occurring in the months of August through December and 14 of 18 in the months of October through December. Today's activity had been expected in this region with the occurrence of Hurricane Delta, still active in the Gulf of Mexico as:

 

 

"TS DELTA continued today between Honduras and Jamaica with winds up to 75 kts. It is expected to track to the west slowly over the next several days. Low pressures associated with this storm will tend to unload the areas to the south and encourage seismicity in Central America  and north in Jamaica and Cuba and possibly the Dominican Republic and Puerto Rico with the possibility of a large regional earthquake in the area while DELTA is in the area. It is expected to make landfall in Louisiana around October 10-11." (October 6, 2020)

 

Hurricane Teddy passed over the Virgin Islands in late September and probably also promoted today's activity.

 

One of the strongest earthquakes in the area of the Virgin Islands in the past century was an M 7.5 on October 8, 1974. The history section of this summary describes this as:

 

"10  8  9 50 58 1974  17.300  -62.000  47 7.5   Leeward Islands

 

Moderate earthquake in the Antilles at Antigua, Barbuda and St. Kitts.  Felt with maximum intensity VII. Four people were injured. Damage occurred to St. Johns Cathedral, government buildings, ports and refinerys. Roads were blocked by landslides and telephone lines, electric cables and water pipes were cut. At St. Kitts two churches were damaged. Felt from Puerto Rico to Guadeloupe." (October 7-8, 2020)

 

 

O:  7OCT2020 18:24:32  18.0N   64.3W Mw=5.2  EMSC   VIRGIN ISLANDS REGION        

O:  7OCT2020 18:24:34  18.2N   64.2W Mw=5.3  ANSS   VIRGIN ISLANDS REGION        

O:  7OCT2020 18:37:29  18.1N   64.2W ML=3.9  EMSC   VIRGIN ISLANDS REGION        

P:  7OCT2020 127638    18.0N   65.0W 3.0-4.9 AAAAA  Leeward Islands            

 

An M 4.6 also occurred in southern Alaska today. This is the strongest earthquake within about 150 km of this epicenter in more than a year - since an M 5.0 on October 4, 2019 and prior to that an M 5.2 on September 17, 2019. Forecast 127767 had expected today's event was likely around October 7 in this area.

 

 

O:  7OCT2020 08:59:29  61.7N  151.1W mb=4.6  EMSC   SOUTHERN ALASKA              

P:  7OCT2020 127767    62.8N  151.2W 3.2-4.8 ABAAA  Central Alaska             

 

 

STRONG EARTHQUAKE SHAKES FIJI

 

EARTHQUAKE SUMMARY FOR OCTOBER  6, 2020

 

The strongest earthquake in the world today was an M 6.0 in the region of Tonga and Fiji. The last earthquake with M>=6 within about 200 km of this epicenter in Fiji was an M 6.2 on March 10, 2019 and rior to that an M 6.8 on November 18, 2018. These are probably aftershocks of an M 8.2 which shook the region on August 19, 2018. Forecast 127786 had expected today's event was likely within about 50 km of this epicenter around October 4. This is near the geomagnetic equator and may have been promoted by effects from the strong geomagnetic storm of the beginning of October. Activity near the equator is likely to continued enhanced for several more days.

 

O:  6OCT2020 10:11:45  18.1S  178.4W Mw=6.0  EMSC   FIJI REGION                  

P:  4OCT2020 127786    18.0S  178.0W 4.0-5.3 AAAAA  Tonga Islands              

 

The largest earthquake in the U.S. or Canada today was an M 4.9 in the Andreanof Islands, Alaska area. An M 4.7 hit the same area on October 4, 2020 but the last earthquake of larger magnitude in the Andreanof Islands was an M 5.3 on July 15, 2020. Forecast 127749 had expected today's event within about 100 km of the epicenter was likely around October 8.

 

O:  7OCT2020 01:34:15  51.4N  178.4W mb=4.9  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  8OCT2020 127749    51.3N  176.8W 3.5-4.8 AAAAA  Andreanoff Isls, Aleutians 

 

A series of unusual earthquakes occurred in eastern Canada today. The largest of these was an M 3.8 near Coral Harbour, Nunavit but a series of light earthquakes of M 2.2, 2.1, 2.0 and 1.8 was also lightly felt in the area near Sturgeon Falls, Ontario. The event in Nunavit of M 3.8 was the largest recorded in that region within about 200 km of this epicenter since an M 4.2 on March 10, 2012 and prior to that an M 3.8 on April 27, 2008. Forecast 127773 had expected this event within about 100 km was likely around October 11.

 

 

O:  6OCT2020 04:55:54  64.8N   86.4W MB=3.8  ECAN Coral Harbour, NU              

P: 11OCT2020 127773    64.0N   87.0W 2.5-3.8 BAAAA  Nunavit/Hudson Bay, Canada 

 

The last earthquakes of M>=2.2 within about 100 km of the Ontario events occurred on M 3.1 on February 8, 2019 and an M 2.2 on February 2, 2019 and prior to that an M 3.1 on September 30, 2015.  Forecast 127737 had expected today's event was likely within about 50 km of this epicenter around October 7.

 

O: 07OCT2020 02:15:21  46.1N   80.5W MB=2.0  ECAN Sturgeon Falls, ON   

O: 07OCT2020 02:11:51  46.1N   80.5W MB=2.1  ECAN Sturgeon Falls, ON. Felt  

O: 07OCT2020 00:46:14  46.1N   80.5W MB=1.8  ECAN Sturgeon Falls, ON   

O:  6OCT2020 04:30:22  46.1N   80.5W MB=2.2  ECAN Sturgeon Falls, ON             

P:  7OCT2020 127737    46.0N   81.0W 2.0-3.9 AAAAA  Ohio/Lake Erie             

 

STRONG AFTERSHOCK IN ALASKA PENINSULA

 

EARTHQUAKE SUMMARY FOR OCTOBER  5, 2020

 

The strongest earthquake in the world today was an M 5.9 in the Alaska Peninsula. NEIC reported it was felt with intensity III in Alaska at Sand Point and King Cove. This is an aftershock of the M 7.8 in the Alaska Peninsula of July 22, 2020. This is the strongest aftershock of that event since an M 6.1 four minutes after the mainshock on July 22, 2020. Other earthquakes within about 250 km of today's epicenter during the past 30 years occurred on July 18, 2108 (M 6.0); February 2, 2011 (M 5.9); May 26, 1993 (M 6.2) and May 13, 1993 (M 6.9). Today's activity at high latitudes appears to be related to the strong geomagnetic storm of the beginning of October as previous described in this summary:

 

"The geomagnetic field saw major storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 15. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 30, 2020)

 

O:  6OCT2020 05:54:50  54.9N  159.9W Mw=5.9  EMSC   SOUTH OF ALASKA              

P:  4OCT2020 127747    55.0N  158.9W 3.5-4.9 AAAAA  Alaska Peninsula           

P:  8OCT2020 127762    54.6N  161.7W 3.5-4.8 AAAAA  Unimak Islands, Aleutians  

 

Other moderate earthquakes at high latitude today included an M 5.2 in the Shetland Islands and the Pacific-Antarctic Ridge in the southern Pacific.  This event is the strongest within about 250 km of the epicenter in the Pacific-Antarctic Ridge since an M 5.8 on August 31, 2020. Other such events have occurred this year on July 7 (M 5.2) and April 1, 2020 (M 5.4).

 

O:  5OCT2020 08:48:10  54.5S  133.1W mb=5.2  EMSC   PACIFIC-ANTARCTIC RIDGE      

 

The M 5.2 in the South Shetland Islands today continued to elevated seismicity in that area. When a similar event occurred October 2, this summary noted:

 

 

"The strongest earthquake in the world today was an M 5.8 in the South Shetland Islands. It was not reported felt in this area. This is the largest earthquake in the current swarm which began about a month ago with and M 5.0 on August 29 and most recently an M 4.9 and 4.8 on September 29 and 30. Forecast 127836 had expected today's activity within about 50 km of this epicenter was likely around October 8. This continues the strong activation at high latitudes" (October 3-4, 2020)

 

Forecast 127836 had expected today's event within about 50 km of today's epicenter was likely around October 8.

 

O:  5OCT2020 19:01:27  62.3S   58.4W Mw=5.2  EMSC   SOUTH SHETLAND ISLANDS       

P:  8OCT2020 127836    62.0S   58.0W 3.0-5.6 BAAAA  So. So. America            

 

A series of moderate earthquakes also occurred today in the area of British Columbia.

 These were not reported felt and included events of M 4.1, 3.4, 3.4 and 3.3. An earthquake of M 5.4 hit about 150 km north of this on July 22, and accompanied the M 7.8 in the Alaska Peninsula of the same date. The only earthquake within about 100 km of today's epicenter of M>4.1 occurred three years ago on October 11, 2017. Forecast 127744 had expected today's activity was likely around October 6.

 

O: 05OCT2020 12:06:55  47.6N  129.1W MB=3.3  ECAN Tofino, BC    

O: 05OCT2020 11:34:50  47.6N  129.1W MB=3.4  ECAN Tofino, BC    

O: 05OCT2020 10:47:31  47.5N  129.0W MB=4.1  ECAN Tofino, BC    

O:  5OCT2020 12:07:58  47.6N  129.1W MB=3.4  ECAN Tofino, BC                     

P:  6OCT2020 127744    48.9N  129.3W 2.8-4.9 ABAAA  Vancouver Island area      

 

MODERATE QUAKE SHAKES MINDORO,  PHILIPPINES

 

EARTHQUAKE SUMMARY FOR OCTOBER  4, 2020

 

The strongest earthquake of the day was an M 5.6 in Mindoro, Philippines. NECI reported maximum intensity VI in Southern Tagalog, Philippines at Abra de Ilog; V in Payapa, and Tagaytay; IV in Luksuhin, Calantas, and San Pascual and II-III in Balatero, Mulawin, Silang, and San Vicente. PHIVOLCS reported intensity IV in Looc, Lubang, Mamburao, Paluan, Abra de Ilog and Sablayan, Occidental Mindoro; Calapan City, San Teodoro and Baco Oriental Mindoro and Tingloy and Calatagan, Batangas; III in Tagaytay City, Alfonso, Cavite; Pinamalaya, Oriental Mindor; San Pascual, Bauan, Mabini, Padre Garcia dnd Alitagtag, Batangas; II in Amadeo and Mendez, Cavite; Bansud, Socorro and Victoria, Oriental Mindoro; Calintaan and Magsaysay, Occidental Mindoro; Makati City; Quezon City, Mandaluyong City, Malabon City, Muntinlupa City; Pasig City; Taguig City, Binan, Laguna and I in Tanauan, Batangs; Mariveles, Bataan.This continues activation in the Philippines  which in the past five days has included moderate quakes in Mindanao, Luzon, Mindoro, and the Babyuan Island area of northern Philippines. This activation may have been promoted by the strong geomagnetic storm of early October as noted in previous issues of this summary. Forecast 127639 had expected today's activity was likely within about 50 km around October 2. This epicenter is at 144 degrees from the M 6.8 in the Central Atlantic of September 18, 2020 and may have been promoted by strong seismic energy concentration from that source.

 

O:  4OCT2020 18:16:55  13.6N  120.8E Mw=5.6  EMSC   MINDORO, PHILIPPINES         

P:  2OCT2020 127639    14.0N  121.0E 3.5-4.8 AAAAA  Luzon, Philippines         

 

The largest earthquake in the U.S. or Canada today was an M 4.8 in the Andreanof Islands, Aleutians, Alaska. It was not reported felt in this remote area. This earthquake is the strongest in the western Andreanof Islands since an M 4.9 on July 22, 2020 and prior to that an M 5.2 and 5.1 on June 19, 2020 Forecasts 127509 and 127749 had expected today's activity was likely a the end of September or early October.

 

O:  4OCT2020 07:11:43  51.2N  179.3W mb=4.8  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  2OCT2020 127749    51.6N  177.6W 3.5-4.8 AAAAA  Andreanoff Isls, Aleutians 

P: 30SEP2020 127509    51.6N  180.0W 3.5-4.9 BAAAA  Andreanoff Isls, Aleutians 

 

The strongest earthquake in California today was an M 3.1-3.4 in the Mammoth Lakes area near the Nevada border. NEIC reported this earthquake of M 3.4 in Mammoth Lakes, California  was felt with intensity II-III in the area(s) of Mammoth Lakes, California at Mammoth Lakes and Bishop. This is the strongest earthquake in the Mammoth Lakes area since an M 3.4 on July 2, 2020. The last event of larger magnitude in the Mammoth Lakes, California area was an M 4.1 on April 5, 2020. It was accompanied by events of M 2.1 and 2.0. Forecast 127673 had expected today's M 3.4 was likely within about 20 km around October 6.

 

O:  4OCT2020 16:28:52  37.6N  118.6W Md=2.1  EMSC   CENTRAL CALIFORNIA           

O: 05OCT2020 04:06:36  37.5N  118.8W ML=3.1  EMSC   CENTRAL CALIFORNIA

O: 05OCT2020 04:06:36  37.5N  118.8W ML=3.4  ANSS   CENTRAL CALIFORNIA

O: 05OCT2020 00:24:23  37.5N  118.8W Md=2.0  EMSC   CENTRAL CALIFORNIA

P:  6OCT2020 127673    37.5N  118.6W 2.5-4.3 AAAAA  California/Nevada area     

 

 

 

 

 

 

UNUSUAL M 5.3 IN EASTERN GREENLAND

 

EARTHQUAKE SUMMARY FOR OCTOBER  3, 2020

 

An unusual earthquake of M 5.3 hit the region of eastern Greenland today but was not reported felt. This is the largest earthquake within about 500 km of this epicenter in at least 30 years and may have been promoted by melting of the Greenland Ice sheet and subsequent unloading of the area. The current geomagnetic storm, the strongest at high latitudes in nearly a year may also have helped promote today's event in Eastern Greenland. This epicenter is at 102 degrees from the M 6.8 in Atacama, Chile of September 1. Seismic energy from strong events concentrates at this distance following those events and often triggers additional seismicity at this distance. An unusual earthquake of M 3.9 east of Australia today was also at 103 degrees from the Atacama, Chile quake.

 

O:  3OCT2020 13:22:47  69.3N   30.0W Mw=5.3  EMSC   EASTERN GREENLAND            

 

The strongest earthquake in the world today was an M 5.5-5.9 in the Izu Islands south of Honshu, Japan. NEIC reported it was felt with maximum intensity IV in Yokosuka, Kanagawa and II-III in Tokyo and Gunma Prefectures. This may have been promoted from energy associated with  a new tropical storm near the Volcano Islands and with TD Kujira which passed east of this epicenter three days ago as noted in previous issues of this summary:

 

"TD Kujira formed today east of the Volcano Islands, Japan with winds up to 40 kts. It is expected track to the north into the north Pacific and not to threaten seismicity or landfall in this area." (September 27-28, 2020)

 

The last earthquake within about 200 km of today's epicenter with M>=5.9 was an

M 6.0 on November 9, 2017. Forecast 127696 had expected today's event within about 50 km was likely around October 6. This epicenter is at 144 degrees from the M 6.8 in the Atlantic Ocean of September 18 and was probably promoted by energy from that source. An M 4.7 in Luzon, Philippines also occurred at this distance from the Atlantic event today as did events in the Ryukyu Islands, Japan of M 4.8 and 5.1.

 

O:  3OCT2020 09:31:34  33.5N  141.0E Mw=5.9  EMSC   IZU ISLANDS, JAPAN REGION    

P:  6OCT2020 127696    34.0N  141.0E 4.0-5.3 BAAAA  Off East Coast Honshu      

 

 

The region of New Britain also continued with enhanced seismicity today. An M 5.7 was recorded about 300 km west of the similar event yesterday The last earthquake in New Britain within about 200 km of today's epicenter with M>=5.7 was recorded on October 31, 2010, ten years ago. Nearly all events of M>=5.7 in the area have occurred at least 100 km north of today's epicenter. The only exceptions in the past 30 years were an M 6.2 about 200 km west of today's event on January 3, 1991 and an M 5.8 on July 24, 1992 near today's epicenter.  Forecast 127616 had expected today's event was likely in early October within about 100 km of this epicenter. This epicenter is near the geomagnetic equator and was probably promoted by geomagnetic effects associated with the current geomagnetic storm

 

"The geomagnetic field saw major storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 15. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 30, 2020)

 

O:  3OCT2020 16:30:09   7.2S  150.0E mb=5.7  EMSC   NEW BRITAIN REGION, P.N.G.   

P:  9OCT2020 127616     7.0S  151.0E 4.0-5.4 CAAAA  New Ireland                

 

The strongest earthquake in the U.S. or Canada today was an M 4.4-4.5 in southwestern Utah. NEIC reported it was felt in Utah with intensity II-III in Paragonah, Antimony, Beaver, Greenville, Panguitch, Kingston, Marsvale, Parowan, Bryce Canyon and Brian Head. NEIC reported an aftershock of M 2.6 in Utah was felt with intensity II-III in the area(s) of Utah at Panguitch (VI), Bryce Canyon, Cedar City, Kanab, Page and Clearfield. This is the largest earthquake in Utah within about 100 km of this epicenter since an M 4.6-4.7 on January 3, 2011. Other such quakes in the past 30 years occurred with M 4.5 on January 2, 1998 and July 19, 2001. Forecast 127711 had expected today's activity was likely in early October. Like the swarm in Southern California near the Baja border, this epicenter is at the third node (120 degrees) from the Banda Sea quake of August 21, 2020 and may have been promoted by energy from that source.

 

O: 03OCT2020 13:41:46  38.1N  112.4W ML=2.6  EMSC   UTAH

O: 03OCT2020 19:25:49  38.1N  112.4W Ml=3.1  EMSC   UTAH

O:  3OCT2020 11:47:45  38.1N  112.5W mb=4.5  EMSC   UTAH                          

P: 11OCT2020 127711    38.6N  112.7W 2.0-3.8 CAAAA  Utah area                  

 

Aftershocks in the area of Brawley, Southern California diminished in number and magnitude today. The strongest was an M 3.6 which NEIC reported was felt with maximum intensity V in San Luis Rio Colorado, Sonora, Mexico and II-III in Brawley and Palm Desert, California and II in Mohave Valley, Arizona. Forecast 127704 had expected this activity was likely around October 2.

 

O: 03OCT2020 23:26:59  33.0N  115.6W Mw=3.6  EMSC   SOUTHERN CALIFORNIA

P:  2OCT2020 127704    33.3N  115.9W 2.5-4.4 AAAAA  So. California             

 

MODERATELY STRONG QUAKE IN SHETLAND ISLANDS

 

EARTHQUAKE SUMMARY FOR OCTOBER  2, 2020

 

The strongest earthquake in the world today was an M 5.8 in the South Shetland Islands. It was not reported felt in this area. This is the largest earthquake in the current swarm which began about a month ago with and M 5.0 on August 29 and most recently an M 4.9 and 4.8 on September 29 and 30. Forecast 127836 had expected today's activity within about 50 km of this epicenter was likely around October 8. This continues the strong activation at high latitudes as described in previous issues of this summary:

 

 

"The full moon will arrive October 1 at 21:05 UT. Enhanced seismicity is expected to be at moderate levels with this full moon which is at local solar midnight near 45 East longitude and 135 West longitude. As it coincides with a strong geomagnetic storm, seismicity is likely to see enhancement in the neighborhood of Turkey and Iran in the east and in Southern Alaska south to the west coast of the U.S. This includes portions of Central and southern California north to southeastern Alaska which are currently active. Some additional vertical seismicity may occur due to reduced friction. A strong earthquake in the next week is considered likely near the geomagnetic equator or at high latitudes." (September 28-30, 2020)

 

and

 

"The geomagnetic field saw major storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 15. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 30, 2020)

 

O:  2OCT2020 10:17:34  62.3S   58.3W Mw=5.8  EMSC   SOUTH SHETLAND ISLANDS       

O:  2OCT2020 12:37:48  62.3S   58.3W mb=4.7  EMSC   SOUTH SHETLAND ISLANDS       

P:  8OCT2020 127836    62.0S   58.0W 3.0-5.6 CAAAA  So. So. America            

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the Gulf of Alaska. It was not reported felt in this area. This is the strongest aftershock of the M 7.9 in the Gulf of Alaska of January 23, 2018 since an M 4.3 on March 24, 2020. Forecast 127771 had expected today's event in the area was likely in early October. 

 

O:  2OCT2020 10:06:43  56.7N  149.5W mb=4.2  EMSC   GULF OF ALASKA               

P:  7OCT2020 127771    55.0N  149.0W 3.0-4.5 BBAAA  Northern Alaska            

 

The swarm of aftershocks in southern California today declined considerably and may end in the next day. No earthquakes of M>=3 were recorded. Those of M>=2.5 are listed below, a more complete listing of events of M>=2 are in the "California" regional section below. Today's activity was expected in forecast 127704 around October 2.

 

O: 02OCT2020 12:13:43  33.0N  115.6W ML=2.7  EMSC   SOUTHERN CALIFORNIA

O: 02OCT2020 14:36:43  33.0N  115.6W Ml=2.5  EMSC   SOUTHERN CALIFORNIA

O: 03OCT2020 01:30:59  33.0N  115.6W ML=2.7  EMSC   SOUTHERN CALIFORNIA

O:  2OCT2020 07:04:10  32.9N  115.6W Ml=2.5  EMSC   SOUTHERN CALIFORNIA          

P:  2OCT2020 127704    33.3N  115.9W 2.5-4.4 AAAAA  So. California              

 

Strong swarms occurred today in the Dominican Republic and in northern Peru today. The activity in the Dominican Republic continues a swarm which has been in operation for about a week. The largest earthquake in this region today was an  M 3.8. Forecast 127653 had expected today's activity in this area around October 2.

 

O: 02OCT2020 14:44:43  18.3N   68.9W ML=3.8  EMSC   DOMINICAN REPUBLIC REGION

O: 02OCT2020 10:04:59  18.6N   69.5W ML=3.3  EMSC   DOMINICAN REPUBLIC

O: 02OCT2020 21:19:44  18.6N   68.9W ML=3.5  EMSC   DOMINICAN REPUBLIC

O: 02OCT2020 23:57:35  18.7N   70.2W ML=3.2  EMSC   DOMINICAN REPUBLIC

O: 02OCT2020 15:53:20  18.9N   69.7W ML=3.3  EMSC   DOMINICAN REPUBLIC

O: 02OCT2020 21:59:44  19.1N   69.3W ML=3.2  EMSC   DOMINICAN REPUBLIC REGION

O: 03OCT2020 00:25:13  19.1N   69.5W ML=3.4  EMSC   DOMINICAN REPUBLIC REGION

O: 02OCT2020 10:31:10  19.2N   69.8W ML=3.4  EMSC   DOMINICAN REPUBLIC

O: 02OCT2020 20:14:53  19.2N   69.6W ML=3.5  EMSC   DOMINICAN REPUBLIC

O:  2OCT2020 20:51:58  20.2N   70.9W ML=3.4  EMSC   DOMINICAN REPUBLIC REGION    

P:  2OCT2020 127653    20.0N   71.0W 3.0-4.3 AAAAA  Bahamas/No. Caribbean      

 

The activity in northern Peru did not have a mainshock but included at least eight events of M 4.4-4.9. Moderate earthquakes in this area are not uncommon with the most recent an M 5.0 on August 3, 2020 and an M 5.2 on February 25, 2020. Neither of these included a strong series. The last similar swarm in this area occurred on February 21-23, 1996 when a strong aftershock sequence followed an M 7.5 about 150 km south of today's epicenter but no similar swarms have hit today's  epicentral region in  at least 30 years. This could expand and include a large earthquake. It may have been promoted by strong tidal or geomagnetic effects. These epicenter are near the local geomagnetic equator. 

 

NEIC reported these earthquakes of M 4.6 in Northern Peru were felt with intensity II-III in the area(s) of Northern Peru at Huarmey, Ancash (VI) and Viru La Libertad.  These events are at the fourth node (90 degrees) from the M 7.8 in the Alaska Peninsula of July 22 and may have been promoted by energy from this source. It is also near the 7th node from the Central Mid-Atlantic of September 18, 2020 and may be related to energy from that location.

 

O: 02OCT2020 11:29:08   8.5S   79.6W mb=4.5  EMSC   NEAR COAST OF NORTHERN PERU

O: 02OCT2020 16:44:40   8.6S   79.9W mb=4.6  EMSC   NEAR COAST OF NORTHERN PERU

O: 02OCT2020 09:24:00   8.7S   80.1W mb=4.6  EMSC   OFF COAST OF NORTHERN PERU

O: 02OCT2020 09:18:23   8.8S   80.2W mb=4.8  EMSC   OFF COAST OF NORTHERN PERU

O: 02OCT2020 19:18:22   8.8S   80.3W mb=4.7  EMSC   OFF COAST OF NORTHERN PERU

O: 02OCT2020 22:26:14   8.8S   80.3W mb=4.4  EMSC   OFF COAST OF NORTHERN PERU

O: 02OCT2020 08:51:18   9.0S   80.6W ML=4.4  EMSC   OFF COAST OF NORTHERN PERU

O:  2OCT2020 09:07:00   8.5S   80.1W mb=4.8  EMSC   OFF COAST OF NORTHERN PERU   

P:  2OCT2020 127618     9.0S   81.0W 4.0-5.3 AAAAA  No. Peru                   

 

 

 

 

 

 

 

STRONG QUAKE IN NEW BRITAIN

 

EARTHQUAKE SUMMARY FOR OCTOBER  1, 2020

 

The strongest earthquake of the day was an M 6.0 in New Britain, Papua New Guinea. NEIC reported it was felt with intensity IV in Lae Morobe, PNG and II in Port Moresby, PNG. This earthquake appears to have been related to the continuing geomagnetic storm combined with high tidal stresses accompanying the full moon today as described in previous issues of this summary:

 

 

 

"The full moon will arrive October 1 at 21:05 UT. Enhanced seismicity is expected to be at moderate levels with this full moon which is at local solar midnight near 45 East longitude and 135 West longitude. As it coincides with a strong geomagnetic storm, seismicity is likely to see enhancement in the neighborhood of Turkey and Iran in the east and in Southern Alaska south to the west coast of the U.S. This includes portions of Central and southern California north to southeastern Alaska which are currently active. Some additional vertical seismicity may occur due to reduced friction. A strong earthquake in the next week is considered likely near the geomagnetic equator or at high latitudes." (September 28-30, 2020)

 

and

 

"The geomagnetic field saw major storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 15. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 30, 2020)

 

The epicenter in New Britain is near the geomagnetic equator. This is the strongest earthquake within about 200 km of this epicenter since an M 6.2 on July 15, 2019 about 150 km northeast of today's epicenter. Forecast 127339 and 127616 had expected this activity was likely in this area between September 29 and October 4. This earthquake is near the antipode of the M 6.8 in the Mid-Atlantic of September 18 and was probably related to focused energy from that event.

 

O:  1OCT2020 10:34:45   6.0S  148.6E Mw=6.0  EMSC   NEW BRITAIN REGION, P.N.G.   

P:  4OCT2020 127616     6.0S  148.0E 4.0-5.3 BAAAA  New Ireland                

P: 29SEP2020 127339     7.0S  147.0E 4.0-5.4 AABAA  New Ireland                

 

The strongest earthquake in the U.S. or Canada today was an M 5.2 in the eastern Andreanof Island, Aleutians, Alaska. This is the strongest earthquake within about 150 km of this epicenter since an M 6.3 on November 24, 2018 and prior to that an M 5.2 on July 9, 2018. Forecast 127749 had expected today's event in this area around October 2.

 

O:  1OCT2020 10:25:08  51.7N  175.0W Mw=5.2  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  2OCT2020 127749    51.6N  177.6W 3.5-4.8 AABAA  Andreanoff Isls, Aleutians 

 

The swarm of earthquakes in Southern California continued today. The largest

of these were M 3.4, 3.5, 3.5, 3.6 and 3.7. Following is a listing of aftershocks in Southern California in the past 24 hours of M>=3.0. A more complete listing of M>=2.0 can be found in the "California" regional section below. Forecast 127442 and 127704 had expected today's activity around September 29 to October 2.

 

NEIC reported these earthquakes of M 3.0-4.0  in Southern California  were felt with intensity II-IV in the area(s) of Southern California at Calipatria and Brawley and other regional population centers.

 

O: 01OCT2020 07:10:24  33.1N  115.6W Ml=3.1  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 12:46:37  33.1N  115.6W ML=3.3  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 13:23:13  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 13:35:38  33.1N  115.6W ML=3.2  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 14:46:41  33.1N  115.6W Mw=3.6  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 15:21:40  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 21:42:37  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 22:47:30  33.1N  115.6W ML=3.5  EMSC   SOUTHERN CALIFORNIA

O: 02OCT2020 06:08:19  33.1N  115.6W ML=3.5  EMSC   SOUTHERN CALIFORNIA

O: 02OCT2020 06:08:27  33.1N  115.6W ML=3.7  EMSC   SOUTHERN CALIFORNIA

O: 02OCT2020 06:08:50  33.1N  115.6W ML=3.4  EMSC   SOUTHERN CALIFORNIA

P:  2OCT2020 127704    33.3N  115.9W 2.5-4.4 AAAAA  So. California             

P: 29SEP2020 127442    32.8N  116.0W 2.5-4.7 AAAAA  So. California             

 

An unusual earthquake of M 5.1 occurred today in the Dodecanese Islands of Greece. This event is the strongest earthquake within about 150 km of today's epicenter since an M 5.4 on December 10, 2019 and prior to that an M 6.6 on July 29, 2017. Forecast 127691 had expected today's event in this area was likely in early October.

 

O:  1OCT2020 11:05:37  36.7N   26.7E mb=5.1  EMSC   DODECANESE ISLANDS, GREECE   

P:  3OCT2020 127691    37.0N   26.0E 3.0-4.4 AAAAA  No. Greece                 

 

SEISMICITY IN TONGA; SO. CALIFORNIA TIED TO FULL MOON; GEOMAGNETIC STORM

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 30, 2020

 

The strongest earthquake in the world today was an M 6.4 in Tonga. NEIC reported it was felt with intensity V in Tonga at Neiafu, Vavau and in Nuku'alofa, Tongatapu. This event occurred  near the geomagnetic equator near local solar noon and was probably enhanced by tidal stresses from the full moon which arrived today as previously noted in this report:

 

"The full moon will arrive October 1 at 21:05 UT. Enhanced seismicity is expected to be at moderate levels with this full moon which is at local solar midnight near 45 East longitude and 135 West longitude. As it coincides with a strong geomagnetic storm, seismicity is likely to see enhancement in the neighborhood of Turkey and Iran in the east and in Southern Alaska south to the west coast of the U.S. This includes portions of Central and southern California north to southeastern Alaska which are currently active. Some additional vertical seismicity may occur due to reduced friction. A strong earthquake in the next week is considered likely near the geomagnetic equator or at high latitudes." (September 28-30, 2020)

 

and

 

"The geomagnetic field saw major storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 15. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 30, 2020)

 

The last earthquake of M>=6.5 in the region of Tonga within about 200 km of today's epicenter was an M 6.6 on November 4, 2019 and prior to that on April 28, 2012 with M 6.7. Forecast 127561 had expected today's event was likely around September 29 within about 50 km of the epicenter. This epicenter is at 144 degrees from the M 6.8 of September 18 in the mid-Atlantic and may have been promoted by concentrated energy from that source.

 

O:  1OCT2020 01:13:33  19.5S  174.2W Mw=6.5  EMSC   TONGA                        

P: 29SEP2020 127561    19.0S  174.0W 4.0-5.6 AAAAA  Tonga Islands              

 

A strong series of light to moderate earthquakes shook the area near the southern California border with Baja California, Mexico. Many of these events were felt in Calipatria, California. The strongest of today's events was an M 5.0. It was reported felt with intensity VI in Westmorland, V in Calipatria, Brawley; IV in Imperial, El Centro, Calexico and Mexicali, Baja California and II-III in Thermal, Holtville and Heber, California  and as far as 350 km away in Nevada, Arizona, and Utah. The strongest aftershock was an M 4.5. NEIC reported it was felt with intensity IV in California at Calipatria, Brawley and El Centro and II-III in Imperial, Holtville, Heber, Calexico, Mexicali, and in Baja California at Mexicali, Puebla Baja and Jacumba among others. Stresses from Hurricane Marie, currently located south of Baja California, Mexico may have helped promote today's activity in Baja California. This summary had reported on Marie in previous issues as:

 

"Hurricane Marie continued south of Baja California, Mexico today with winds up to 80 kts. This system is currently  expected to track to the northwest but not to impact regional seismicity at this time." (September 30, 2020)

 

Today's event of M 4.9-5.0 is the largest within about 75 km of today's epicenter on the Baja-Southern California border region since an M 5.5  on August 26, 2012. Forecast 127442 had expected today's event was likely in this region around September 29. Following is a listing of events of M>=3.0 in the area in the past 24 hours. A more extensive listing of events of M>=2.0 can be found in the "California" section of this summary. This activity is at the third node (120 degrees) from the M 6.8 in the Banda Sea of August 21 and at the fourth node (90 degrees) from the M 6.8 in the central mid-Atlantic of September 18 and may have been encouraged by energy from those sources.

 

O: 01OCT2020 00:33:48  33.0N  115.6W ML=3.8  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 00:36:30  33.0N  115.6W ML=3.2  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:10:25  33.0N  115.6W Mw=4.1  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:06:02  33.0N  115.6W ML=3.5  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:31:51  33.0N  115.6W Mw=4.2  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 00:31:26  33.1N  115.6W Mw=5.0  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:05:05  33.1N  115.6W ML=3.5  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:06:22  33.1N  115.6W ML=3.1  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:11:05  33.1N  115.6W ML=3.4  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:15:53  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:17:36  33.1N  115.6W ML=3.2  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 01:46:51  33.1N  115.7W ML=3.2  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 03:31:00  33.1N  115.6W Ml=3.5  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 03:32:57  33.1N  115.6W ML=3.4  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 03:36:33  33.1N  115.6W Mw=4.4  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 03:38:28  33.1N  115.6W ML=3.1  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 03:40:16  33.1N  115.6W ML=3.5  EMSC   SOUTHERN CALIFORNIA

O: 01OCT2020 06:57:58  33.1N  115.6W Ml=3.5  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:08:25  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:15:30  33.1N  115.6W ML=3.2  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:19:47  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:21:08  33.1N  115.6W ML=2.7  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:29:00  33.1N  115.6W ML=2.1  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:31:11  33.1N  115.6W ML=2.5  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:33:33  33.1N  115.6W ML=3.2  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:38:06  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

O: 30SEP2020 23:45:03  33.1N  115.6W ML=3.0  EMSC   SOUTHERN CALIFORNIA

P: 29SEP2020 127442    32.8N  116.0W 2.5-4.7 AAAAA  So. California             

 

 

An unusual earthquake series, including an M 4.4 and 4.5, occurred today in the Spanish Pyrenees. NEIC reported the N 4.4 was felt with intensity IV in Galar Navarra, Spain and in Zaragaza, Spain. The M 4.5 was felt with intensity Vin Spain at Atarrabia, Lizoain, Navarra and II-III in Burlata, Pamploma, Baranain, Erro, Zaragoza, Spain and in France at Biarritz, Esterre and Saint-Martin-d'Arrossa. While an M 3.7 hit near this epicenter on August 20 and an M 3.1 on September 23, 2020, this is the largest event within about 200 km of this epicenter since an M 4.8 on December 30, 2012 and prior to that an M 4.6 on May 18, 2008. Forecast 127470 had expected today's activity was likely around September 27. These epicenters are at 103 degrees from the M 6.8 in  Sumatra of August 18, 2020 and may have been promoted by concentrated energy from that source.

 

O:  1OCT2020 00:21:37  42.8N    1.5W mb=4.4  EMSC   PYRENEES                     

O: 30SEP2020 22:02:30  42.8N    1.5W mb=4.5  EMSC   PYRENEES

P: 27SEP2020 127470    42.0N    2.0E 3.0-5.3 BABAA  France                     

 

MODERATELY STRONG SEISMICITY CONTINUES IN TAIWAN

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 29, 2020

 

Moderate seismicity continued today in the region of Taiwan. An M 5.1-5.9 was recorded off northeastern Taiwan. This is the strongest earthquake in the world today. It follows a smaller event of M 5.3 off the southeastern coast of Taiwan yesterday. The last event recorded by NEIC within about 200 km of today's event occurred August 7, 2019 with M 5.9. This followed events of M 6.1 and M 6.4 on February 4 and 6, 2018 and an M 6.1 on April 18, 2029.

 

NEIC reported this earthquake of M 5.1 in Taiwan  was felt with intensity IV in Hsinchu, Taiwan and II-III in the area(s) of Taiwan at Keelung, Taipei, Taoyuan, and Changhua. CWB reported today's earthquake was M 5.9 and was felt with intensity IV in Hsinchu; III in Taoyuan, Miaoli, Taipei, Yunlin, Hualien, Yilan, Taichung; II Changhua, Taitung, Chiayi in and I in Kaohsiung   and Tainan Counties, Taiwan. Forecast 127403 had expected today's event within about 150 km of this epicenter around September 30.

 

O: 30SEP2020 04:37:19  24.9N  122.1E Mw=5.1  EMSC   TAIWAN REGION                

O: 30SEP2020 04:37:20  24.9N  122.1E ML=5.9  TAI    Hualien, Taiwan              

P: 30SEP2020 127403    24.0N  123.0E 4.0-5.4 AAAAA  Taiwan                     

 

An unusual earthquake of M 4.3 shook areas of Malta in the Mediterranean south of Italy today. NEIC reported maximum intensity V in Malta at Safi; IV in Zurrieq, Siggiewi, and Santa Lucia and II-III in Orendi, Birzebugia, Gudja, Dingli, Paola and Luqa. This is the largest earthquake felt within about 100 km of this epicenter in Malta within the past 30 years. Forecast 127424 had expected this activity was likely to the north around September 29. This epicenter is at 103 degrees from the M 6.8 in Atacama, Chile of September 1; at the seventh node (51.4 degrees) from the Central Atlantic event of M 6.7 on September 18, 2020   and at the fourth node (90 degrees) from the M 6.8 in Sumatra of August 18, 2020 and was probably promoted by concentrated energy from these sources.

 

O: 30SEP2020 01:01:01  35.7N   14.4E mb=4.3  EMSC   MALTA REGION                 

P: 29SEP2020 127424    39.0N   14.0E 3.0-4.6 ACAAA  Mediterranean/Sicily       

 

An earthquake of M 4.7 also occurred in the North Atlantic west of Portugal

This is the strongest earthquake within about 250 km of this epicenter since an M 4.8 on February 29, 2020, the only other such event in this area in the past 30 years. It was expected to occur in this area around September 29  in forecast 127425.

 

O: 30SEP2020 02:42:46  35.4N   14.9W mb=4.7  EMSC   AZORES-CAPE ST. VINCENT RIDGE

P: 29SEP2020 127425    37.0N   11.0W 3.5-5.0 ABCAA  Morocco/Spain              

 

A series of light earthquakes shook the San Francisco Bay area of California today. The largest of these was an M 3.3 which NEIC reported was felt in the San Francisco Bay area with intensity II-III in Milpitas, Fremont, Sunol, San Jose among others. The mainshock of M 3.3 was followed by events of M 2.7, 2.8 and others. This activity may have been promoted by the current geomagnetic storm combined with high tidal stresses associated with the current full moon. This summary had noted these possibilities in this summary as:

 

"The full moon will arrive October 1 at 21:05 UT. Enhanced seismicity is expected to be at moderate levels with this full moon which is at local solar midnight near 45 East longitude and 135 West longitude. As it coincides with a strong geomagnetic storm, seismicity is likely to see enhancement in the neighborhood of Turkey and Iran in the east and in Southern Alaska south to the west coast of the U.S. This includes portions of Central and southern California north to southeastern Alaska which are currently active. Some additional vertical seismicity may occur due to reduced friction. A strong earthquake in the next week is considered likely near the geomagnetic equator or at high latitudes." (September 29, 2020)

 

and

 

"The geomagnetic field saw active conditions today. The AP level was 16.  High latitude geomagnetic field also saw stormy conditions with AP 31. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 27-29, 2020)

 

It is likely that tidal stresses will continue to promote seismicity in  the region of California over the next several days. Today's activity began with an M 3.4 and 3.5 yesterday. At the time this summary noted in this regard:

 

 

"A series of light earthquakes were felt widely in the San Francisco Bay area of California today. The largest of these of M 3.4 and 3.3 occurred near local solar midnight and noon and were probably promoted by tidal and geomagnetic effects which maximize near this hour. NEIC reported these earthquake of M 3.4 in San Francisco, California  was felt with intensity II-III in the area(s) of San Francisco, California at Miliptas, Fremont, Sunol, San Jose, Santa Clara.

An earlier M 3.4 in San Francisco today was felt with intensity II-III in Milpitas, Fremont, Sunol, San Jose. Similar earthquakes of M 3.4-3.5 occurred near today's epicenters on August 27 and June 17, 2020 but the last of larger magnitude within about 40 km of today's events occurred on January 2, 2020.

Forecast 127411 had expected today's activity in this area was likely around September 25." (September 28, 2020)

 

O: 29SEP2020 15:16:27  37.5N  121.8W Md=2.7  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 29SEP2020 15:36:09  37.5N  121.8W ML=2.8  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 29SEP2020 16:02:30  37.5N  121.8W Mw=3.3  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 29SEP2020 16:52:02  37.6N  121.8W Md=2.0  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 29SEP2020 17:06:13  37.6N  121.8W Md=2.2  EMSC   SAN FRANCISCO BAY AREA, CALIF.

P: 29SEP2020 127411    37.8N  122.6W 2.5-4.4 AAAAA  Central California         

 

An M 4.5 aftershock in the region of Southwestern Puerto Rico was widely felt today. NEIC reported this earthquake of M 3.9-4.5 in Southwestern Puerto Rico was felt with intensity IV in Cabo Rojo and Yauco, Puerto Rico II-III in the area(s) of Puerto Rico at Lajas,San German, Sabana Grande, Guanica, Hormigueros, Mayaguez, and Lares. A series of lightly felt aftershock also occurred today.

This is the strongest aftershock in this zone since an M 4.8 on August 7 and an M 5.3 on July 3, 3030. Forecast 127381 had expected today's event in this region was likely around September 29.

 

O: 29SEP2020 22:57:11  17.9N   67.1W ML=3.4  EMSC   PUERTO RICO REGION

O: 30SEP2020 04:41:12  17.9N   67.1W Md=3.0  EMSC   PUERTO RICO REGION

O: 29SEP2020 13:29:59  18.0N   67.1W mb=4.5  EMSC   PUERTO RICO REGION           

P: 29SEP2020 127381    19.0N   67.0W 3.4-4.9 AAAAA  Puerto Rico                

 

M

MODERATE QUAKE SHAKES SOUTHERN TAIWAN

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 28, 2020

 

The strongest earthquake in the world today was an M 4.9-5.3 in southern Taiwan.

CWB reported the M 5.3 was felt with intensity IV in Taitung and Pingtung; III in Kaohsiung, II in Chiaya, Hualien, Nantou, Yunlin and Changhua Counties, Taiwan. The event of M 4.4 was felt with intensity IV in Taitung; III in Pingtung and I in Kaohsiung, and Tainan Counties, Taiwan. NEIC reported this earthquake of M  4.9 in Taiwan  was felt with intensity II-III in the area(s) of  Taiwan at Pingtung County. A similar event of M 5.1 occurred earlier in the day and was felt with intensity VI in Taitung and Kaohsiung and III in Pingtung Counties, Taiwan. The last earthquake in southern Taiwan of M>=5.3 was an M 5.9 on April 10, 2020 and an M 5.7 on July 27, 2019. Forecast 127402 had expected this earthquake was likely around September 30.

 

O: 28SEP2020 20:50:54  22.4N  121.0E ML=5.3  TAI    Hualien, Taiwan              

O: 28SEP2020 20:50:55  22.4N  121.0E Mw=4.9  EMSC   TAIWAN REGION

O: 29SEP2020 01:14:17  22.4N  121.0E Mw=4.9  EMSC   TAIWAN REGION

O: 28SEP2020 19:05:08  22.4N  121.0E ML=4.4  TAI    Hualien, Taiwan              

O: 28SEP2020 19:05:08  22.4N  121.0E ML=4.4  EMSC   TAIWAN REGION                 

P: 30SEP2020 127402    21.0N  120.0E 4.0-5.5 ABAAA  Taiwan                     

 

A series of moderate earthquakes including three of M 4.9 occurred near local solar noon in the Azores Islands in the northern mid-Atlantic and was probably promoted by tidal effects which maximize near this hour. The only earthquake in the Azores of M>=4.9  in the past year was an M 5.1 about 500 km southwest of this epicenter on March 8, 2020. The last such quake within about 200 km of today's epicenters occurred as an M 5.4 about 150 km to the northeast of today's epicenter on April 29, 2019. Forecast 127485 had expected this activity was likely in the Azores around September 28.

 

NEIC reported this earthquake of M 4.9 in the Azores, Portugal  was felt with intensity II-III in the area(s) of the Azores, Portugal at Rabo de Peixe.

 

O: 28SEP2020 13:21:06  41.8N   29.4W mb=4.9  EMSC   AZORES ISLANDS REGION

O: 28SEP2020 12:26:52  41.9N   29.2W mb=4.9  EMSC   AZORES ISLANDS REGION

O: 28SEP2020 12:30:32  41.6N   29.5W mb=4.9  EMSC   AZORES ISLANDS REGION        

P: 28SEP2020 127485    40.0N   30.0W 4.0-5.6 ABAAA  No. Mid-Atlantic Ridge     

 

An earthquake of M 5.0 occurred today in the Volcano Islands of Japan. This event was not reported felt. Tropical Storm passed to the east of the Volcano

Islands two days ago and may have helped promote today's event in the Volcano Islands.

 

"TD Kujira formed today east of the Volcano Islands, Japan with winds up to 40 kts. It is expected track to the north into the north Pacific and not to threaten seismicity or landfall in this area." (September 27-28, 2020)

 

The last earthquake within about 200 km of today's epicenter with M>=5 occurred on  March 26, 2020. Forecast 127404 had expected today's event was likely around September 24-30 2020.

 

O: 29SEP2020 04:38:46  22.1N  144.3E mb=5.0  EMSC   VOLCANO ISLANDS, JAPAN REGION

P: 24SEP2020 127404    22.0N  144.0E 4.0-5.4 BAAAA  Volcano Islands            

P: 30SEP2020 127404    24.0N  143.0E 4.0-5.4 ABAAA  Volcano Islands             

 

An earthquake of M 5.0-5.1 also occurred today south of the Volcano Islands in Guam. NEIC reported this earthquake of M  5.1 in Guam  was felt with intensity II-III in the area(s) of Guam at Tamuning. Similar stresses from Kujira may be helping to promote seismicity in this area as in the Volcano Islands. Forecast 127382 had expected today's event in Guam around September 27.

 

O: 29SEP2020 01:03:52  13.5N  146.0E mb=5.0  EMSC   GUAM REGION                  

O: 29SEP2020 01:03:52  13.5N  146.0E mb=5.1  ANSS   GUAM REGION                  

P: 27SEP2020 127382    12.0N  145.0E 4.0-5.5 ABAAA  So. Marianas/Guam          

 

The strongest earthquake in the U.S. or Canada today was an aftershock of M 4.3 of the M 5.8 of September 27. The aftershock sequence of that event has included an M 5.2 of September 28 as reported in the previous summary:

 

 

"The strongest seismicity in the U.S. or Canada continued in the Fox Islands today with an M 4.6 near local solar midnight and a later M 5.2. These events were not reported felt in this remote area. The event near local solar midnight was probably enhanced by tidal and geomagnetic effects. The geomagnetic field remained at strong storm levels today as reported in this summary:

 

"The geomagnetic field saw minor storm conditions today. The AP level was 24.  High latitude geomagnetic field also saw stormy conditions with AP 22. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days.." (September 27, 2020)

 

The activity in the Fox Islands was anticipated in forecast 127514 within about 50 km of this activity.  The mainshock of M 5.8 yesterday was the strongest earthquake in the Fox Islands within about 200 km of this epicenter since August 16, 2020 and prior to that an M 5.8 on October 25, 2019. The last such event of larger magnitude than M 5.8 in this area was an M 5.9 on August 25, 2018. The last of M>=6 was an M 6.9 on July 27, 2015.." (September 28, 2020)

 

Forecast 127510 had expected today's event was likely within about 100 km  around September 29.

 

O: 29SEP2020 01:15:14  52.0N  169.6W mb=4.3  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 29SEP2020 127510    52.4N  170.7W 3.5-4.9 AAAAA  Andreanoff Isls, Aleutians 

 

 

ODERATE QUAKE SHAKES GUATEMALA

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 27, 2020

 

The strongest earthquake in the world today was an M 5.3 in Guatemala. It was felt with intensity V in San Bartolome, Sacatepequez; IV in San Jose and Pueblo Nuevo Vinas Santa Rosa and II-III in Palin Escuintla, Amatitlan, Antigua, Jocotenango, Taxisco, El Tejar and Mixco. This is the strongest earthquake in Guatemala within about 100 km of this epicenter since an M 5.9 on December 19, 2019 and three in November, 2019 of M 5.5-5.6. Forecast 127364 had expected today's event within about 25 km was likely around September 28-29.

 

O: 27SEP2020 09:40:55  14.2N   90.8W Mw=5.3  EMSC   GUATEMALA                    

P: 28SEP2020 127364    13.0N   90.0W 3.5-5.3 ABAAA  Guatemala                   

P: 29SEP2020 127364    14.0N   91.0W 3.5-5.5 AAAAA  Guatemala                  

 

Enhanced seismicity also continued today at high latitudes. This included toda an M 4.7 in the Greenland Sea, an aftershock of M 5.2 in the Fox Islands, Alaska, several moderate events in South Island, New Zealand and an M 4.8 in the Aegean Sea among others.

 

The M 4.7 in the Greenland Sea was the largest in this area in nearly a year - since an M 4.8 on December 18, 2019 and prior to that an M 4.8 on January 16, 2019. Today's event was not reported felt in this remote area. Forecasts 127550 and 127546 had expected today's activity at the end of September. This earthquake is at 102 degrees from the Banda Sea quake of M 6.8 in the Banda Sea on August 21, 2020. Earthquakes in the Aegean Sea of Greece are also occurring at 103 degrees from the Banda Sea.

 

O: 27SEP2020 10:02:36  75.6N    6.8E mb=4.7  EMSC   GREENLAND SEA                

P: 29SEP2020 127550    72.0N    0.0E 3.0-4.5 ACAAA  Norway                     

P: 30SEP2020 127546    79.0N    7.0E 4.0-5.4 BCAAA  Arctic Ocean Region        

 

The strongest seismicity in the U.S. or Canada continued in the Fox Islands today with an M 4.6 near local solar midnight and a later M 5.2. These events were not reported felt in this remote area. The event near local solar midnight was probably enhanced by tidal and geomagnetic effects. The geomagnetic field remained at strong storm levels today as reported in this summary:

 

"The geomagnetic field saw minor storm conditions today. The AP level was 24.  High latitude geomagnetic field also saw stormy conditions with AP 22. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days.." (September 27, 2020)

 

The activity in the Fox Islands was anticipated in forecast 127514 within about 50 km of this activity.  The mainshock of M 5.8 yesterday was the strongest earthquake in the Fox Islands within about 200 km of this epicenter since August 16, 2020 and prior to that an M 5.8 on October 25, 2019. The last such event of larger magnitude than M 5.8 in this area was an M 5.9 on August 25, 2018. The last of M>=6 was an M 6.9 on July 27, 2015.

 

O: 27SEP2020 08:17:49  52.0N  169.7W ml=3.6  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

O: 28SEP2020 02:44:19  52.0N  169.7W Mw=5.2  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

O: 27SEP2020 10:51:07  51.8N  169.8W mb=4.6  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 25SEP2020 127514    52.4N  169.4W 3.5-4.9 AAAAA  Fox Islands, Aleutians     

 

Moderate earthquakes of M 4.6 also occurred today in the Alaska Peninsula and in Central Alaska with M 4.2. Forecast 127507 had expected the Alaska Peninsula event was likely around September 27.  An earthquake of M 4.9 in this region on September 25 broke a two-month quiet in the area at this magnitude level as noted in the September 25 summary:

 

".. Alaska Peninsula as an aftershock of the July 22, 2020 M 7.8 in the Alaska Peninsula. This is the strongest aftershock in the Alaska Peninsula since an M 5.0 on August 20 and the largest within about 100 km of the mainshock since an M 5.2 on August 9, 2020." (September 25, 2020)

 

Most of this activity in Alaska is at 102-103 degrees from recent large earthquakes of M 6.8 in Sumatra and in the Central Mid-Atlantic.

 

O: 28SEP2020 06:32:15  55.5N  158.3W mb=4.6  EMSC   ALASKA PENINSULA             

P: 27SEP2020 127507    55.0N  159.7W 3.5-5.4 AAAAA  Alaska Peninsula           

 

The M 4.2 in Central Alaska had been expected to occur around September 29 within about 10 km of this epicenter. 

 

NEIC reported this earthquake of M 3.7-4.2 in Central Alaska  was felt with intensity II-III in the area(s) of Central Alaska at Cantwell, Talkeetna and Chugiak.  NEIC reported the earthquake of M 3.2 in  Central Alaska was felt with intensity II-III in the area(s) of Central Alaska at Cantwell and Healy.  Forecast 127538 had expected the M 4.2 was likely within about 10 km of this this epicenter around September 29.

 

O: 28SEP2020 02:40:22  62.3N  150.5W ML=3.2  EMSC   CENTRAL ALASKA               

O: 28SEP2020 03:41:30  63.0N  150.2W mb=4.2  EMSC   CENTRAL ALASKA               

P: 29SEP2020 127538    62.9N  150.2W 3.2-4.9 AAAAA  Central Alaska             

 

A series of light earthquakes were felt widely in the San Francisco Bay area of California today. The largest of these of M 3.4 and 3.3 occurred near local solar midnight and noon and were probably promoted by tidal and geomagnetic effects which maximize near this hour. NEIC reported these earthquake of M 3.4 in San Francisco, California  was felt with intensity II-III in the area(s) of San Francisco, California at Miliptas, Fremont, Sunol, San Jose, Santa Clara.

An earlier M 3.4 in San Francisco today was felt with intensity II-III in Milpitas, Fremont, Sunol, San Jose. Similar earthquakes of M 3.4-3.5 occurred near today's epicenters on August 27 and June 17, 2020 but the last of larger magnitude within about 40 km of today's events occurred on January 2, 2020. Forecast 127411 had expected today's activity in this area was likely around September 25.

 

O: 27SEP2020 22:54:06  37.5N  121.9W ML=3.4  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 28SEP2020 05:16:36  37.5N  121.8W ML=3.4  ANSS   SAN FRANCISCO BAY AREA, CALIF.

O: 28SEP2020 05:16:36  37.5N  121.8W ML=3.3  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 28SEP2020 05:24:41  37.5N  121.8W Md=2.1  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 28SEP2020 06:03:47  37.5N  121.8W Md=2.1  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 27SEP2020 15:12:06  37.5N  121.8W Md=2.3  EMSC   SAN FRANCISCO BAY AREA, CALIF.

P: 25SEP2020 127411    37.2N  122.1W 2.5-4.4 AAAAA  Central California         

 

An aftershock of M 2.7 shook the region of Cape Town South Africa today. This follows an unusual event of M 2.9 yesterday. This summary noted in regard  to that earthquake in the previous summary:

 

"An unusual earthquake of M 2.9 was felt in the Western Cape area of South Africa today with intensity II-III in Atlantis, Cape Town, Stellenbosch, Port Elizabeth,  Knysna, George, Hermanus, Somerset, Paarl, Durban and Somerset.

This is the strongest earthquake in the region of Capetown, South Africa within about 300 km of today's epicenter since in at least 30 years and the strongest in southern South Africa since an M 4.1 about 300 km to the east on May 14, 2011 and an M 4.3  near that epicenter on November 5, 2009. These are the only such events in southern South Africa in the past 30 years. Today's event occurred about an hour-and-a-half after the M 6.1 South of Africa and may have been enhanced by energy from that regional source." (September 26-27, 2020)

 

NEIC reported today's earthquake of M 2.7 in the Western Cape Province of South Africa  was felt with intensity II-III in the area(s) of the Western Cape Province of South Africa at Stellenbosch, Paarl, Somerset, Cape Town, Atlantis, Worcester and Saldanha.

 

O: 27SEP2020 07:12:54  33.8S   18.8E ML=2.7  EMSC   SOUTH AFRICA                 

 

GEOMAGNETIC STORM INTENSIFIES; ASSOCIATED WITH HIGH LATITUDE SEISMICITY

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 26, 2020

 

The strongest earthquake in the world today was an M 6.1 south of Africa. NEIC reported it was felt in the western Cape Province of South Africa, but this felt activity was probably related to a later M 2.9 near Capetown. 

 

"The geomagnetic field saw minor storm conditions today. The AP level was 27.  High latitude geomagnetic field also saw stormy conditions with AP 48. This is the strongest geomagnetic disturbance since October 25, 2019 when the AP index reached 29 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 26, 2020)

 

The earthquake south of Africa of M 6.1 occurred at a high southern latitude and was probably promoted by the geomagnetic storm. It is the strongest within about 300 km of this epicenter since an M 6.2 to the northeast on November 17, 2014.

The last event within about 250 km of this epicenter was an M 6.2-6.3 on May 9, 2003, the only such event in the past 30 years. Forecast 127593 had expected today's event was likely in this area in late September. The antipode of today's event south of Africa is in Southern Alaska where local seismicity is not common (48N 148W). An event in the Fox Islands, Alaska today of M 5.8 may be related to this earthquake.

 

O: 26SEP2020 17:10:23  48.1S   31.7E Mw=6.1  EMSC   SOUTH OF AFRICA              

P: 30SEP2020 127593    51.0S   29.0E 4.0-5.5 BBBAA  Atlantic-Indian Ridge      

 

An unusual earthquake of M 2.9 was felt in the Western Cape area of South Africa today with intensity II-III in Atlantis, Cape Town, Stellenbosch, Port Elizabeth,  Knysna, George, Hermanus, Somerset, Paarl, Durban and Somerset.

This is the strongest earthquake in the region of Capetown, South Africa within about 300 km of today's epicenter since in at least 30 years and the strongest

in southern South Africa since an M 4.1 about 300 km to the east on May 14, 2011 and an M 4.3  near that epicenter on November 5, 2009. These are the only such events in southern South Africa in the past 30 years. Today's event occurred about an hour-and-a-half after the M 6.1 South of Africa and may have been enhanced by energy from that regional source.

 

O: 26SEP2020 18:41:41  33.6S   18.6E mb=2.9  EMSC   SOUTH AFRICA                 

 

An unusual earthquake, also at high latitudes, also occurred today in the Pacific-Antarctic Ridge. It was not reported felt in this remote oceanic area. The last event of M>=4.7 within about 300 km of today's epicenter was an M 5.4 on March 26, 2019.

 

O: 27SEP2020 00:35:26  57.3S  147.8W mb=4.7  EMSC   PACIFIC-ANTARCTIC RIDGE      

 

An earthquake of M 4.1 was widely felt in southwestern Puerto Rico today. NEIC reported intensity V in Puerto Rico at Lajas; IV in Cabo Rojo, Guanica, Sabana Grande, Hormigueros and II-III in San German, Mayaguez, Las Marias and Anasco. It was followed by a series of light aftershocks felt in the same area.

Forecasts 12780 and 12781 had expected this activity between September 25 and 29.

 

O: 26SEP2020 10:55:02  17.9N   67.1W ML=3.4  EMSC   PUERTO RICO REGION

O: 26SEP2020 12:40:02  17.9N   67.1W Md=3.0  EMSC   PUERTO RICO REGION

O: 27SEP2020 04:26:40  17.9N   67.1W ML=3.8  EMSC   PUERTO RICO REGION

O: 27SEP2020 04:32:09  17.9N   67.1W Md=3.4  EMSC   PUERTO RICO REGION

O: 27SEP2020 04:36:36  17.9N   67.1W Md=3.2  EMSC   PUERTO RICO REGION

O: 27SEP2020 04:39:36  17.9N   67.1W ML=3.3  EMSC   PUERTO RICO REGION

O: 26SEP2020 11:26:27  18.0N   67.1W Md=3.3  EMSC   PUERTO RICO REGION

O: 26SEP2020 11:38:38  18.0N   67.1W ML=3.6  EMSC   PUERTO RICO REGION

O: 26SEP2020 11:38:38  18.0N   67.1W ML=3.6  EMSC   PUERTO RICO REGION

O: 26SEP2020 16:19:35  18.0N   68.6W ML=3.2  EMSC   DOMINICAN REPUBLIC REGION

O: 26SEP2020 21:31:39  18.0N   67.0W Md=3.0  EMSC   PUERTO RICO REGION

O: 26SEP2020 11:14:43  17.8N   67.1W ML=3.2  EMSC   PUERTO RICO REGION           

O: 27SEP2020 04:29:04  18.0N   67.1W ML=3.5  EMSC   PUERTO RICO                  

P: 25SEP2020 127380    18.0N   66.0W 3.4-4.9 AAAAA  Puerto Rico                

P: 29SEP2020 127381    19.0N   67.0W 3.4-4.9 AAAAA  Puerto Rico                

 

 

The swarm in Iceland continued and took an unusual turn to the south where an M 4.7 occurred about 200 km south of yesterday's event. In the previous summary this activity had been described as:

 

"Seismicity at high latitudes also continued today with the geomagnetic storm. High AP indices at high latitudes and the continuance of this storm over the

 next several days is likely to lead to further and stronger activity at high latitudes. These include area of Alaska, Kamchatka and northern Europe in the north and areas south of Africa and South America in the south. The most active area was north of Iceland where a series of earthquakes began near local solar midnight with an M 4.1 and also included events of M 4.2 and 3.9 in the aftershock sequence.  A similar sequence in this region of Iceland followed earthquakes up to M 6.0 on June 20-21 about 100 km southwest of today's events." (September 26, 2020)

 

The last earthquake within about 100 km of today's M 4.7 with equal or greater magnitude was an M 4.8 on April 20, 2020. Forecast 127539 had expected today's M 4.7 was likely around September 27.

 

Today's activity in Iceland is at 103 degrees from Atacama Chile where an M 6.8 occurred on September 1 and a similar distance from the M 6.8 in Sumatra of August 18 and may have been enhanced by energy from those sources. Seismic energy is concentrated on the surface of the earth at distances of 101-104 degrees from strong events and can help trigger additional seismicity at those distances.

 

 

O: 26SEP2020 10:28:36  66.6N   17.8W ML=3.0  EMSC   ICELAND REGION

O: 27SEP2020 05:50:58  66.6N   17.8W ML=3.1  EMSC   ICELAND REGION

O: 27SEP2020 00:06:12  64.7N   17.7W mb=4.7  EMSC   ICELAND                      

P: 25SEP2020 127539    66.0N   17.0W 3.0-4.9 ABAAA  Iceland area               

 

Another moderate earthquake today at high latitudes occurred in North Island, New Zealand. NEIC reported this earthquake of M 4.7 in North Island, New Zealand,   was felt with intensity II-III in the area(s) of North Island, New Zealand  in Taumarunui, Manaatu-Wanganui (V); Waitara, Taranaki, New Plymouth (IV) and II-III in Wanganui, Turangi, Te Awamutu, Palmerston North, Cambridge, Hamilton and Picton. GEONET reported this earthquake was felt with moderate intensity in southeastern North Island. More than 11535 people reported feeling this earthquake. Light to moderate intensity was reported throughout much of southern and eastern North Island and northern South Island. 4557 reports of weak intensity;  4494 of light intensity; 2012 with moderate; 353 with strong shaking and 23 with severe and 6 with extreme intensity. The last earthquake of M>=4.7 within about 100 km of this epicenter of equal or greater magnitude was an M 6.1 on October 30, 2018 and prior to that an M 5.7 on July 7, 2012. Today's event in North Island had been expected in this area around September 24.

 

O: 27SEP2020 03:47:24  39.1S  174.9E mb=4.7  EMSC   NORTH ISLAND OF NEW ZEALAND  

O: 27SEP2020 03:47:23  39.2S  174.9E MS=5.4  GEONET Felt with moderate intensity

P: 24SEP2020 127588    40.0S  174.0E 3.0-4.4 BAAAA  North Island, N.Z.         

 

An unusually larger M 5.3 also occurred today in the Aegean Sea at a high latitude. NEIC reported this earthquake of M 5.3 in the Aegean Sea, Greece  was felt with intensity IV-VI in the area(s) of Greece at Karyai Voria, Sarti, Sikea, Neos Marmaras, Polikhronon, Thasos and II-III in Ouranopolis, Khaniotis, Theologos and Kalwai. A foreshock of M 4.5 hit the same area and was felt with intensity III in Sarti, Greece and in Bulgaria at Sofia and Bozuriste.  It occurred within minutes of local solar midnight and was probably promoted by tidal and geomagnetic effects, both of which are maximized near this hour. This is the latest in a moderate regional activation which has in recent days included moderate events in Crete, Turkey and Albania. It is the strongest earthquake within about 200 km of today's epicenter since an M 5.3 on July 19, 2019 but the last event in the are with greater magnitude was an M 6.9 on May 24, 2014. Forecasts 127497 and 127417 had expected this activity was likely around September 25-26. This epicenter is at 102 degrees from the Banda Sea quake of M 6.8 on August 21 and from the Oaxaca, Mexico event of M 7.4 of June 23 and may have been promoted by concentrated energy from those sources.

 

O: 26SEP2020 22:50:24  40.0N   24.3E Mw=5.3  EMSC   AEGEAN SEA

O: 26SEP2020 23:09:21  40.0N   24.3E mb=4.3  EMSC   AEGEAN SEA

O: 26SEP2020 18:39:18  39.9N   24.3E ML=4.4  EMSC   AEGEAN SEA                    

P: 25SEP2020 127497    40.0N   20.0E 3.0-5.2 AACAA  Romania/NW Turkey          

P: 26SEP2020 127417    34.0N   24.0E 3.0-4.5 ACAAA  Crete                      

 

The strongest earthquake in the U.S. or Canada today occurred at the high latitude of the Fox Islands of the Aleutians, Alaska with M 5.8. It was followed by an aftershock of M 4.4 but was not reported felt in this remote area.

This is the strongest earthquake in the Fox Islands within about 200 km of this epicenter since August 16, 2020 and prior to that an M 5.8 on October 25, 2019. The last such event of larger magnitude than M 5.8 in this area was an M 5.9 on August 25, 2018. The last of M>=6 was an M 6.9 on July 27, 2015.  Forecast 127514 had expected today's event was likely within about 100 km  around September 25.

 

O: 27SEP2020 06:36:08  51.8N  169.7W mb=4.4  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

O: 27SEP2020 04:12:16  51.9N  169.8W Mw=5.8  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 25SEP2020 127514    52.4N  169.4W 3.5-4.9 AAAAA  Fox Islands, Aleutians     

 

MODERATE QUAKES SHAKE CENTRAL ASIA IN TURKMENISTAN AND KASHMIR, INDIA

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 25, 2020

 

Moderate seismicity shook several areas of central Asia today with an M 5.3 in Turkmenistan and several events including an M 5.3 in Kashmir and Jammu, India. Moderate earthquakes of M 4.5-5.0 also occurred in central Asia today in Pakistan, southern China and Hindu Kush, Afghanistan. This may be related to the strong geomagnetic storm still in progress. This storm is described in this summary as:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 20.  High latitude geomagnetic field also saw active conditions with AP 29. This is the strongest geomagnetic disturbance since August 31-September 1 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 25-26, 2020)

 

Today's solar activity included a solar flare of C1.0, the strongest recorded by SEC since an  C2.0 on August 15, 2020 and an C1.5 on August 8, 2020. This could enable higher seismicity in the next couple of days due to solar flare effects (SFE).

 

The strongest earthquake in the world today was an M 5.2-5.3 in Turkmenistan. It was felt with intensity II-III in northern Iran at Gonbad-e, Kavus and Sherwan, Khorasan, Shamali. An M 4.7 regional aftershock followed about 200 km northwest of today's M 5.2  of the mainshock and was felt with intensity IV in Balkanabat, Balka, Turkmenistan. The last earthquake of M>=5.2 within about 200 km of the event of M 5.2 today occurred as an M 5.9 on August 22, 2000. An M 7.0 followed at the epicenter of today's aftershocks on December 6, 2008. Forecasts 127431 and 127474 had expected today's activity at the end of September in this area.

 

O: 26SEP2020 05:46:55  38.2N   56.1E Mw=5.2  EMSC   TURKMENISTAN                 

P: 30SEP2020 127431    37.0N   55.0E 3.8-5.4 BBAAA  No. Iran                   

 

O: 26SEP2020 07:00:19  39.6N   54.6E mb=4.7  EMSC   TURKMENISTAN                 

P: 28SEP2020 127474    40.0N   52.0E 4.0-5.5 AABAA  Kazakhstan                 

 

An earthquake of M 5.3 also occurred today in the Kashmir and Jammu region of India near the Pakistan border. It was reported felt with intensity V in the region of Leh, India. This is the strongest earthquake within about 200 km of this epicenter since an M 5.4 and 5.3 on October 20-21, 2013 and is an unusual epicenter for moderate seismicity. Forecast 127434 had expected today's activity within about 75 km was likely around September 30. This epicenter is at 102 degrees from the strong M 6.8 in the Central Mid-Atlantic of September 18 and was probably promoted by energy from that source.

 

O: 25SEP2020 10:57:13  34.3N   78.3E Mw=5.3  EMSC   KASHMIR-XINJIANG BORDER REGION

O: 25SEP2020 10:57:13  34.3N   78.2E Mw=5.3  ANSS   KASHMIR-XINJIANG BORDER REGION

P: 30SEP2020 127434    35.0N   78.0E 3.8-5.4 BAAAA  Northern India             

 

An M 5.1 also occurred in the Izu Islands of Japan south of Tokyo today.

NEIC reported this earthquake of M 5.1 in the Izu Islands, Japan  was felt with intensity II-III in the area(s) of Japan at Tokyo. This was probably promoted by stresses from Tropical Storm Dolphin which passed over this epicenter over the past two days. 

 

"TS Dolphin (14W) continued today in the area west of the Izu Islands, Japan with winds up to 45 kts. It is expected to track to the north and to turn to the east avoiding the Island of Honshu. Enhanced seismicity may occur, but is not expected to be strong in the region of Honshu, Japan." (September 24-25, 2020)

 

The last earthquake of M>=5.1 in the Izu Islands within about 200 km of today's event was an M 5.7 on July 29, 2019. Forecast 127415 had expected today's event was likely in this area around September 26. This epicenter is at 144 degrees from the M 6.8 in the Central Atlantic of September 18 and was probably promoted from that source.

 

O: 25SEP2020 16:46:46  33.2N  139.7E mb=5.1  EMSC   IZU ISLANDS, JAPAN REGION    

P: 26SEP2020 127415    34.0N  139.0E 3.5-5.0 AAAAA  Central/So. Honshu Japan   

 

Seismicity at high latitudes also continued today with the geomagnetic storm. High AP indices at high latitudes and the continuance of this storm over the next several days is likely to lead to further and stronger activity at high latitudes. These include area of Alaska, Kamchatka and northern Europe in the north and areas south of Africa and South America in the south. The most active area was north of Iceland where a series of earthquakes began near local solar midnight with an M 4.1 and also included events of M 4.2 and 3.9 in the aftershock sequence.  A similar sequence in this region of Iceland followed earthquakes up to M 6.0 on June 20-21 about 100 km southwest of today's events. Forecast 127539 had expected today's activity in this area was likely around September 25, 2020. Today's activity in Iceland is at 103 degrees from Atacama Chile where an M 6.8 occurred on September 1 and a similar distance from the M 6.8 in Sumatra of August 18 and may have been enhanced by energy from those sources. Seismic energy is concentrated on the surface of the earth at distances of 101-104 degrees from strong events and can help trigger additional seismicity at those distances.

 

 

O: 26SEP2020 02:47:12  66.6N   17.8W ML=4.1  EMSC   ICELAND REGION

O: 26SEP2020 02:59:23  66.6N   17.8W ML=3.3  EMSC   ICELAND REGION

O: 26SEP2020 03:32:03  66.6N   17.8W ML=3.9  EMSC   ICELAND REGION

O: 26SEP2020 03:33:56  66.6N   17.8W ML=4.2  EMSC   ICELAND REGION

O: 26SEP2020 03:35:47  66.6N   17.8W ML=3.7  EMSC   ICELAND REGION

O: 25SEP2020 11:33:27  66.6N   17.8W ML=3.3  EMSC   ICELAND REGION               

P: 25SEP2020 127539    66.0N   17.0W 3.0-4.9 AAAAA  Iceland area               

 

An M 3.5-3.7 in Southern California today was widely felt and was the strongest earthquake in the U.S. or Canada today. NEIC reported it as felt with intensity II-III in Desert Hot Springs, Thousand Palms, Cathedral City, Palm Springs, Rancho Mirage, Palm Desert, White Water, Joshua Tree and Morongo Valley, California. A foreshock of M 3.0 was felt with intensity II-III in Desert Hot Springs, Thousand Palms, Palm Springs, Yucca Valley, and Norco. The M 3.7 followed a foreshock of M 2.9. The last event within about 100 km of this epicenter with M>=3.7 was activity including events of M 4.9, 3.8 and 3.7 on April 4, 2020.  Forecast 127443 had expected today's activity was likely in this area around September 26.

 

O: 25SEP2020 17:10:10  34.0N  116.4W ML=3.5  EMSC   SOUTHERN CALIFORNIA

O: 25SEP2020 17:10:11  33.9N  116.4W ML=3.7  ANSS   SOUTHERN CALIFORNIA

O: 25SEP2020 17:07:47  33.9N  116.4W ML=2.9  EMSC   SOUTHERN CALIFORNIA          

P: 26SEP2020 127443    33.9N  116.9W 2.5-4.4 AAAAA  So. California             

 

An unusually large M 4.5 hit the active region of Mayotte today. It was not reported felt in this area. This area became active in May, 2018 and has seen many moderate quakes since that time. The last within about 200 km of today's  event occurred on March 21, 2020 with the Spring equinox with M 5.0. The only other such events in the area in the past year of M>=4.5 occurred on January 1-2 with M 4.6 and 5.1. Forecast 127554 had expected today's event was likely within about 100 km around September 26.

 

O: 25SEP2020 08:26:08  12.9S   45.6E ML=4.5  EMSC   MAYOTTE REGION               

P: 26SEP2020 127554    12.0S   45.0E 3.0-4.4 AAAAA  Madagascar area            

 

ACTIVE CONDITIONS IN HIGH LATITUDE GEOMAGNETIC FIELD AND SEISMICITY

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 24, 2020

 

The strongest seismicity in the world today occurred at high latitudes in the area of the South Atlantic Ocean. This included an M 5.3 in the Scotia Sea and an M 5.1 in the South Sandwich Islands. This activity was probably promoted by a strong geomagnetic storm at high latitudes as noted in previous issues of this summary:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 19.  High latitude geomagnetic field also saw active conditions with AP 48. This is the strongest geomagnetic disturbance since August 31-September 1 and is expected to continue for several more days. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 24-25, 2020)

 

The M 5.3 in the Scotia Sea was the strongest in that region within about 300 km of this epicenter since an M 5.4 on March 9, 2016, the only other such event in at least 30 years. Today's event was not reported felt in this remote area. Forecast 127596 had expected a moderate quake in this area around September 28.

 

O: 25SEP2020 03:56:01  57.2S   40.7W mb=5.3  EMSC   SCOTIA SEA                   

P: 28SEP2020 127596    60.0S   44.0W 3.0-6.0 BBBAA  So. So. America            

 

The M 5.1 in the southern South Sandwich Islands is the strongest in that region within about 150 km since an M 5.1 on August 16, 2020. These follow an M 6.3 on July 26  about 100 km to the southeast of today's epicenter which occurred on July 26, 2020. Forecast 127595 had expected today's earthquake within about 100 km of this epicenter was likely around September 28.

 

O: 25SEP2020 03:54:56  60.6S   26.6W mb=5.1  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 28SEP2020 127595    60.0S   26.0W 4.0-6.0 BAAAA  So. Sandwich Islands       

 

An earthquake of M 5.3 also occurred today in the Gulf of California and was followed by aftershocks of M 4.5 and 3.7. It was likely promoted by stresses from Tropical Storm Lowell which is currently south of the Gulf of California and was noted in previous issues of this summary as:

 

"Tropical Storm Lowell continued south of Baja California, Mexico today with winds up to 50 kts. This system is currently  expected to track to the northwest but not to impact regional seismicity at this time." (September 22-23, 2020)

 

This epicenter is north of recent activity in the Gulf of California and is the strongest within about 100 km of this epicenter since an M  6.3 on January 19, 2018 about 100 km southeast of today's epicenter. The only other such event in this region in the past 10 years was an M 5.3-5.4 on April 26, 2011. Forecast 127389 had expected moderate activity in the Gulf of California to the southeast around September 24.

 

NEIC reported this earthquake of M 5.3 in the Gulf of California  was felt with intensity II-III in the area(s) of the Gulf of California at Mulega, Baja California, Mexico.

 

O: 24SEP2020 23:01:29  27.1N  111.4W Mw=5.3  EMSC   GULF OF CALIFORNIA

O: 25SEP2020 00:37:56  27.8N  111.7W ML=3.7  EMSC   GULF OF CALIFORNIA

O: 24SEP2020 23:06:41  27.0N  111.3W mb=4.5  EMSC   GULF OF CALIFORNIA           

P: 24SEP2020 127389    24.0N  109.0W 3.5-5.3 ACBAA  Gulf of California         

 

The strongest earthquakes in the U.S. or Canada today also occurred at high latitudes. These events of M 4.9 occurred in the Rat Islands, Aleutians and in the Alaska Peninsula as an aftershock of the July 22, 2020 M 7.8 in the Alaska Peninsula. This is the strongest aftershock in the Alaska Peninsula since an M 5.0 on August 20 and the largest within about 100 km of the mainshock since an M 5.2 on August 9, 2020. Forecast 127507 had expected this earthquake was likely around September 24.

 

O: 25SEP2020 05:57:57  55.2N  157.9W Mw=4.9  EMSC   ALASKA PENINSULA             

P: 24SEP2020 127507    54.8N  158.7W 3.5-5.5 AAAAA  Alaska Peninsula           

 

The M 4.9 in the Rat Islands is the strongest in that region since an M 4.9 on February 13, 2020 and an M 5.3 on February 4, 2020. Today's event was not reported felt. Forecasts 127245 and 127523 had expected today's activity in mid to late September.

 

O: 24SEP2020 19:23:15  51.7N  177.9E mb=4.9  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 17SEP2020 127245    51.0N  177.0E 4.0-5.8 CAAAA  Rat Islands                

P: 29SEP2020 127523    50.0N  178.0E 4.0-6.1 BBAAA  Rat Islands                

 

 

STRONG SEISMICITY CONTINUES NEAR EQUATOR IN ATLANTIC

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 23, 2020

 

The strongest earthquake in the world today was an M 5.7 in the central mid-Atlantic. It was not felt in the area. This epicenter is at the equator, an area which in the past several days has shown strongly enhanced seismicity in Sumatra, the Central mid-Atlantic, the Galapagos Islands, the northern East Pacific Rise, among others, as noted in previous issues as:

 

"The most active zone of seismicity in the world today was the northern equatorial latitude band between about 0 and 20 degrees north. This band is especially active at this time of year because of strong meteorological ocean storms  (hurricanes and typhoons) which occur in these latitudes and are maximum in September. In the western Hemisphere this included continuing enhanced seismicity in eastern and central Mexico and in the Dominican Republic. The strongest earthquake of the day in this area, however was an M 5.4 in the Galapagos Islands area near the equator. Today is the first day of autumn when the sun reaches its zenith over equator. As has been suggested in this summary in prior issues, this can enhance vertical seismicity in latitudes where the sun reaches its zenith (is directly overhead at local solar noon). In this case that is the equator." (September 20-21, 2020)

 

Similar events of M 5.9 and 6.1 occurred near today's epicenter in the central east Pacific on March 22, 2020 - the first such activity in the area since September 11, 2013. Note that the event in March occurred, like today's on the equinox (in this case, the first day of Spring) while today's event is on the first day of Autumn." (September 21-22, 2020)

 

Today's event may also have been promoted by the occurrence of a geomagnetic storm today, the largest since early September as noted in this summary:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 11.  High latitude geomagnetic field also saw active conditions with AP 29. Geomagnetic disturbances of this level can help promote enhanced seismicity at high latitudes and near the geomagnetic equator. Moderate to moderately strong events in these areas are likely in the next several days." (September 23, 2020)

 

The last earthquake within about 200 km of today's epicenter with M>=5.7 was an M 5.9 on July 23, 2018 and prior to that an M 7.1 on August 29,, 2016. Today's event occurred within about half an hour of local solar midnight and was also likely promoted by strong tidal stresses which maximize at this time. Forecast 127068 had expected today's event was likely in the central Mid-Atlantic within about 100 km of today's epicenter around September 19.

 

O: 24SEP2020 00:27:49   0.2S   18.8W Mw=5.7  EMSC   CENTRAL MID-ATLANTIC RIDGE   

O: 24SEP2020 01:01:28   0.3S   19.1W mb=4.8  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P: 19SEP2020 127068     1.0S   20.0W 4.0-5.7 BAAAA  Central Mid-Atlantic       

 

An M 4.5 in the Greenland Sea followed the geomagnetic storm today. This is the strongest earthquake within about 400 km of this epicenter in the Greenland Sea since an M 4.6 on March 11 and an M 4.9 on October 29, 2019. Forecast 127546  had expected today's activity was likely within about 100 km of this epicenter around September 30. This event is at 103 degrees from the Banda M 7.0 of August 21 and was probably promoted by energy from that source.

 

O: 24SEP2020 04:44:56  79.6N    3.1E mb=4.5  EMSC   GREENLAND SEA                

P: 30SEP2020 127546    79.0N    7.0E 4.0-5.4 CAAAA  Arctic Ocean Region        

 

Unusual earthquakes occurred in eastern Europe today in Greece with M 4.6 and in Albania with M 4.3. The earthquake of M 4.6 in Greece is the strongest within about 150 km of this epicenter on March 21, 2020. A similar M 4.6 hit south of today's event on July 25, 2020 with M 4.7. Forecast 127428 expected today's event was likely around September 26.

 

NEIC reported this earthquake of M 4.6 in Greece  was felt with intensity II-III in the area(s) of Greece at Karia and Nidrion, Levkas and Vasilika, Trikala.  This event, like that in the Greenland Sea today, is at 103 degrees from the Banda M 7.0 of August 21 and was probably promoted by energy from that source.

 

O: 24SEP2020 05:10:19  38.8N   20.5E mb=4.6  EMSC   GREECE                       

P: 25SEP2020 127428    38.0N   21.0E 3.0-4.5 AAAAA  No. Greece                 

 

The earthquake in Albania of M 4.3 is the strongest within about 150 km of this epicenter in Albania since an M 4.2 on September 12. The last of larger magnitude in the area was an M 4.5 on July 26, 2020. Forecast 127497 had expected today's event in this area was likely around September 25.

 

NEIC reported this earthquake of M 4.3 in  Albania was felt with intensity II-III in the area(s) of Albania at Tirana and Vlore.  This event, like that in the Greenland Sea today, is at 103 degrees from the Banda M 7.0 of August 21 and was probably promoted by energy from that source.

 

O: 23SEP2020 23:25:10  41.0N   19.8E mb=4.3  EMSC   ALBANIA                      

P: 25SEP2020 127497    40.0N   20.0E 3.0-5.2 AAAAA  Romania/NW Turkey          

 

An M 5.3 in northern Mindanao, Philippines today was followed by a series of moderate aftershocks. It occurred within about an hour of local solar noon and may have been enhanced by strong tidal stresses which maximize at this hour as well as by effects from the geomagnetic storm today. It was near sub-solar at the time of the event. This appears to be an aftershock of the M 5.8 which occurred about 50 km southwest of today's epicenter on September 20, 2020. A similar M 5.8 hit he area on July 27, 2020. Forecast 127368 had expected today's event within about 50 km was likely around September 25.

 

NEIC reported this earthquake of M 5.3 in northern Mindanao  was felt with intensity II-III in the area(s) of northern Mindanao, Philippines at Gamut iTago and Alubijid, Caraga, Philippines. Today's event is located at the fifth node (72 degrees) from the M 7.8 in the Alaska Peninsula of July 22 and may have been promoted by energy from that source.

 

O: 23SEP2020 10:21:48   9.3N  126.8E ML=4.2  EMSC   MINDANAO, PHILIPPINES        

O: 23SEP2020 22:19:43   9.3N  127.0E mb=4.7  EMSC   PHILIPPINE ISLANDS REGION    

O: 24SEP2020 02:26:00   9.5N  126.9E Mw=5.3  EMSC   MINDANAO, PHILIPPINES        

O: 23SEP2020 23:32:56  10.1N  126.4E ML=4.0  EMSC   PHILIPPINE ISLANDS REGION    

P: 25SEP2020 127368    10.0N  127.0E 3.5-4.9 AAAAA  Luzon, Philippines         

 

SOUTH SHETLAND ISLANDS SWARM CONTINUES

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 22, 2020

 

The strongest earthquakes in the world today were two events of M 5.2 in the

South Shetland Islands between South America an Antarctica. These events were not reported felt in this remote area. This continues a series of earthquakes at this epicenter which began with an M 5.0 on August 29 and peaked with an M 5.4 on September 1. The most recent was an M 5.3 on September 19. Forecasts 127596 and 127314 had expected moderate seismicity in the South Shetland Islands was likely between September 17 and 24. This activity is at 141 degrees from the M 7.8 in the Alaska Peninsula of July 22 and may have been promoted by energy from that source.

 

O: 22SEP2020 23:44:13  62.3S   58.3W Mw=5.2  EMSC   SOUTH SHETLAND ISLANDS

O: 22SEP2020 23:53:48  62.3S   58.4W Mw=5.2  EMSC   SOUTH SHETLAND ISLANDS

O: 22SEP2020 08:25:21  62.3S   58.0W mb=4.9  EMSC   SOUTH SHETLAND ISLANDS       

P: 17SEP2020 127314    56.0S   55.0W 4.0-5.8 BCBAA  Southern  Ocean            

P: 24SEP2020 127596    56.0S   54.0W 3.0-6.0 ACCAA  South Shetland Is.         

 

The strongest earthquake in the U.S. or Canada today was an M 3.7 near Newfoundland. It was not reported felt in this remote area. The last earthquake within about 300 km of this epicenter with M>=3.7 occurred on February 3, 2020 with M 4.3, the only such event listed by NEIC in the past 30 years.  Forecast 127250 had expected this region would see light to moderate seismicity in

mid-September. Today's earthquake occurred as Tropical Storm Teddy was passing near this epicenter off Labrador. This summary had previously noted the likely effects of Teddy on this region as:

 

"Hurricane Teddy continued today in the Atlantic east of Virginia with winds up to 85 kts. It is expected to track to the north and west over the next week. Some enhanced seismicity may occur in the eastern U.S. and Canada when this storm makes landfall near Nova Scotia around  September 23-24 where some seismicity may be promoted." (September 21-22, 2020)

 

O: 22SEP2020 05:52:09  57.5N   59.6W MB=3.7  ECAN Nutak, NL                      

P: 14SEP2020 127250    67.0N   54.0W 2.5-4.1 CCCAA  Baffin/Davis Strait, Canada

 

An M 4.1 also occurred west of Washington State today. It was not reported felt along the coast line. The last earthquake within about 150 km of this epicenter with M>=4.1 occurred on December 1, 2019 with M 4.1 and prior to that as an M 4.5 on October 11, 2017.  Forecast 127225 had expected today's event about 100 km to the north was likely around September 19.

 

O: 22SEP2020 23:25:49  47.4N  129.0W mb=4.1  EMSC   OFF COAST OF WASHINGTON      

P: 19SEP2020 127225    48.3N  128.5W 2.8-5.0 BAAAA  Vancouver Island area      

 

A swarm of earthquake occurred today at the southeastern most point in Puerto Rico. NEIC reported these earthquakes of M 3.0-4.0 in  Puerto Rico were felt with intensity II-III in the area(s) of Puerto Rico at Lajas, San German, Mayaguez, Cabo Rojo. These epicenters are west of the aftershock group in southern Puerto Rico following the M 6.5 in January, 2020 and do not appear to be aftershocks of that event. The last earthquake this far to the west in southern Puerto Rico of M>=3.4 occurred in February 22, 2016. Forecast 127380 had expected today's activity was likely within about 20 km of these epicenters around September 23.

 

O: 22SEP2020 10:41:58  17.9N   66.6W Md=3.1  EMSC   PUERTO RICO REGION

O: 22SEP2020 10:41:58  17.9N   66.6W Md=3.1  EMSC   PUERTO RICO REGION

O: 22SEP2020 16:27:32  17.9N   66.8W Md=3.0  EMSC   PUERTO RICO REGION

O: 22SEP2020 23:44:23  17.9N   67.1W ML=3.4  EMSC   PUERTO RICO REGION

O: 23SEP2020 01:08:27  17.9N   67.1W ML=3.4  EMSC   PUERTO RICO REGION

O: 23SEP2020 02:05:27  17.9N   67.1W ML=3.1  EMSC   PUERTO RICO REGION

O: 23SEP2020 05:30:44  17.9N   67.1W Md=3.4  EMSC   PUERTO RICO REGION

O: 22SEP2020 09:08:48  17.9N   66.8W Md=3.1  EMSC   PUERTO RICO REGION           

O: 22SEP2020 23:26:50  18.0N   67.1W MD=3.0  EMSC   PUERTO RICO REGION           

P: 23SEP2020 127380    18.0N   67.0W 3.4-5.0 AAAAA  Puerto Rico                

 

 

 

 

STRONG SEISMICITY CONTINUES NEAR THE EQUATOR

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 21, 2020

 

The strongest earthquake in the world today was an M 5.9 in the central East Pacific Rise. It was not reported felt in this remote area. This is part of a pattern of seismicity emphasizing strong activity near the equator.  In the previous issue of this report it was noted that areas near the equator were at particular risk for enhanced seismicity at this time as:

 

"The most active zone of seismicity in the world today was the northern equatorial latitude band between about 0 and 20 degrees north. This band is especially active at this time of year because of strong meteorlogical ocean storms  (hurricanes and typhoons) which occur in these latitudes and are maximum in September. In the western Hemisphere this included continuing enhanced seismicity in eastern and central Mexico and in the Dominican Republic. The strongest earthquake of the day in this area, however was an M 5.4 in the Galapagos Islands area near the equator. Today is the first day of autumn when the sun reaches its zenith over equator. As has been suggested in this summary in prior issues, this can enhance vertical seismicity in latitudes where the sun reaches its zenith (is directly overhead at local solar noon). In this case that is the equator." (September 20-21, 2020)

 

A similar event of M 6.1 occurred near today's epicenter in the central east Pacific on March 22, 2020 - the first such activity in the area since September 11, 2013. Note that the event in March occurred, like today's on the equinox (in this case, the first day of Spring) while today's event is on the first day of Autumn. Forecast 127077 had expected today's activity within about 50 km was likely around September 18.

 

O: 21SEP2020 13:37:14   4.0S  104.4W Mw=5.9  EMSC   CENTRAL EAST PACIFIC RISE

O: 21SEP2020 12:27:56   4.1S  104.3W mb=4.7  EMSC   CENTRAL EAST PACIFIC RISE

O: 21SEP2020 12:06:23   4.0S  104.3W mb=4.7  EMSC   CENTRAL EAST PACIFIC RISE    

P: 18SEP2020 127077     4.0S  104.0W 4.0-5.8 BAAAA  No. East Pacific Rise      

 

A moderately large earthquake of M 5.5 shook the region near Lake Baykal today. It was reported by NEIC to have been felt with maximum intensity VII in Irkutsk, Russia at Shelekhov; IV in Baykalsk, Irkutsk, Angarsk, Kyren, Ulan-Ude, Burjatija; Selenginsk, Naushki and in Zuunharaa Selenge, Mongolia. NEIC reported an aftershock of M 4.6 in Irkutsk, Russia  was felt with intensity II-III in the area(s) of Irkutsk, Russia at Angarsk (V) and Irkutsk. The M 5.5 may have been promoted by high tidal stresses as it occurred within  about 30 minutes of local solar midnight when these stresses are maximized. The last earthquake in the Lake Baykal region within about 300 km of today's epicenter was an M 6.3 on August 27, 2008, the strongest earthquake in the past 30 years in this region. Forecast 127246 had expected today's event in  this region was likely around September 17. These events are at the seventh node (52 degrees) from the Alaska Peninsula M 7.8 of July 22 and were probably promoted by energy from that source.

 

O: 21SEP2020 18:19:55  51.8N  103.5E mb=4.6  EMSC   LAKE BAYKAL REGION, RUSSIA

O: 21SEP2020 18:04:57  51.8N  103.6E Mw=5.5  EMSC   LAKE BAYKAL REGION, RUSSIA   

P: 17SEP2020 127246    56.0N  110.0E 3.0-4.7 BCCAA  So. Siberia                

 

The strongest earthquakes in the U.S. or Canada today were M 4.2 events in southern Alaska. One of these was an M 4.2 aftershock in the Gulf of Alaska, the other occurred in the Kodiak Island area. The last event of M>=4.2 in the Gulf of Alaska was an M 5.1 on March 20, 2020. Forecast 127260 had expected this activity was likely around September 17.

 

O: 21SEP2020 10:30:02  57.0N  149.4W mb=4.2  EMSC   GULF OF ALASKA               

P: 17SEP2020 127260    55.0N  149.0W 3.0-4.8 BBAAA  Northern Alaska            

 

The event in the Kodiak area of Alaska is the strongest in the Kodiak area since an M 5.1 on July 8, 2020. Forecast 127253 had been expected in mid-September. NEIC reported this earthquake of M 4.0-4.2 in Kodiak, Alaska  was felt with intensity II-III in the area(s) of Kodiak, Alaska. This epicenter is near 103 degrees from the M 6.8 in the Central Atlantic of September 18 and was probably enhanced by energy from that source.

 

O: 21SEP2020 18:55:29  57.8N  153.6W ML=4.2  EMSC   KODIAK ISLAND REGION, ALASKA 

P: 15SEP2020 127253    60.2N  153.2W 3.2-5.1 CCAAA  Central Alaska             

 

A swarm of earthquakes occurred in the Mammoth Lakes area of California today. The strongest of these occurred with M 3.0. The last event in the Mammoth Lakes area of M>=3.0 was an M 3.2 on  August 1, 2020. Forecast 127142 had expected today's activity around September 17.

 

NEIC reported this earthquake of M 3.0 in Mammoth Lakes, California  was felt with intensity II-III in the area(s) of Mammoth Lakes, California. This activity is at the fourth node (90 degrees) from the earthquake of M 6.7 in the Mid-Atlantic of September 18 and at 90 degrees from the M 7.4 in the Kermadec  Islands of June 18, 2020 and was probably promoted by energy from these sources.

 

O: 21SEP2020 21:06:32  37.6N  118.9W Md=2.1  EMSC   LONG VALLEY AREA, CALIFORNIA

O: 22SEP2020 01:13:40  37.6N  118.9W Md=2.7  EMSC   LONG VALLEY AREA, CALIFORNIA

O: 22SEP2020 01:14:55  37.7N  119.0W ML=2.5  EMSC   LONG VALLEY AREA, CALIFORNIA

O: 22SEP2020 01:14:55  37.6N  118.9W ML=3.0  ANSS   LONG VALLEY AREA, CALIFORNIA

O: 21SEP2020 15:51:35  37.9N  119.1W ml=2.4  EMSC   CENTRAL CALIFORNIA

O: 21SEP2020 18:31:58  37.5N  118.6W Md=2.8  EMSC   CENTRAL CALIFORNIA           

P: 17SEP2020 127142    37.9N  118.2W 2.5-4.4 BAAAA  California/Nevada area     

 

MODERATE SEISMICITY IN NORTHERN TROPICAL LATITIDES

  

EARTHQUAKE SUMMARY FOR SEPTEMBER 20, 2020

 

The most active zone of seismicity in the world today was the northern equatorial latitude band between about 0 and 20 degrees north. This band is especially active at this time of year because of strong meteorological ocean storms  (hurricanes and typhoons) which occur in these latitudes and are maximum in September. In the western Hemisphere this included continuing enhanced seismicity in eastern and central Mexico and in the Dominican Republic. The strongest earthquake of the day in this area, however was an M 5.4 in the Galapagos Islands area near the equator. Today is the first day of autumn when the sun reaches its zenith over equator. As has been suggested in this summary in prior issues, this can enhance vertical seismicity in latitudes where the sun reaches its zenith (is directly overhead at local solar noon). In this case that is the equator. The earthquake in the Galapagos occurred near local solar midnight, a time when such tidal triggering may be maximized. It was not reported felt but is the strongest event in the Galapagos within about 200 km of this epicenter since an M 5.6 exactly two years ago on September 21, 2018, also the autumn equinox. That event occurred near the epicenter of today's quake. The largest event in the region in the past 30 years was an M 5.8 on March 15, 2009. Forecast 127058 had expected today's event in the Galapagos area was likely in mid-September. This event and the M 5.8 in northern Mindanao, today are located at the fifth node (72-73 degrees) from the M 7.8 in the Alaska Peninsula of July 22, 2020, the last major global earthquake, and may have been promoted by energy from that source. Another active area at the fifth node from Alaska that was active today was the Dominican Republic.

 

O: 20SEP2020 09:50:22   2.4N   95.5W mb=4.7  EMSC   GALAPAGOS ISLANDS REGION

O: 20SEP2020 09:42:15   2.6N   95.3W Mw=5.4  EMSC   GALAPAGOS ISLANDS REGION     

P: 14SEP2020 127058     2.0N   91.0W 3.5-5.0 CACAA  Galapagos Islands          

 

In the eastern hemisphere, seismicity in the band 0-20 north latitude included a series of moderate to moderately strong earthquake in the Philippines. The strongest of these, and the strongest earthquake in the world today was an M 5.8-5.9 in the region of northern Mindanao. It was followed by events of M 5.0-5.4 in southern Mindanao and northern Luzon. The M 5.8 in Northern Mindanao was the strongest within about 200 km of that epicenter since an M 5.8 on July 27, 2020 and an M 5.8 on July 12, 2019. The last of larger magnitude in this area was an M 6.0 on March 8, 2019. Forecast 127055 had expected this event in this area was likely around September 19. 

 

PHIVOLCS reported this earthquake of M 5.7 in northern Mindanao, Philippines  was felt with intensity IV at Bayabas, Surigao Del Sur; III inj Tago, Surigao Del Sur, Claver, Surigao Del Norte; II in Tandag City, Carmen and Cagwait,Surigao del Sur and I in Hinatuan, Surigao Del Sur. PHIVOLCS reported the aftershock of M 5.3 in Mindanao, Philippines  was felt with intensity III in General Santos City; Alabel, Sarangani; II in Mati City; Glan and Malapatan, Sarangani; Don Marcelino, Davao Occidental, Kiblawan and Sta. Cruz, Davao del Sur.

 

 

O: 20SEP2020 23:14:03   9.3N  127.1E ML=4.1  EMSC   PHILIPPINE ISLANDS REGION

O: 21SEP2020 06:35:29   9.3N  127.1E ML=4.0  EMSC   PHILIPPINE ISLANDS REGION

O: 20SEP2020 22:21:48   9.4N  126.9E Mw=5.3  EMSC   MINDANAO, PHILIPPINES

O: 21SEP2020 04:28:58   9.4N  127.2E ML=4.0  EMSC   PHILIPPINE ISLANDS REGION

O: 20SEP2020 22:13:14   9.2N  126.7E Mw=5.8  EMSC   MINDANAO, PHILIPPINES        

P: 19SEP2020 127055     8.0N  125.0E 4.0-5.4 ABBAA  Central Philippines        

 

NEIC reported the earthquake of M 5.0 in Mindanao, Philippines  was felt with intensity II-III in the area(s) of Mindanao, Philippines at Buayan. Forecast 127059 had expected this event was likely around September 20.

 

O: 20SEP2020 13:28:27   6.7N  125.6E Mw=5.0  EMSC   MINDANAO, PHILIPPINES        

P: 20SEP2020 127059     6.0N  127.0E 4.0-5.5 AABAA  Halmahera                  

 

NEIC reported the earthquake of M 4.7 in Northern Philippines  was felt with intensity II-III in the area(s) of Northern Philippines at Claveria, Cagayan Valley. PHIVOLCS reported this earthquake of M 4.9 in Northern Philippines  was felt with intensity IV at Claveria and Sanchez-Mira, Cagayan; Calanasan, Apayao, Pagudpud, Bangui and Adams, Ilocos Norte; III in Pasuquin, Bacarra and Burgos, Ilocos Norte and II in Pamplona, Cagayan, Vintar , Ilocos, Norte. Forecasts 127107 and 127135 had expected this acdtivity was likely in mid-September. This epicenter is at 143 degrees from the Atlantic M 6.7 of September 18 and may have been enhanced by energy from that source.

 

O: 20SEP2020 17:47:19  18.6N  121.0E mb=4.7  EMSC   LUZON, PHILIPPINES           

P: 15SEP2020 127107    19.0N  122.0E 3.5-4.9 BAAAA  Luzon, Philippines         

P: 19SEP2020 127135    20.0N  121.0E 4.0-5.5 ABAAA  Taiwan                     

 

An unusually large M 5.3 also shook regions of central Turkey today. NEIC reported this earthquake of M 5.3 in  Central Turkey was felt with intensity II-III in the area(s) of Central Turkey at Aksaray (IV), Adana and Ankara. This is the strongest earthquake within about 300 km of this epicenter since an M 5.6 northwest of this on December 26, 2007. No such quakes have been recorded within 200 km of today's epicenter in the past 30 years. Forecast 127186 had expected today's epicenter to be active in this area of Turkey within about 100 km of today's event  was likely around September 18.

 

 

O: 20SEP2020 19:08:06  38.0N   34.0E Mw=5.3  EMSC   CENTRAL TURKEY               

O: 21SEP2020 03:37:31  38.1N   34.0E ML=4.0  EMSC   CENTRAL TURKEY               

P: 18SEP2020 127186    37.0N   34.0E 3.5-5.1 AAAAA  Turkey                     

 

 

 

STRONG QUAKE IN MID-INDIAN RIDGE TRIGGERED FROM MID-ATLANTIC

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 19, 2020

 

The strongest earthquake in the world today was an M 5.9 in the Mid-Indian Ridge. It was not felt in this remote area. The last earthquake in the mid-Indian Ridge area within about 300 km of this epicenter with M>=5.9 occurred as an M 6.1 on April 12, 2020 and prior to that an M 6.4 on October 4, 2013 and

an M 6.1 on May 7, 2006.  Forecast 127302 had expected today's event within about 100 km of this epicenter was likely around September 20. This epicenter is antipodal to the area of western  Oklahoma/Texas and Colorado where active seismicity occurs. Some enhanced seismicity in this area is possible in the next several days. This epicenter is located at 102-103 degrees from the M 6.7 in the central-mid Atlantic of September 18. Energy from large events concentrates on the surface after internal reflections at this distance from large earthquakes and can help promote seismicity at this distance, as it apparently did in this case.

 

O: 19SEP2020 21:09:32  37.6S   77.9E Mw=5.9  EMSC   MID-INDIAN RIDGE             

P: 20SEP2020 127302    37.0S   79.0E 4.0-5.4 AAAAA  So. Indian Ocean           

 

The strongest earthquake in the U.S. or Canada today was an M 3.9 in the Unimak Island region of Alaska. This is probably a regional aftershock of the M 7.7 in the Alaska Peninsula of July 22, 2020. An earthquake of M 5.6 hit this epicenter on August 13, 2020 but the last of M>=3.9 in the Unimak region was an M 4.5 a month ago on August 23, 2020. Forecast 127248 had expected today's event was likely in the Unimak area around September 17.

 

O: 20SEP2020 02:07:39  53.1N  163.4W mb=3.9  EMSC   UNIMAK ISLAND REGION, ALASKA 

P: 17SEP2020 127248    54.6N  163.6W 3.5-5.3 BAAAA  Unimak Islands, Aleutians  

 

 

STRONG EARTHQUAKE CONTINUES ACTIVE PERIOD IN MID-ATLANTIC

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 18, 2020

 

The strongest earthquake in the world today was an M 6.7 in the Central Mid-Atlantic, continuing strong seismic enhancement in this region. It was probably promoted by stresses associated with a series of tropical storms which have passed near this epicenter in the past several days. The most recent of these was TS Winfred which is discussed in this summary as:

 

"TS Winfred formed today over the western Atlantic with winds up to 40 kts. It is expected to track to the west over the several days. Some seismic enhancement is possible at this time in the central mid-Atlantic Ridge as Winfred passes over. An earthquake of M 6.7 in the central mid-Atlantic today may have been promoted by stresses from this storm." (September 18, 2020)

 

This earthquake was also probably promoted by strong tidal stresses associated with the new moon as it occurred in the longitude band where stresses from this alignment were expected to maximize as follows:

 

"The new moon arrived September 17, 2020 at 11:00 UT. Longitudes which were at sub-solar locations (local solar noon) are near 15 East longitude and include western Europe while those anti-solar regions are near 165 West longitude including areas near the International Date Line (IDL) at 180 East longitude such as the Aleutian Islands, Kamchatka and areas of Tonga, Fiji and regions of the southwest Pacific. These areas will probably see enhanced seismicity in the next week. Other areas may also see tidally-promoted seismicity during this time when a set of strong earthquakes is likely especially in the southwestern and northern Pacific rim." (September 15-18, 2020)

 

Strong earthquakes in the mid-Atlantic in the past month have included an M 6.5 about 300 km west of today's event on August 30 and an M 6.6 more than 1000 km to the northwest on September 6, 2020. The last earthquake within about 250 km  of today's event in the central mid-Atlantic with M>=6.7 occurred more than  30 years ago, this being the strongest quake in the area since an M 6.7 on October 7, 1975 - the largest historical event recorded in this region and the only other such event of M>=6.7.

 

Forecast 127053 had expected today's event within about 100 km of the epicenter was likely around September 14. Today's epicenter is located at 51.4 degrees (node 7) from the Atacama, Chile M 7.0 of September 1 and may have been promoted by energy from that source.

 

O: 18SEP2020 21:43:58   0.8N   26.7W Mw=6.7  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P: 14SEP2020 127053     1.0N   28.0W 4.0-5.6 BABAA  Central Mid-Atlantic Ridg  

 

The M 6.7 in the Central Mid-Atlantic followed an M 5.2 near the antipode in Papua, New Guinea. It was reported felt with intensity II-III in New Guinea at Lae, Morobe, Finshhafen and Port Moresby. Forecast 127076 had expected this event was likely within about 100 km in mid-September.

 

O: 18SEP2020 20:59:47   5.6S  147.0E Mw=5.2  EMSC   EASTERN NEW GUINEA REG., P.N.G

P: 13SEP2020 127076     5.0S  148.0E 4.0-5.6 BAAAA  New Ireland                

 

An earthquake of M 5.9 also occurred in the region of Crete, Greece today. NEIC reported it was felt with intensity IV in Greece at Ierapetra, Nea Alikarnassoa and Iraklion and in Iraklion with II-III in Pirgos, Stalis, Gournai, Kato Gouvari, Limin Khersonisou, Khanico tou Kokkini and Aghios. This earthquake may also have been promoted by strong tidal stresses associated with the new moon as it lies near the longitude of maximum stress with that event (see above). This is the strongest earthquake in Crete within about 200 km of this epicenter since an M 6.6 on May 2, 2020 and although it occurred about 100 km northwest of that event, may be a regional aftershock of it. The last such activity within about 100 km of today's epicenter was an M 6.1 and 6.0 on June 15 and 16, 2013. Forecast 127150 had expected this event was likely in Crete between September 18 and 20.

 

O: 18SEP2020 16:28:17  34.8N   25.3E Mw=5.9  EMSC   CRETE, GREECE                

P: 18SEP2020 127150    34.0N   24.0E 3.0-4.6 AAAAA  Crete                      

P: 20SEP2020 127150    34.0N   26.0E 3.0-4.4 AAAAA  Crete                      

 

A moderate earthquake of M 4.5 rocked the Los Angeles, California area today. NEIC reported it was felt with maximum intensity V in the epicentral area including at Rico Rivera, Monterey Park, Rosemead, San Gabriel and IV in Montebello, El Monte, South El Monte, Los Angeles, Whittier. This earthquake occurred within about an hour of local solar midnight and was probably promoted by strong tidal stresses associated with the new moon, as these maximize near this hour. The mainshock was preceded by a group to earthquakes of smaller magnitude in the Los Angeles area to the west. Seismicity in the region had been expected in this summary to be enhanced at this time as noted in the September 9, 2020 summary following a moderate earthquake in New Jersey:

 

"This correlation (between earthquakes in the New Jersey area and southern California) is strongest with moderate starting quakes in the region of Delaware. The area of southern California near Northridge is currently at the 23-year cycles of large quakes in the area. A moderate earthquake in the region west of Los Angeles and north to San Francisco is considered possible in the next four days. At the least, residents should check their earthquake preparedness kits to see if they are ready for a moderate quake at this time." (December 1, 2017, September 9, 2020)

 

Today’s event may also have been affected by slopefall of Hurricane Teddy yesterday as described in previouos issues of this summary:

 

“Hurricane Teddy continued today in the mid-Atlantic with winds up to 90 kts. It is expected to track to the west over the next week. Some enhanced seismicity may occur in the northern Mid-Atlantic ridge area in the next several days. It is expected to reach category 4 hurricane winds by September 20 but will probably remain over the Atlantic and not to threaten landfall. If it tracks further to the west it will make slopefall in about a week. This could promote a moderate to strong earthquake in the western rim of North America” (September 15-17, 2020)

 

 

Today's M 4.5 is at the fourth node (90 degrees) from the earlier event of M 6.7 in the mid-Atlantic and may have been promoted by energy from that source. The M 4.5 is the strongest earthquake in Los Angeles within about 50 km of this epicenter since an M 5.1 on March 29, 2014 and prior tot that an M 4.5 on August 8, 2012. The only other such event in the area in the past 12 years was and M 4.7 on May 18, 2009. Forecast 127174 had expected today's event was likely within about 25 km today's epicenter around September 15.

 

O: 18SEP2020 15:42:47  34.0N  118.8W Ml=2.1  EMSC   CHANNEL ISLANDS REG., CALIFORNIA

O: 19SEP2020 06:45:03  34.1N  118.1W Ml=2.1  EMSC   GREATER LOS ANGELES AREA, CALIF.

O: 19SEP2020 06:38:45  34.0N  118.1W Mw=4.5  EMSC   GREATER LOS ANGELES AREA, CALI

P: 15SEP2020 127174    33.9N  118.3W 2.5-4.4 BAAAA  So. California             

 

O: 19SEP2020 04:22:49  34.4N  119.3W ML=2.0  EMSC   SOUTHERN CALIFORNIA

O: 19SEP2020 04:05:06  34.4N  119.3W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 19SEP2020 05:06:03  34.5N  119.3W Ml=2.1  EMSC   SOUTHERN CALIFORNIA          

P: 17SEP2020 127177    35.0N  119.2W 2.5-4.5 AAAAA  So. California             

 

TIDAL STRESSES HELP PROMOTE FIJI ISLANDS M 5.6

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 17, 2020

 

An M 5.4-5.6 also continued the current activation of seismicity in the Fiji/Tonga area. It was not reported felt in this area. This is the strongest earthquake within about 150 km of this epicenter since an M 6.4 on August 19, 2018. Forecast 127279 had expected today's event in this region was likely around September 19. As it occurred near the IDL, it was probably enhanced by high tidal stresses associated with today's new moon as described in previous issues of this summary:

 

"The new moon arrived September 17, 2020 at 11:00 UT. Longitudes which were at sub-solar locations (local solar noon) are near 15 East longitude and include western Europe while those anti-solar regions are near 165 West longitude including areas near the International Date Line (IDL) at 180 East longitude such as the Aleutian Islands, Kamchatka and areas of Tonga, Fiji and regions of the southwest Pacific. These areas will probably see enhanced seismicity in the next week. Other areas may also see tidally-promoted seismicity during this time when a set of strong earthquakes is likely especially in the southwestern and northern Pacific rim." (September 15-17, 2020)

 

O: 17SEP2020 17:01:33  16.7S  177.1W Mw=5.4  EMSC   FIJI REGION                  

O: 17SEP2020 17:01:32  16.6S  177.3W Mw=5.6  ANSS   FIJI REGION                  

P: 19SEP2020 127279    16.0S  176.0W 4.0-5.6 AAAAA  Tonga Islands              

 

The second strongest earthquake in the world today was an M 5.5 in the Banda Sea, Indonesia. NEIC reported it was felt with intensity II-III in Northern Territory, Australia at Palmerston and Darwin. This earthquake occurred within half an hour of the new moon and may also have been promoted by strong tidal stresses associated with that alignment. This is the strongest aftershock to date of the M 6.8 Banda Sea quake of May 6, 2020. Forecast 127089 had expected today's event within about 100 km was likely around September 14.

 

O: 17SEP2020 10:32:26   6.8S  129.3E Mw=5.5  EMSC   BANDA SEA                    

P: 14SEP2020 127089     6.0S  130.0E 4.0-5.6 BAAAA  West Irian, PNG            

 

The largest earthquakes in the U.S. or Canada today were an M 4.1 and 3.9 in the

region of the Alaska Peninsula. These are regional aftershocks of the M 7.8 of July 22 in the Alaska Peninsula. The M 3.9 south of the aftershock zone  was somewhat unusual. The last event within about 50-100 km of this epicenter with M>=3.9 was an M 4.2 on July 16, 2010. Forecast 127230 expected today's activity between September 16 and 18.

 

O: 17SEP2020 19:44:42  53.9N  158.1W mb=3.9  EMSC   SOUTH OF ALASKA              

P: 18SEP2020 127230    54.8N  157.7W 3.5-5.3 AAAAA  Alaska Peninsula           

 

O: 17SEP2020 07:51:39  54.8N  160.7W ml=4.1  EMSC   ALASKA PENINSULA             

P: 16SEP2020 127230    54.8N  159.7W 3.5-5.3 AAAAA  Alaska Peninsula           

 

The swarm in the Dominican Republic continued today with an event of M 4.2 and a number of aftershocks with M>=3. This swarm had been noted in the previous issue of this summary as:

 

 

"An earthquake of M 4.5 in the Dominican Republic today continued the activation of that region. NEIC reported it was felt with maximum intensity IV in Nagua Maria and II-III in the Dominican Republic at Las Terrenas, Cenove Duarte, Villa Altagracia, Moca, Santo Domingo, Santiago. This continues active conditions in the Dominican Republic but was to the  east of much of the recent activity. For example, an M 4.0 occurred about 200  km southwest of today's event on September 15 and recent swarms hit northwest of this over the past several days. The last earthquake of M>=4.5 in the Dominican Republic was an M 4.7 about 200 km east of today's event on May 6, 2020. The only other such event in the Dominican Republic in the past year was an M 4.9 on March 6, 2020 which occurred about 200 km southeast of today's epicenter. Forecast 127123 had expected today's activity was likely around September 17."  (September 17, 2020)

 

Forecast 127118 had expected today's activity within about 50 km was likely around September 17.

 

O: 18SEP2020 01:14:51  18.5N   71.0W ML=4.2  EMSC   DOMINICAN REPUBLIC

O: 17SEP2020 22:47:47  18.7N   70.8W ML=3.3  EMSC   DOMINICAN REPUBLIC

O: 17SEP2020 22:50:05  18.7N   70.8W ML=3.6  EMSC   DOMINICAN REPUBLIC

O: 18SEP2020 01:44:35  18.7N   70.8W ML=3.0  EMSC   DOMINICAN REPUBLIC

O: 18SEP2020 03:23:12  18.7N   68.8W ML=3.2  EMSC   DOMINICAN REPUBLIC

O: 17SEP2020 23:22:23  18.8N   70.8W ML=3.1  EMSC   DOMINICAN REPUBLIC

O: 17SEP2020 23:28:14  18.8N   70.8W ML=3.2  EMSC   DOMINICAN REPUBLIC

O: 17SEP2020 16:17:54  18.9N   70.4W ML=3.0  EMSC   DOMINICAN REPUBLIC

O: 17SEP2020 19:51:17  18.0N   70.7W ML=3.0  EMSC   DOMINICAN REPUBLIC REGION    

P: 17SEP2020 127118    19.0N   71.0W 3.4-4.9 AAAAA  Puerto Rico                

 

MODERATE QUAKES IN NORTH ATLANTIC; LOYALTY ISLANDS

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 16, 2020

 

A moderately strong M 5.7 aftershock occurred today in the central mid-Atlantic Ocean. It was not reported felt in this area. It follows an M 6.6 on September 6 and is probably an aftershock of that event. Tropical Storm Teddy (now a hurricane) formed over this epicenter on September 13-14 and probably helped trigger today's earthquake. This summary noted at the time:

 

"TS Teddy continued today in the mid-Atlantic with winds up to 50 kts. It is expected to track to the west over the next week. Some enhanced seismicity may occur in the northern Mid-Atlantic ridge area in the next several days …" (September 14, 2020)

 

When the M 6.6 mainshock in this area occurred on September 6, this summary noted:

 

"The strongest earthquake in the world today was an  M 6.6 in the Central Mid-Atlantic Ridge. It was not reported felt in this remote area. This is the strongest earthquake within about 250 km of this epicenter since an M 6.6 on September 10, 2008, the only such event in the area in the past 30 years. Forecast 126789 had expected a moderately large regional event in this area was likely around September 7. This epicenter is at 101 degrees from the M 7.8 in the Alaska Peninsula of July 22 and was probably promoted by energy from that source." (September 6, 2020)

 

Forecast 127053 had expected today's event within the central mid-Atlantic was likely within about 100 km of this epicenter around September 16. This epicenter is located at 101-102 degrees from the M 7.8 in the Alaska Peninsula of July 22, 2020 and was probably promoted by concentrated energy from that source. This event occurred near local solar midnight and was probably enhanced by energy from the new moon as noted in this and previous issues of this summary:

 

“The new moon will arrive September 17, 2020 at 11:00 UT. Longitudes which are at sub-solar locations (local solar noon) are near 15 East longitude and include western Europe while those anti-solar regions are near 165 West longitude including areas near the International Date Line (IDL) at 180 East longitude such as the Aleutian Islands, Kamchatka and areas of Tonga, Fiji and regions of the southwest Pacific. These areas will probably see enhanced seismicity in the next week. Other areas may also see tidally-promoted seismicity during this time when a set of strong earthquakes is likely especially in the southwestern and northern Pacific rim.” (September 15-17, 2020)

 

O: 17SEP2020 03:00:20   7.6N   37.0W Mw=5.7  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P: 16SEP2020 127053     8.0N   38.0W 4.0-5.6 AAAAA  Central Mid-Atlantic Ridg  

 

A moderately large M 5.6 also occurred today in the area southeast of the Loyalty Islands south of Vanuatu. It was not reported felt in this remote epicentral area. The last earthquake within about 200 km of this epicenter in the area southeast of the Loyalty Islands with M>=5.6 occurred on December 2, 2018 with M 5.7 two days before an M 7.5 about 250 km to the west of today's epicenter. Forecast 127285 had expected today's event within about 150 km was likely around September 19.  This epicenter is located at 101-102 degrees from the M 7.0 in the Atacama Chile event of September 1, 2020 and was probably promoted by concentrated energy from that source. A swarm in northern Canada today including an M 3.5 was also located at this distance from Atacama, Chile.

 

O: 16SEP2020 08:44:30  22.3S  171.6E Mw=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 19SEP2020 127285    23.0S  170.0E 4.0-5.4 BABAA  Loyalty Islands            

 

An earthquake of M 4.5 in the Dominican Republic today continued the activation of that region. NEIC reported it was felt with maximum intensity IV in Nagua Maria and II-III in the Dominican Republic at Las Terrenas, Cenove Duarte, Villa Altagracia, Moca, Santo Domingo, Santiago. This continues active conditions in the Dominican Republic but was to the east of much of the recent activity. For example, an M 4.0 occurred about 200 km southwest of today's event on September 15 and recent swarms hit northwest of this over the past several days. The last earthquake of M>=4.5 in the Dominican Republic was an M 4.7 about 200 km east of today's event on May 6, 2020. The only other such event in the Dominican Republic in the past year was an M 4.9 on March 6, 2020 whihc occurred about 200 km southeast of today's epicenter. Forecast 127123 had expected today's activity was likely around September 17.

 

O: 16SEP2020 12:06:26  19.3N   69.9W mb=4.5  EMSC   DOMINICAN REPUBLIC           

P: 17SEP2020 127123    20.0N   71.0W 3.0-4.6 AAAAA  Bahamas/No. Caribbean      

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the Rat Islands, Aleutians. It was not reported felt in this remote area. The last earthquake in the Rat Islands with M>=4.2 was an M 4.7 on August 27, 2020. Forecast 127245 had expected today's event was likely around September 17.

 

O: 17SEP2020 03:29:26  52.3N  177.8E mb=4.2  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 17SEP2020 127245    51.0N  177.0E 4.0-5.8 ABAAA  Rat Islands                

 

An unusual M 3.4 shook the border between eastern Utah and Colorado today. NEIC reported this earthquake of M 3.4 in Colorado  was felt with intensity II-III in the area(s) of Utah at Provo, and Lehi. The last earthquake of M>=3.4 within about 150 km of this epicenter in Colorado or Utah was an M 4.5 on March 4, 2019 and prior to that an M 3.9 on January 24, 2013. Forecast 127149 had expected today's event was likely within about 10 km around September 18.

 

O: 16SEP2020 15:26:40  38.3N  108.9W ML=3.4  EMSC   COLORADO                     

P: 18SEP2020 127149    38.3N  108.9W 2.0-4.4 AAAAA  Colorado area              

 

MODERATE EARTHQUAKE SHAKES NEPAL

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 15, 2020

 

An unusual earthquake of M 5.3 occurred today in Nepal. NEIC reported it was felt with intensity IV in Nebal at Bhimeshwar, Dhulikhet, Banepa, Panauti, Bhaktapur,Tribuvannagar, Kathmando, Lalitpur, Kirtipur and Kamalama, Nepal.

This was the largest earthquake located in the world today. This is the largest earthquake in Nepal located within about 200 km of this epicenter since an  M 5.4 on November 27, 2016. These are probably aftershocks of the great M 7.8 quake of April 25, 2015 which did much damage to built structures in the area and which occurred about 100 km northwest of today's epicenter. The event was followed by an M 7.3 about 25 km from today's epicenter on May 12, 2015. Forecast 127190 had expected moderate seismicity to the northwest of this was likely in mid-September.

 

O: 15SEP2020 23:34:03  27.9N   85.9E mb=5.3  EMSC   NEPAL                        

P: 17SEP2020 127190    30.0N   82.0E 3.8-5.3 ACCAA  Xizang                      

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in western Nevada. NEIC reported it was felt with intensity II in the epicentral area.

This is the strongest aftershock in western Nevada of the M 6.5 of May 15, 2020 since an M 4.2 shook the region on July 23, 2020 and was followed by an M 4.4 about 30 km to the east on July 26, 2020.  Forecast 127142 had expected today's event within about 25 km of this epicenter was likely around September 17.

 

O: 15SEP2020 16:52:41  38.2N  118.0W ml=2.4  EMSC   NEVADA

O: 15SEP2020 17:37:43  38.2N  118.0W ml=2.3  EMSC   NEVADA

O: 15SEP2020 17:59:55  38.2N  117.9W ml=2.4  EMSC   NEVADA

O: 15SEP2020 17:59:55  38.2N  117.9W ml=2.4  EMSC   NEVADA

O: 16SEP2020 03:49:26  38.2N  118.0W ml=2.7  EMSC   NEVADA

O: 16SEP2020 04:08:34  38.2N  118.0W ml=2.0  EMSC   NEVADA

O: 15SEP2020 16:33:35  38.2N  117.9W ML=4.0  EMSC   NEVADA                       

O: 15SEP2020 16:33:35  38.2N  117.9W ML=4.2  ANSS   NEVADA                       

P: 17SEP2020 127142    37.9N  118.2W 2.5-4.4 AAAAA  California/Nevada area     

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 14, 2020

 

The strongest earthquake in the world today was an M 6.4 in the region of Kamchatka. Today's event in Kamchatka was accompanied by smaller regional earthquakes. It occurred at the height of the strongest geomagnetic storm since September 1. The last earthquake of M>=5.5 in Kamchatka was an M 5.5 which occurred on September 1, 2020 at the height of the previous large geomagnetic storm and was noted in this summary at the time:

 

" M 5.6 in Kamchatka, Russia. These event are not uncommon but illustrate the impact that geomagnetic storms can have on antipodal seismicity. The Kamchatka event occurred within about 30 minutes of local solar noon while the South Sandwich event occurred near local solar midnight. Both may also have been affected by strong tidal stresses associated with the full moon which maximize at these hours." (September 1, 2020)

 

and

 

"Antipodal activity at moderate levels continued today in the South Sandwich Islands (M 4.7) and as a swarm in the region of Kamchatka. This antipodal activity began several days ago and may involve some volcanic activity in Kamchatka." (September 5, 2020)

 

Today's earthquake at high latitude in Kamchatka was located at a deep focus and was not reported felt in the epicentral area and occurred near local solar noon.

The last earthquake in Kamchatka of M>=6.4 occurred as an M 6.9 on June 10, 2004. The only other such event in this area in the past 30 years was an M 6.9 on June 16, 2003. Today's event is the strongest intermediate to deep focus earthquake in this area of Kamchatka in the past 30 years. Forecast 127238 had expected today's event was likely in this area around September 14.

 

O: 15SEP2020 03:41:25  56.0N  158.4E Mw=6.4  EMSC   KAMCHATKA PENINSULA, RUSSIA  

P: 14SEP2020 127238    56.0N  160.0E 4.0-5.4 AAAAA  E. of Kamchatka            

 

The event in Kamchatka was followed 30 minutes later by an M 6.1 in the area of Fiji west of Samoa. It was reported by NEIC to have been felt in Lombasa, Fiji with intensity V. The Fiji  event occurred at a distance of 72 degrees from Kamchatka (node 5). Surface waves from Kamchatka were in the epicentral area of the Fiji quake at the time it occurred and probably triggered it.

 

This activity may also have been promoted by geomagnetic effects. A geomagnetic storm reached maximum intensity at high latitudes at the time of the Kamchatka earthquake and probably promoted it. Fiji is on the geomagnetic equator. This summary noted this geomagnetic storm as:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 11.  High latitude geomagnetic field also saw active conditions with AP 25. This is the most active geomagnetic storm since the strong storm at the end of August and early September. Such storms can enhance seismicity near the geomagnetic equator and at high latitudes" (September 14, 2020)

 

The area to the east of this has recently seen moderate to large scale activity in Samoa. These included an M 5.2 on September 9 and an M 5.4 on September 8, 2020. These events were more than 500 km to the east of today's epicenter. The last event within about 250 km of today's Fiji quake with M>=6.1 and west of 180 degrees longitude was an M 6.2 twenty years ago today on September 14, 2000, the only such event in this area in the past 30 years. Earthquakes about 250 km to the southwest of this occurred on April 7, 2006 (M 6.4) and November 22, 2001 (M 6.2), but today's earthquake is a highly unusual regional event.  Forecast 127270 had expected today's event in this area was likely around September 18.

This earthquake is at 100 degrees from the M 7.0 Atacama, Chile event of September 1 and may have been promoted by concentrated energy from that source.

It is also at the fifth node (72 degrees) from the earlier Kamchatka M 6.4 and from the M 7.8 in the Alaska Peninsula of July 22 and may have also been promoted by energy from those sources.

 

O: 15SEP2020 04:12:17  15.0S  179.8E Mw=6.1  EMSC   FIJI                         

P: 18SEP2020 127270    16.0S  178.0E 4.0-5.6 BABAA  Fiji Islands               

 

The activity in Kamchatka and Fiji today may also have been promoted by tidal stresses associated with the upcoming new moon of September 17 as described in this summary as:

 

"The new moon will arrive September 17, 2020 at 11:00 UT. Longitudes which are at sub-solar locations (local solar noon) are near 15 East longitude and include western Europe while those anti-solar regions are near 165 West longitude including areas near the International Date Line (IDL) at 180 East longitude such as the Aleutian Islands, Kamchatka and areas of Tonga, Fiji and regions of the southwest Pacific. These areas will probably see enhanced seismicity in the next week. Other areas may also see tidally-promoted seismicity during this time when a set of strong earthquakes is likely especially in the southwestern and northern Pacific rim." (September 14, 2020)

 

The strongest earthquakes in the U.S. or Canada today were a pair of M 3.4 events in Northern California. NEIC reported these earthquakes of M 3.4 in Northern California were felt with intensity II-III in the area(s) of Northern California at Laytonville, Percy, Covelo and Leggett. This activity is the largest within about 50 km of these epicenters since an M 4.3 on December 14, 2017. Forecast 127145 had expected these events in this area were likely around September 16.

 

O: 14SEP2020 14:15:16  39.9N  123.4W ML=3.0  EMSC   NORTHERN CALIFORNIA          

O: 14SEP2020 14:15:16  39.9N  123.4W ML=3.4  ANSS   NORTHERN CALIFORNIA          

O: 14SEP2020 15:36:58  39.9N  123.3W ML=2.9  EMSC   NORTHERN CALIFORNIA

O: 14SEP2020 15:36:58  39.9N  123.3W ML=3.4  ANSS   NORTHERN CALIFORNIA

P: 16SEP2020 127145    39.3N  123.2W 2.5-4.8 AAAAA  Central California         

 

 

L

 

UNUSUAL M 5.0 IN SAKHALIN, RUSSIA

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 13, 2020

 

An unusual series of moderate earthquakes occurred today in the region of Sakhalin, Russia. This included an M 4.9-5.0 and several aftershocks of M 4.6 and 3.9. These were not reported felt in the epicentral area. It may have been promoted by stresses associated with Super Typhoon Haishen which passed over the area on September 8 as noted in this summary at the time:

 

"Super-Typhoon Haishen (TD 11W) continued today over Korea with winds up to 45 kts. It is expected to dissipate in the next day." (September 8, 2020)

 

The only moderate earthquake located in Sakhalin, Russia in the past year was an

M 4.2 on January 23, 2020. But the last shallow focus event in Sakhalin within about 200 km of today's event with M>=4.9 was an M 5.2 on April 23, 2017. An earthquake of M 5.6 also occurred at deep focus on July 1, 2018. Strong earthquakes and tsunamis can occur in the area but are uncommon. The last major event in the region of Sakhalin was an M 6.8 on August 8, 2000 and generated a major damaging and deadly tsunami. Forecast 127222 had expected today's event was likely in this area around September 15. This activity is located at 147 degrees from the M 7.0 in Atacama, Chile of September 1 and may have been promoted by energy from that source.

 

O: 13SEP2020 13:42:26  48.9N  142.1E mb=5.0  ANSS   SAKHALIN, RUSSIA

O: 13SEP2020 13:42:26  49.0N  142.1E mb=4.9  EMSC   SAKHALIN, RUSSIA

O: 13SEP2020 16:12:43  49.0N  142.1E mb=3.9  EMSC   SAKHALIN, RUSSIA

O: 13SEP2020 14:09:01  48.9N  142.2E mb=4.6  EMSC   SAKHALIN, RUSSIA             

P: 15SEP2020 127222    47.0N  142.0E 3.5-5.7 ABAAA  So. Kurils                 

 

The strongest earthquake in the world today was an M 5.5 in eastern New Guinea.

NEIC reported this earthquake of M 5.5 in Papua New Guinea  was felt with intensity II-III in the area(s) of Papua New Guinea at Kainantu, Bulolo and Goroka. The last earthquake within about 200 km of this epicenter with M>=5.5 was an M  7.0 about 200 km southeast of today's epicenter on July 17, 2020. The last such event within the 200 km radius was an M 72. on May 6, 2019. Forecast 127076 had expected an event up to M 5.6 was likely in this area  around September 13.

 

O: 13SEP2020 10:28:19   6.0S  147.0E mb=5.5  EMSC   EASTERN NEW GUINEA REG., P.N.G

P: 13SEP2020 127076     5.0S  148.0E 4.0-5.6 AAAAA  New Ireland                

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in Southern Alaska. NEIC reported this earthquake of M 4.1 in southern Alaska  was felt with intensity II-III in the area(s) of southern Alaska at Valdez, Glennallen, Palmer, Copper Center, Chugiak, Girdwood, Eagle River, Wasilla, and Anchorage.

The last earthquake of M>=4.1 within about 150 km of this epicenter in southern Alaska occurred as an M 4.3 nearly two years ago on October 16, 2018. Forecast 127252 had expected today's event within about 50 km of this epicenter was likely around September 16. This event is located at 104 degrees from the M 7.0 in Sumatra of August 18 and 107 degrees from the Atacama quake of September 1, 2020 and was probably promoted by concentrated seismic energy from those sources.

 

O: 13SEP2020 15:10:09  61.5N  146.4W ML=4.1  EMSC   SOUTHERN ALASKA              

P: 16SEP2020 127252    61.3N  147.2W 3.2-4.9 BAAAA  Central Alaska             

 

 

The northern Caribbean continued at active seismic conditions today. The strongest earthquake in the area was an M 4.4 in the U.S. Virgin Islands. This was joined by a continuing swarm in the Dominican Republic and aftershocks in Haiti and southern Puerto Rico.  A similar earthquake of M 4.4-4.5 occurred in the Virgin Islands on August 26, 2020. The only other earthquake of M>=4.4 in the Virgin Islands in the past year was an M 5.0 on October 6, 2019. Forecast 127105 had expected today's event in the Virgin Islands within about 50 km of the epicenter of the M 4.4 This activity may have been enhanced by the passage of several tropical storms and hurricanes to the north as detailed in previous issues of this summary:

 

"TS Paulette continued today over the northern Mid-Atlantic ridge with winds up to 55 kts. It is expected to track to the west over the several days. Some seismic enhancement is possible at this time in the central mid-Atlantic Ridge as Paulette passes over. It will pass near Bermuda as a hurricane, but this area has little seismicity." (September 11, 2020)

 

NEIC reported this earthquake of M 4.4 in the Virgin Islands  was felt with intensity II-III in the area(s) of the Virgin Islands at San Juan, Puerto Rico.

 

O: 13SEP2020 07:12:57  19.2N   64.5W mb=4.4  EMSC   VIRGIN ISLANDS REGION        

P: 13SEP2020 127105    19.0N   64.0W 3.0-5.1 AAAAA  Leeward Islands            

 

VANUATU ISLANDS CONTINUES ACTIVE

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 12, 2020

 

The largest earthquake in the world today was an M 5.9-6.0 in central Vanuatu. NEIC reported it was felt with intensity II in Vila Shefa, Vanuatu. An earthquake of M 6.2 hit the area on September  7 following a similar event on September 6. Today's event is probably an aftershock of that. At the time this summary noted in this regard:

 

 

"The M 6.2 in Vanuatu was reported by NEIC to have been felt with intensity IV in Vila Shefa, Vanuatu. It was accompanied by aftershocks of M 4.9, 5.1 and 5.2. It occurred in an area of active volcanism and may have been related to that. The last shallow focus earthquake within about 250 km of this epicenter in the Vanuatu Islands with M>=6.2 was an M 6.5 on August 21, 2018 and prior to that an M 7.0 on April 28, 2016. Forecast 127011 had expected today's event within about 25 km was likely around September 7. This epicenter is at 103-105 degrees from the earthquake of M 7.0 in Atacama, Chile of September 1 and from the M 6.3 in Coquimbo, Chile today  and from the M 7.4 in Oaxaca, Mexico of June 23 and was probably promoted by energy from those sources." (September 5-6, 2020)

 

Forecast 127280 had expected this activity was likely around September 15.

Note that the earthquake of M 6.1 in Honshu, Japan, like this event in Vanuatu, was also located at 103 degrees from Oaxaca, Mexico.

 

O: 12SEP2020 08:34:27  17.1S  167.6E Mw=5.9  EMSC   VANUATU                      

P: 15SEP2020 127280    18.0S  168.0E 4.0-5.4 BAAAA  Vanuatu Islands            

 

 

The northern Caribbean was at active seismic conditions today. The strongest earthquake in the area was an M 4.4 in the U.S. Virgin Islands.  A similar earthquake of M 4.4-4.5 occurred in the Virgin Islands on August 26, 2020. The only other earthquake of M>=4.4 in the Virgin Islands in the past year was an M 5.0 on October 6, 2019. Forecast 127105 had expected today's event in the Virgin Islands within about 50 km of the epicenter of the M 4.4 This activity may have been enhanced by the passage of several tropical storms and hurricanes to the north as detailed in previous issues of this summary:

 

"TS Paulette continued today over the northern Mid-Atlantic ridge with winds up to 55 kts. It is expected to track to the west over the several days. Some seismic enhancement is possible at this time in the central mid-Atlantic Ridge as Paulette passes over. It will pass near Bermuda as a hurricane, but this area has little seismicity." (September 11, 2020)

 

NEIC reported this earthquake of M 4.4 in the Virgin Islands  was felt with intensity II-III in the area(s) of the Virgin Islands at San Juan, Puerto Rico.

 

O: 12SEP2020 23:22:04  19.1N   64.4W mb=4.4  EMSC   VIRGIN ISLANDS REGION

O: 12SEP2020 08:10:26  19.2N   64.8W ML=3.0  EMSC   VIRGIN ISLANDS REGION

O: 12SEP2020 08:03:46  19.0N   64.9W ML=3.3  EMSC   VIRGIN ISLANDS REGION        

P: 13SEP2020 127105    19.0N   64.0W 3.0-5.1 AAAAA  Leeward Islands            

 

Enhanced seismicity also occurred today in the region of Haiti with events of M 3.4 and 3.5 and as a series of light earthquakes of M 3.0-3.5 in the Dominican Republic, continuing active seismicity in that region. An M 3.7 occurred on September 11 in Haiti but only one earthquake of M>=4 has occurred in this region in the past year - an M 4.7 on May 31, 2020.

 

O: 13SEP2020 00:50:37  19.5N   73.9W ML=3.4  EMSC   HAITI REGION

O: 13SEP2020 00:49:17  19.5N   73.9W ML=3.5  EMSC   HAITI REGION                 

P: 17SEP2020 127118    19.0N   71.0W 3.4-4.9 BACAA  Puerto Rico                

 

The activity in the Dominican Republic follows a similar swarm in the area that occurred yesterday, September 11. Two earthquakes of M 3.6 were recorded today, the largest in the area since an M 4.4 on August 25. Forecast 127123 had expected today's activity in the Dominican Republic was likely in mid-September.

 

O: 12SEP2020 07:10:11  18.7N   69.3W ML=3.5  EMSC   DOMINICAN REPUBLIC

O: 12SEP2020 07:14:14  19.2N   70.8W ML=3.2  EMSC   DOMINICAN REPUBLIC

O: 12SEP2020 07:32:30  19.2N   68.6W ML=3.2  EMSC   DOMINICAN REPUBLIC REGION

O: 12SEP2020 11:23:39  19.6N   69.9W ML=3.4  EMSC   DOMINICAN REPUBLIC

O: 12SEP2020 18:49:17  19.8N   70.7W ML=3.2  EMSC   DOMINICAN REPUBLIC

O: 12SEP2020 08:23:21  20.1N   70.8W ML=3.6  EMSC   DOMINICAN REPUBLIC REGION

O: 12SEP2020 08:38:23  20.1N   70.8W ML=3.4  EMSC   DOMINICAN REPUBLIC REGION

O: 12SEP2020 10:02:24  20.2N   70.7W ML=3.5  EMSC   DOMINICAN REPUBLIC REGION

O: 12SEP2020 11:39:12  20.2N   70.7W ML=3.4  EMSC   DOMINICAN REPUBLIC REGION

O: 12SEP2020 15:18:42  20.5N   70.4W ML=3.3  EMSC   DOMINICAN REPUBLIC REGION    

P: 17SEP2020 127123    20.0N   71.0W 3.0-4.6 BAAAA  Bahamas/No. Caribbean      

 

TYPHOONS PROMOTE STRONG EARTHQUAKE OFF NORTHERN HONSHU, JAPAN

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 11, 2020

 

The strongest earthquake of the day was an M 6.1 off the east coast of northern Honshu, Japan. NEIC reported it was felt with intensity IV in Japan at Miyagi and Fukushima and II-III in Aomori, Chiba, Tokyo, and Shizuoka. JMA reported intensity III-IV in Aomori, Iwate and Miyagi, Akita, Yamagata, Fukushima, Ibaraki. This event may have been enhanced by energy from Super-Typhoon Haishen and a storm currently located south of Honshu, Japan as reported in the previous issue of this summary:

 

"A tropical cyclone may be forming south of Honshu, Japan. It is currently located at 25N 141E in the Volcano Islands of Japan and expected to track to the north over the next several days. Some seismic enhancement may occur in the Volcano and Bonin Islands with this storm and later in eastern Honshu, Japan." (September 10, 2020)

 

and

 

"TD 12W continued today off Honshu, Japan with winds up to 35 kts. It is expected to track to the northeast and to enhance seismicity off the coast of Honshu, Japan in the next several days." (September 11, 2020)

 

and

 

"Super-Typhoon Haishen (TD 11W) continued today north of the Ryukyu Islands, Japan with winds up to 115 kts. It is expected to track to the north reaching southern Honshu and Kyushu September 6-7. It could promote a moderate to strong earthquake in western Honshu or the Ryukyu Islands with or after landfall." (September 7, 2020)

 

Today's event of M 6.1 off the coast of Honshu, Japan was the strongest within  about 150 km of this epicenter since can M 6.3 on April 19, 2020. The only other such  earthquake in the past three years in this region was an M 6.3 on August 4, 2019. Forecasts 127164, 127181 and 126895 had expected today's activity between September 7 and 18. This epicenter is also at 147 degrees from the M 6.3 in Tarapaca, Chile earlier in the day. This is a distance at which energy is concentrated on the surface after internal earth reflections and often sees elevated seismicity after major earthquakes. Likewise it is at 103 degrees from the M 7.5 in Oaxaca, Mexico of June 23, 2020, a distance where similar concentration of energy occurs following major earthquakes. The activity in Honshu had been expected in this summary at that time as:

 

"Far-field triggering is likely with this earthquake. ...  Areas at 103 degrees from the Oaxaca epicenter include the east coast of Honshu, Japan" (June 24, 2020)

 

Recent strong activity, including an M 5.1 today, in Vanuatu is also occurring at 103 degrees from Oaxaca.

 

O: 12SEP2020 02:50:42  38.7N  142.1E mb=4.9  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 12SEP2020 03:00:30  38.7N  142.3E ML=4.2  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 12SEP2020 03:03:30  38.7N  142.2E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 12SEP2020 03:49:05  38.7N  142.3E Mw=4.5  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 12SEP2020 02:44:12  38.8N  142.1E Mw=6.1  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 18SEP2020 127164    38.0N  141.0E 4.0-5.5 CAAAA  Off East Coast Honshu      

P: 18SEP2020 127181    38.0N  143.0E 4.0-5.4 CAAAA  So. of Honshu              

P:  7SEP2020 126895    39.0N  142.0E 4.0-5.5 BAAAA  Off East Coast Honshu      

 

The strongest earthquake in the U.S. or Canada today was an M 4.3-4.6 in Southern Alaska. NEIC reported it was felt with intensity II-III in Southern Alaska at Willow, Anchorage, Wasilla, Kenai.  NEIC reported an aftershocks of M 3.4 in  southern Alaska was felt with intensity II-III in the area(s) of southern Alaska at Elmendorf AFB, Anchorage, Fort Richardson, Wasilla.  The last earthquake within about 150 km of this epicenter with M>=4.6  occurred October 4, 2019 and prior to that on September 17, 2019. Forecast 127255 had expected today's event was likely within about 50 km around September 14.

 

O: 11SEP2020 13:58:31  61.6N  152.2W mb=4.6  EMSC   SOUTHERN ALASKA              

P: 14SEP2020 127255    61.3N  152.3W 3.2-5.1 BAAAA  Central Alaska             

 

An M 4.0-4.2 was also felt widely in the aftershock zone in Central California near the Nevada border. It was followed by several aftershocks of M 3.3 and 3.6. NEIC reported the M 4.2 was felt with intensity II-III in California at Three Rivers, Lone Pine, Kings Canyon National Park, Ridgecrest, Visalia, Delano, Sanger and Fresno. It is likely this activity was triggered by seismic waves from the M 6.2 in Tarapaca, Chile which occurred 20 minutes earlier at 72 degrees distance. The S-phase from Chile arrived in central California at the same time the activity in Central California began and is the likely trigger for this activity. Today's event is an aftershock of the M 5.8 of June 24 and M 4.6 of June 23, 2020 and is the largest such aftershock since June 24. An M 4.8 occurred about 50 km to the east of today's epicenter on August 19, 2020. Forecast 127140 had expected today's event was likely around September 15.

 

O: 11SEP2020 08:11:04  36.4N  118.0W ML=3.1  EMSC   CENTRAL CALIFORNIA

O: 11SEP2020 08:12:22  36.4N  118.0W Ml=2.0  EMSC   CENTRAL CALIFORNIA

O: 12SEP2020 04:44:50  36.4N  118.0W Ml=2.3  EMSC   CENTRAL CALIFORNIA

O: 11SEP2020 08:14:09  36.5N  118.0W ML=3.4  EMSC   CENTRAL CALIFORNIA

O: 11SEP2020 07:55:44  36.4N  118.0W ML=4.0  EMSC   CENTRAL CALIFORNIA           

O: 11SEP2020 07:55:44  36.4N  118.0W ML=4.2  ANSS   CENTRAL CALIFORNIA           

P: 15SEP2020 127140    36.1N  118.1W 2.5-4.4 BAAAA  California/Nevada area     

 

Moderate earthquakes in the Tarapaca area of northern Chile continued to be felt in the Iquique, Tarapaca area today. This summary noted this activity in the previous issue as:

 

 

"A strong M 6.3 hit the northern Chile region of Tarapaca today. Minor damage was felt in the epicentral region near Tocopilla, Antofagasta, Chile (VII) with NEIC reporting VI in Iquique, Tarapaca and V in Calama and Arica, Antofagasta.

GUC reported this earthquake was felt with intensity  VI in  Tarapaca at Iquique and in Arica at Arica with IV, Chile. This is part of a series of strong earthquakes along the coast of Chile in the past week which has included an M 6.9 in Atacama and an M 6.2 in Coquimbo, Chile to the south of today's epicenter. The last earthquake within about 200 km of today's epicenter with M>=6.3 occurred as an M 8.2 and aftershocks in early April, 2014 about 150-200 km to the north of today's epicenters. Forecast 127016 had expected today's event within about 100 km was likely around September 9. This epicenter is near 106 degrees from the M 7.8 in the Alaska Peninsula of July 22. Seismic energy from large events can concentrate at this distance and help trigger larger regional events." (September 11, 2020)

 

O: 11SEP2020 07:35:56  21.4S   69.8W Mw=6.3  EMSC   TARAPACA, CHILE

O: 11SEP2020 10:13:43  21.4S   70.0W mb=4.5  EMSC   TARAPACA, CHILE

O: 12SEP2020 06:45:04  21.4S   69.9W mb=4.5  EMSC   TARAPACA, CHILE

O: 11SEP2020 08:25:07  21.5S   69.9W mb=4.6  EMSC   ANTOFAGASTA, CHILE

O: 11SEP2020 09:48:07  21.3S   69.9W ML=4.0  EMSC   TARAPACA, CHILE              

P:  9SEP2020 127016    22.0S   69.0W 4.0-5.6 AAAAA  Coast No. Chile            

 

STRONG EARTHQUAKE SHAKES TARAPACA, CHILE

 

EARTHQUAKE SUMMARY FOR SEPTEMBER 10, 2020

 

A strong M 6.3 hit the northern Chile region of Tarapaca today. Minor damage was felt in the epicentral region near Tocopilla, Antofagasta, Chile (VII) with NEIC reporting VI in Iquique, Tarapaca and V in Calama and Arica, Antofagasta. GUC reported this earthquake was felt with intensity  VI in  Tarapaca at Iquique and in Arica at Arica with IV, Chile. This is part of a series of strong earthquakes along the coast of Chile in the past week which has included an M 6.9 in Atacama and an M 6.2 in Coquimbo, Chile to the south of today's epicenter. The last earthquake within about 200 km  of today's epicenter with M>=6.3 occurred as an M 8.2 and aftershocks in early April, 2014 about 150-200 km to the north of today's epicenters. Forecast 127016 had expected today's event within about 100 km was likely around September 9. This epicenter is near 106 degrees from the M 7.8 in the Alaska Peninsula of July 22. Seismic energy from large events can concentrate at this distance and help trigger larger regional events. This summary has noted the relation between southern Peru and northern Chile and the Alaska Peninsula in many previous issues such as when an M 5.5 hit Tarapaca on August 3:

 

"Other recent activity in southern Peru and northern Chile commented on in this summary may have been precursory to today's event. This event is at 104-105 degrees from the M 7.8 of July 22 n the Alaska Peninsula and was probably promoted by energy from that source." (August 4, 2020)

 

O: 11SEP2020 00:57:20  20.9S   69.1W mb=4.6  EMSC   TARAPACA, CHILE              

O: 11SEP2020 07:35:56  21.4S   69.8W Mw=6.3  EMSC   TARAPACA, CHILE              

O: 11SEP2020 07:35     21.4S   69.9W mb=6.3  GUC    Tarapaca at Iquique and in Ari

P:  9SEP2020 127016    22.0S   69.0W 4.0-5.6 AAAAA  Coast No. Chile            

 

A series of light earthquakes occurred in the Yellowstone National Park area of Wyoming today. These were reported with intensity II-III in the epicentral area of Yellowstone. The largest of these was an M 2.8. A less energetic swarm hit the Yellowstone region about 50 km to the northwest of today's epicenters on May 29 but the last event in the area with M>=2.8 occurred on March 31, 2020 with M 2.9 and followed the M 6.5 in southern Idaho. One of the strongest aftershocks of that event occurred with M 4.4 yesterday. The only earthquake of M>2.9 in Yellowstone in the past year was an M 3.2 on December 15, 2019. Forecast 126958 had expected today's activity in Yellowstone was likely around September 7. This activity is at the third node (120 degrees) from the Banda Sea and may have been promoted by energy from that source.

 

O: 10SEP2020 11:03:02  44.3N  110.5W Ml=2.1  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 11:40:22  44.3N  110.5W Ml=2.6  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 11:42:54  44.3N  110.5W ML=2.5  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 11:44:41  44.3N  110.5W Ml=2.1  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 11:48:47  44.3N  110.5W Ml=2.2  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 12:09:31  44.3N  110.5W Md=2.8  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 12:19:33  44.3N  110.5W Ml=2.4  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 12:21:58  44.3N  110.5W ML=2.5  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 12:23:14  44.3N  110.5W MD=2.2  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 12:50:06  44.3N  110.5W Ml=2.7  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 13:01:51  44.3N  110.5W Ml=2.3  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 13:07:01  44.3N  110.5W Ml=2.4  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 13:19:34  44.3N  110.5W Ml=2.2  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 13:26:40  44.3N  110.5W ML=2.5  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 13:40:46  44.3N  110.5W Ml=2.0  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 18:33:53  44.3N  110.5W ML=2.4  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 18:36:46  44.3N  110.5W ML=2.3  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 18:56:01  44.3N  110.5W Ml=2.0  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 19:57:39  44.3N  110.5W Ml=2.0  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O: 10SEP2020 10:54:34  44.3N  110.5W ML=2.0  EMSC   YELLOWSTONE NAT. PARK, WYOMING

P:  7SEP2020 126958    44.6N  110.8W 2.0-4.1 BAAAA  Yellowstone/Wyoming        

 

The largest earthquake in the U.S. or Canada today occurred south of the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote area. It may be an outer-rise earthquake indicating pent-up stress to the north near 174 East longitude in the Rat Islands. The last earthquake of M>=4.7 south of the Rat Islands within about 150 km of today's event was an M 4.9 on February 8, 2012. Forecast 126971 had expected today's earthquake in the Rat Islands was likely around September 10. It was also unusual today that no other earthquakes of M>=3 occurred in the area of Alaska east of the IDL. Seismicity in California was also at very low levels today with only four events of M>=2 and none of M>=2.3. It appears the aftershock sequences in that State may have been temporarily suspended.

 

O: 11SEP2020 04:44:33  50.6N  174.0E mb=4.7  EMSC   SOUTH OF ALEUTIAN ISLANDS     

P: 10SEP2020 126971    52.0N  176.0E 4.0-5.7 ABBAA  Rat Islands                

 

MODERATE QUAKES CONTINUE IN SOUTHWEST PACIFIC

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  9, 2020

 

Global seismicity returned to relatively quiet levels today after a week of active seismicity. The largest of today's events was an M 5.6 in the Talaud

Islands of Indonesia and was followed by a series of moderate aftershocks.

The second strongest was an  5.4 in the New Britain area, PNG. An M 5.2 also occurred near Samoa. These may be belatedly related to the strong geomagnetic storm at the beginning of September as they occurred near the geomagnetic equator. The event in Samoa is not an aftershock of the M 5.6 there yesterday as it occurred about 400 km to the west of that epicenter. It is the strongest within about 150 km of this epicenter since an M 5.7 on December 6, 2019. Forecast 127001 had expected this event within about 10 km of this epicenter was likely around September 7. The earthquakes in Samoa and New Britain are both at the fifth node (72 degrees) from the M 7.8 in Alaska of July 22 and were probably promoted by energy from that source.

 

O:  9SEP2020 22:55:55  14.9S  176.0W Mw=5.2  EMSC   SAMOA ISLANDS REGION         

P:  7SEP2020 127001    15.0S  176.0W 4.0-5.4 AAAAA  Samoa Islands              

 

The second largest earthquake in the world today was an M 5.4 in the Bougainville region, PNG near New Britain and the Solomon Islands. It continues an active period in the area which in recent days has included earthquakes of M 6.1 in New Britain on August 25; an M 6.0 in New Guinea on August 1 and an M 7.0 in New Guinea on July 17, 2020. The last event within about 200 km of today's epicenter with M>=5.4 was an M 5.4 on July 11, 2020 and prior to that an M 6.1 on May 7, 2020. Forecast 126809 had expected today's event to the north around September 9.

 

O:  9SEP2020 10:57:10   6.2S  154.4E Mw=5.4  EMSC   BOUGAINVILLE REGION, P.N.G.  

P:  9SEP2020 126809     4.0S  154.0E 4.0-5.7 ACAAA  New Britain                

 

The strongest earthquake today was an M 5.6 in the Talaud Islands, Indonesia.

It was followed by a number of moderate sized aftershocks. This is about 200 km east of the M 6.3 in the Mindanao, Philippines quake two days ago and was preceded by events to the south of M 5.9 on September 6 and to the east of M 6.4 on June 4, 2020. The last within about 150 km of today's epicenter with M>=5.6 occurred one year ago on September 10, 2019 with M 5.6. Forecast 126797 had expected today's activity was likely around September 8 within about 100 km of today's epicenter. This activity is near 144 degrees from the Atacama Chile quake of M 7.0 on September 1 and may have been promoted by energy from that source.

 

O: 09SEP2020 18:46:54   3.7N  127.2E ML=4.3  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 09SEP2020 07:41:19   4.0N  126.6E ML=4.4  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 09SEP2020 07:48:31   4.1N  126.8E ML=4.5  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 09SEP2020 07:18:43   4.2N  126.7E Mw=5.6  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 09SEP2020 08:51:51   4.2N  126.8E mb=4.5  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 09SEP2020 10:26:07   4.2N  126.9E ML=4.4  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 09SEP2020 08:04:01   4.5N  126.7E ML=4.6  EMSC   KEPULAUAN TALAUD, INDONESIA

O:  9SEP2020 14:17:16   3.7N  126.1E ML=4.2  EMSC   KEPULAUAN TALAUD, INDONESIA  

P:  8SEP2020 126797     4.0N  126.0E 4.0-5.4 AAAAA  Mindanao, Philippines      

 

The strongest earthquake in the U.S. or Canada today was an M 4.3 in Southern Alaska. NEIC reported this earthquake of M 4.0-4.3 in Southern Alaska  was felt with intensity II-III in the area(s) of Southern Alaska in Wasilla, Elmendorf, Willow, Anchorage, and Chugiak. The last earthquake with M>=4.3 within about 100 km of this epicenter was an M 5.2 nearly a year ago on September 17, 2019 and prior to that an M 4.4 on February 18, 2019. Forecast 126979 had expected today's event was likely around September 10.

 

O: 10SEP2020 02:17:59  61.5N  149.9W mb=4.3  EMSC   SOUTHERN ALASKA              

P: 10SEP2020 126979    61.0N  151.4W 3.2-4.9 AAAAA  Central Alaska             

 

Two light earthquakes of M 3.5-3.6 struck Hawaii today - in the area of the island of Hawaii and in Maui. This continues regional seismic enhancement which has been occurring in Hawaii in the past several days and has included an M 3.6-3.8 in Maui on September 5 and an M 4.3 in the island of Hawaii on September 6. Forecast 126857 had expected the Maui quake and 126833 the event south of the island of Hawaii in early September.

 

NEIC reported this earthquake of M 3.0 in Hawaii  was felt with intensity II-III in the area(s) of Hawaii at Naalehu, Captain Cook and Kamuela. The earthquakes in Hawaii and in Southern Alaska today are both at 103-104 degrees from the M 7.0 in Sumatra of August 18 and were probably promoted by  concentrated seismic energy from those sources.

 

O:  9SEP2020 10:18:41  19.2N  155.4W ML=3.5  EMSC   ISLAND OF HAWAII, HAWAII     

P:  9SEP2020 126833    18.8N  155.2W 3.0-4.4 AAAAA  Hawaii                     

 

O: 10SEP2020 03:47:13  20.3N  155.6W ML=3.6  EMSC   HAWAII REGION, HAWAII        

P:  5SEP2020 126857    20.1N  156.1W 4.0-5.5 BAAAA  Hawaii area                

 

IGHT, UNUSUAL QUAKES WIDELY FELT IN ENGLAND AND NEW JERSEY

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  8, 2020

 

An unusual earthquake of M 3.9 south of London, England today was widely felt. It was reported with intensity IV in England at Cheddington and Eaton Bray and II-III in Aston, Clinton, Ivinghoe-Pitstone, Tring, Wendover, Weston, Aylesbury, Chesham and Dunstable and as far to the north as Salford (V), Christchurch and London and Leven, in the west in Ireland and to the south in France. This is the strongest earthquake in southeastern England within about 200 of this epicenter since an M 3.9 on October 26, 2008 and an M 5.0 on April 28, 2007. However no earthquakes have occurred within 100 km of today's epicenter in the past 30 years. The closest was an M 4.4 on February 15, 1994.  Forecast 126975 had expected today's earthquake was likely in this area around September 9.

This epicenter is at 101 degrees from the M 7.0 in Atacama, Chile of September 1, 2020 and the M 7.0 in Sumatra of August 18, 2020. Seismic energy from large earthquakes returns to the surface at this distance from the mainshock after reflections and refractions off internal earth boundaries and can help trigger seismicity at this distance.

 

O:  8SEP2020 08:45:27  51.9N    0.7W ML=3.9  EMSC   ENGLAND, UNITED KINGDOM      

P:  9SEP2020 126975    51.0N    3.0W 3.0-4.5 AABAA  United Kingdom             

 

An M 3.1 earthquake was widely felt in New Jersey today. NEIC reported maximum intensity IV in New Jersey at Freehold, Marlbobo, Colts Neck, Englishtown, Farmingdale, Morganville, Howell, Lincroft, Eatontown and Holmdel among other communities. It was also reported felt lightly as far as New York, Maryland, Washington, D.C., Massachusetts, Virginia, New Hampshire, Pennyslvania, Ohio.

Earthquakes in New Jersey are not common but there are faults in the area such as the Rampino Fault on which these can occur. Another possibility for quakes in this area, which often are not well explained, include destabilizing clathrate deposits on the seabed offshore. The last earthquake in the region of New Jersey within about 150 km of this epicenter with M>=3.1 was an M 4.1 about 150 km to the southwest on November 30, 2017. The only earthquakes within this distance from today's epicenter in the past 30 years with M>=3.1 occurred August 5, 2003 (M 3.8) and January 9, 2992 (M 3.1). The strongest earthquakes in the area within about 200 km of today's event occurred on January 16, 1994 with M 4.2 and 4.6. These occurred hours before the Northridge earthquake in California and were probably precursory to that earthquake. Forecast 126939 had expected today's event to the northeast was likely in New England in early September. When the event occurred on November 30, 2017 this summary noted in this regard:

 

"The earthquake in Delaware is one of the strongest recorded in that State.

Earthquake in this area are often followed within days by a strong quake in  southern or central California, such as occurred in the Northridge quake of M 6.7 on January 17, 1994 (preceded by an M 4.6 in southern Pennsylvania on January 16, 1994) and the Morgan Hill quake of April 24, 1984 preceded by an M 4.4 in Pennsylvania on April 23, 1984.  The events in August 2011 were later found to occur at the time of one of the strongest cosmic ray events known, possibly associated with a gravity wave and other effects which may have triggered this series. A similar relation may be found with today's events, but these area usually not announced until extensive data anaylsis. As this list includes the largest events in the Delaware area in the past 50 years and some of the strongest earthquakes in Central and southern California in the same period, it may be significant. This correlation is strongest with moderate starting quakes in the region of Delaware. The area of southern California near Northridge is currently at the 23-year cycles of large quakes in the area. A moderate earthquake in the region west of Los Angeles and north to San Francisco is considered possible in the next four days. At the least, residents should check their earthquake preparedness kits to see if they are ready for a moderate quake at this time." (December 1, 2017)

 

Today's event in New Jersey was located at 144 degrees from the M 7.0 in Sumatra of August 18, 2020 and from the Banda Sea quake of August 21 (M 6.8). Other activity at this distance from Sumatra today included a series of moderate quakes in the Gulf of California and aftershocks in Coquimbo and Atacama, Chile.

 

O:  9SEP2020 06:00:13  40.3N   74.3W mb=3.1  EMSC   NEW JERSEY                   

P:  5SEP2020 126939    43.0N   71.0W 2.0-4.1 BCBAA  New England                

 

The strongest earthquake in the world today was an M 5.4 in the region of Samoa. NEIC reported it was felt with intensity III in the Apia Urban area of Samoa. This is not unusual seismicity for the area. An event of M 5.5 hit this same epicenter on May 5, 2020 and an M 6.0 was located in the area on March 17, 2020. Today's event is probably the strongest aftershock to date of the May 5 event. Forecast 127007 had expected today's activity around September 5. This epicenter is located at the fifth node (72 degrees) from the Alaska Peninsula M 7.8 of July 22. It was probably promoted from that source. Other earthquakes today at the fifth node from the Alaska Peninsula included the M 3.9 in England, quakes in Puerto Rico and Dominican Republic and an M 4.2 in Luzon, Philippines.

 

O:  8SEP2020 08:28:51  15.2S  172.9W Mw=5.4  EMSC   SAMOA ISLANDS REGION         

P:  5SEP2020 127007    17.0S  172.0W 4.0-5.6 BBAAA  Tonga Islands              

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the southern Idaho aftershock zone. It and an M 3.9 foreshock were reported by NEIC to have been felt with intensity up to V in Idaho at Cascade and III-IV in Stanley, Lowman, McCall, Garden Valley, Ketchum, Challis, Ellis, New Meadows and Garden City. This is the strongest aftershock of the M 6.5 in southern Idaho of March 31, 2020 since an M 4.6 on June 25, 2020. Other aftershocks of M>=4.4 have hit the area on May 14 and May 21, 2020. Today's event followed an M 3.9 half an hour earlier. No major damage was reported. Forecast 126935 had expected today's earthquake was likely around September 5.

 

O: 08SEP2020 16:32:46  44.3N  115.2W ML=2.9  EMSC   SOUTHERN IDAHO

O: 08SEP2020 20:38:02  44.4N  115.2W ML=3.2  EMSC   SOUTHERN IDAHO

O: 08SEP2020 12:24:14  44.4N  115.2W Ml=3.5  EMSC   SOUTHERN IDAHO

O: 08SEP2020 20:42:39  44.5N  115.2W ML=3.0  EMSC   SOUTHERN IDAHO

O: 08SEP2020 07:26:53  44.5N  115.2W Ml=2.7  EMSC   SOUTHERN IDAHO

O: 08SEP2020 20:24:29  44.5N  115.2W Mw=4.4  EMSC   SOUTHERN IDAHO

O: 08SEP2020 20:23:49  44.5N  115.2W mb=3.9  EMSC   SOUTHERN IDAHO

O: 08SEP2020 21:50:27  44.5N  115.3W ML=2.6  EMSC   SOUTHERN IDAHO

O:  8SEP2020 09:10:40  44.1N  115.1W Ml=2.0  EMSC   SOUTHERN IDAHO               

P:  5SEP2020 126935    44.5N  115.2W 2.0-4.2 BAAAA  Montana/Idaho              

 

 

 

 

 

 

STRONG QUAKE SHAKES BANDA SEA, INDONESIA

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  7, 2020

 

An earthquake of M 6.0-6.1 occurred today in the Banda Sea of Indonesia today. NEIC reported it was felt with intensity II-III in Sorong, Papua, Indonesia and in Darwin, Northern Territory, Australia. This continues activation of central Indonesia and southern Philippines which has included an M 6.4 in Mindanao and an M 6.3 in the Molucca Sea over the past two days. This is the strongest earthquake in the Banda Sea within about 200 km of this epicenter since an M 7.3 on June 24, 2019 about 150 km to the south. The last within about 150 km was an M 7.1 on December 10, 2012. Forecast 126821 had expected today's event within about 200 km was likely around September 8.

 

O:  8SEP2020 00:45:21   4.9S  129.8E Mw=6.1  EMSC   BANDA SEA                    

P:  8SEP2020 126821     3.0S  130.0E 4.0-5.6 ABAAA  West Irian, PNG            

 

An M 5.2 occurred today in the northern Ryukyu Islands, Japan. NEIC reported it was felt with intensity II-III in Okinawa at Nago, Ishikawa, Yomitan, Gushikawa, Okinawa, Chatan, Giniowan and Urasoe. This area has been in the path of several typhoons in the past week and had been expected in this summary to see enhanced seismicity at this time. For example when Super Typhoon passed over this epicenter on September 6, it was noted:

 

"Super-Typhoon Haishen (TD 11W) continued today north of the Ryukyu Islands, Japan with winds up to 115 kts. It is expected to track to the north reaching southern Honshu and Kyushu September 6-7. It could promote a moderate to strong earthquake in western Honshu or the Ryukyu Islands with or after landfall." (September 5-7, 2020)

 

This earthquake occurred within about an hour of local solar noon and may have been promoted by high tidal stresses which maximize near this hour. The last  event of M>=5.2 in the northern Ryukyu Islands was an M 6.7 on June 13, 2020 and prior to that  M 5.9 north of this on May 3, 2020. The last within about 200 km was an M 5.9 on May 3, 2020.  Forecast 126865 had expected today's event within about 100 km of this epicenter in the Ryukyu Islands around September 5.

 

O:  8SEP2020 02:58:14  27.0N  127.8E mb=5.2  EMSC   RYUKYU ISLANDS, JAPAN        

P:  5SEP2020 126865    28.0N  127.0E 4.0-5.4 BAAAA  Ryukyu Islands             

 

The strongest earthquake in the U.S. or Canada today occurred in the Northwest Territory of Canada near Banks Island where it was not reported felt. Forecast 126991 had expected activity within about 200 km of this epicenter was likely  around September 6.  This is the largest earthquake within about 200 km of this epicenter since an M 4.2 west of this on July 15, 2017 and an M 4.3 on April 24, 2012. The strongest earthquake in the area in the past 30 years was an M 4.8 on August 13, 1992.  This epicenter is near 103 degrees from the Banda Sea quake of August 21 (M 6.9) and Sumatra of August 18 (M 6.8) and was probably promoted by energy from that source.

 

O:  8SEP2020 03:56:43  71.8N  127.0W mb=4.1  EMSC   BANKS ISLAND, NW TERR., CANADA

P:  6SEP2020 126991    70.0N  131.0W 2.5-4.0 ABAAA  Yukon Territory, Canada    

 

A series of moderate earthquakes including an M 5.4 in Guam occurred in the Mariana Islands today. These were not reported felt but the M 5.4 was probably felt in Guam. Forecasts 126843 and 126850 had expected this activity was likely

in early September. This activity is near 144 degrees from the M 7.0 in Atacama,

Chile of September 1 and was probably promoted by energy from that source. Other earthquakes today at this distance from Atacama, Chile occurred in Java (M 4.6); south of Sumatra (M 4.6, 4.8); Gujarat, India (M 3.1, 3.8); and Uzbekistan (M 4.8).

 

O:  7SEP2020 18:44:31  17.1N  147.5E mb=4.6  EMSC   MARIANA ISLANDS REGION       

P:  4SEP2020 126843    19.0N  147.0E 4.0-5.5 BBAAA  No. Marianas               

 

O:  8SEP2020 00:54:06  13.2N  144.4E mb=5.4  EMSC   GUAM REGION                  

P:  7SEP2020 126850    13.0N  145.0E 4.0-5.6 AAAAA  So. Marianas/Guam          

 

O:  7SEP2020 07:32:32  14.1N  146.6E mb=4.8  EMSC   ROTA REGION, N. MARIANA ISLAND

P:  7SEP2020 126850    13.0N  145.0E 4.0-5.6 ABBAA  So. Marianas/Guam          

 

STRONG EARTHQUAKES CONTINUE IN VANUATU AND MINDANAO, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  6, 2020

 

The group of strong earthquakes detailed in this summary in the previous issue continued today with additional strong events of M 6.2 and 5.9 in Vanuatu and M 6.4 in Mindanao, Philippines today. Most seismic areas of the world today also saw enhanced seismicity with moderate earthquake abundant. These included the northern and southern area of the Atlantic region.

 

The earthquake of M 6.2 in Vanuatu is east of  the location as an M 6.3 yesterday and was also felt, like that event, with intensity III in Vila Shefa, Vanuatu according to data from NEIC. This series was discussed in the previous issue of this report as:

 

 

"The M 6.2 in Vanuatu was reported by NEIC to have been felt with intensity IV in Vila Shefa, Vanuatu. It was accompanied by aftershocks of M 4.9, 5.1 and 5.2. It occurred in an area of active volcanism and may have been related to that. The last shallow focus earthquake within about 250 km of this epicenter in the Vanuatu Islands with M>=6.2 was an M 6.5 on August 21, 2018 and prior to that an M 7.0 on April 28, 2016. Forecast 127011 had expected today's event within about 25 km was likely around September 7. This epicenter is at 103-105 degrees from the earthquake of M 7.0 in Atacama, Chile of September 1 and from the M 6.3 in Coquimbo, Chile today  and from the M 7.4 in Oaxaca, Mexico of June 23 and was probably promoted by energy from those sources." (September 5-6, 2020)

 

The epicenter of today's M 6.2 is more than 50 km to the northeast of the M 6.2 yesterday in the Vanuatu Islands. It is the strongest earthquake in this area of the Vanuatu Islands east of 168 East longitude since an M 6.8 on January 23, 2015. Forecast 127011 had expected today's activity was likely around September 7.

 

O: 07SEP2020 06:12:41  17.1S  168.4E Mw=6.2  EMSC   VANUATU

O: 07SEP2020 06:29:15  17.2S  168.5E Mw=5.7  EMSC   VANUATU

O:  7SEP2020 04:41:27  17.0S  167.8E mb=5.0  EMSC   VANUATU                       

P:  7SEP2020 127011    17.0S  168.0E 4.0-5.5 AAAAA  Vanuatu Islands            

 

The earthquake of M 6.3 in southern Mindanao, Philippines was also widely felt today. Damage was reported with intensity VII in Southern Mindanao at Kapuan and Buayan, with V in Ilangay and Sarangani and IV shaking at Polomolok, Bato and Davao. Lesser intensities were reported from Silway, Camudmud and Ula, Southern Mindanao, Philippines. An M 6.4 hit Mindanao about 200 km northwest of this epicenter on August 1, 2020 but the last such event within 200 km was an M 6.6 on October 29, 2019 and an M 6.8 on December 15, 2019. Today's event is probably a regional aftershock of the December 15, 2019 event. Forecast 126797 had expected today's event within about 100 km of this epicenter was likely around September 6.

 

O:  6SEP2020 15:23:42   6.4N  125.7E Mw=6.4  EMSC   MINDANAO, PHILIPPINES        

P:  6SEP2020 126797     6.0N  125.0E 4.0-5.5 AAAAA  Mindanao, Philippines      

 

Two light earthquakes of M 2.8 and 3.2 were widely felt in the area of San Francisco, California today. NEIC reported maximum intensity III in San Leandro, San Lorenzo, Hayward, Castro Valley, Oakland, among others. The last earthquake in the San Francisco Bay area with M>=3.2 within about 50 km of today's epicenter on the Hayward Fault was an M 4.5 on October 15, 2019. Forecast 126877 had expected today's activity in this area was likely around September 9.

 

O:  6SEP2020 18:36:03  37.7N  122.1W Md=2.6  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O:  6SEP2020 18:43:57  37.7N  122.1W Mw=3.2  EMSC   SAN FRANCISCO BAY AREA, CALIF.

P:  9SEP2020 126877    37.8N  122.6W 2.5-4.4 BAAAA  Central California         

 

The strongest earthquakes in the U.S. or Canada today were a pair of M 4.4 events in the Andreanof Islands, Alaska. This area has been active with events up to M 4.7 over the past week. Several of the events in this swarm have been felt at Adak, Alaska. Forecast 126961 had expected today's activity in the Andreanof Islands was likely around September 5.

 

O: 06SEP2020 18:19:26  51.2N  179.7W mb=4.4  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 06SEP2020 17:30:52  51.3N  178.9W mb=4.4  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O:  6SEP2020 18:39:10  51.1N  179.7W mb=4.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  5SEP2020 126961    50.8N  175.8W 3.5-4.9 AACAA  Andreanoff Isls, Aleutians 

 

An earthquake of M 4.3 was also recorded on the island of Hawaii today.

NEIC reported this earthquake of M 3.4-4.3 in Hawaii  was felt with intensity II-III in the area(s) of Hawaii at Pahala (IV), Naalehu, Captain Cook, Volcano, Holualoa, Hilo, Panoa, Kealakekua, Paauilo and Hakalau. An M 4.2 occurred near this epicenter on August 16, but the last event in Hawaii of larger or equal magnitude was an M 4.4 on August 1, 2020. Forecast 126833 had expected today's event was likely around September 5.

 

O:  6SEP2020 12:19:45  19.2N  155.5W ML=4.3  EMSC   ISLAND OF HAWAII, HAWAII     

P:  5SEP2020 126833    19.3N  155.1W 3.0-4.5 AAAAA  Hawaii                     

 

High latitude ocean ridges continued at active conditions today. Moderate

earthquakes were located in the South Atlantic in the Scotia Sea (M 4.7); Falkland Islands (M 5.0) and the South Shetland Islands (M 4.7) and in the north Atlantic in Iceland and the Reykjanes Ridge (M 4.4, 4.4). This activity follows several days of enhanced seismicity in these regions and had been expected in forecasts 127050 and 126968 in early September.

 

O:  7SEP2020 00:01:17  57.1S   54.9W mb=4.7  EMSC   SCOTIA SEA                   

O:  7SEP2020 00:01:58  52.3S   55.3W mb=5.0  EMSC   FALKLAND ISLANDS REGION      

P:  5SEP2020 127050    62.0S   54.0W 3.0-5.9 ACAAA  So. So. America            

 

O:  6SEP2020 07:36:18  60.7N   28.7W mb=4.4  EMSC   REYKJANES RIDGE              

O:  6SEP2020 15:17:09  60.8N   28.5W mb=4.4  EMSC   REYKJANES RIDGE              

P:  8SEP2020 126968    59.0N   31.0W 4.0-5.4 ABBAA  North Mid-Atlantic Ridge   

 

O:  7SEP2020 00:00:42  62.4S   58.5W mb=4.7  EMSC   SOUTH SHETLAND ISLANDS       

P:  5SEP2020 127050    62.0S   54.0W 3.0-5.9 AABAA  So. So. America            

 

O:  7SEP2020 06:21:09  63.9N   22.1W ML=3.3  EMSC   ICELAND REGION               

P:  5SEP2020 126984    65.0N   22.0W 3.0-4.8 ABAAA  Iceland area               

 

 

STRONG EARTHQUAKES HIT MANY AREAS

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  5, 2020

 

A series of strong earthquakes hit around the world today. These included events in the Mid-Atlantic of M 5.3 and 6.6; in Vanuatu of M 6.2; in Coquimbo, Chile of M 6.3 and in Molucca, Indonesia of M 6.0. Much of today's activity followed on the full moon of September 1 and the geomagnetic storm which occurred in early September and had been anticipated as a continuation of the enhanced activity in mid-ocean ridges and near 80 West longitude in previous issues of this summary as:

 

 

"The earthquakes in Panama suggest the effect of the full moon is not yet complete. The area to watch for the next several days continues to be the western coast of South America in the region of Chile. The area at 103-108 degrees from the Atacama event in Chile of M 7.0 on September 1 is in the region of Vanuatu where a moderate to large earthquake is also possible in the near term." (September 4-5, 2020)

 

and

 

"Ocean Ridges remained active today with moderate quake southwest of Africa (M 5.0); in the South Shetland Islands (M 5.0; the South Sandwich Islands (M 4.9) and the Owen's Fracture Zone (M 4.5, 4.5). The activation of ocean ridges began with the strong geomagnetic storm of the past several day, an event which is now in decline." (September 4, 2020)

 

The strongest earthquake in the world today was an  M 6.6 in the Central Mid-Atlantic Ridge. It was not reported felt in this remote area. This is the strongest earthquake within about 250 km of this epicenter since an M 6.6 on September 10, 2008, the only such event in the area in the past 30 years. Forecast 126789 had expected a moderately large regional event in this area was likely around September 7. This epicenter is at 101 degrees from the M 7.8 in the Alaska Peninsula of July 22 and was probably promoted by energy from that source.

 

O:  6SEP2020 06:51:21   7.7N   37.2W Mw=6.6  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P:  7SEP2020 126789     7.0N   35.0W 4.0-5.8 AABAA  Central Mid-Atlantic Ridg  

 

The M 6.6 in the Central Mid-Atlantic Ridge followed an M 5.2-5.3 in the Northern Mid-Atlantic Ridge by 13 minutes. It may have been triggered by surface waves and/or S-phase waves from the northern Atlantic event 40 degrees to the north as these were in the area when the M 6.6 occurred. The earthquake in the northern Mid-Atlantic is the strongest within about 250 km of that epicenter since an M 5.4 on September 30, 2013. The strongest in the past 30 years in the area was an M 5.9 on December 19, 2008. Forecast 126941 had expected a moderate earthquake in this area of the northern Mid-Atlantic was likely around September 4.

 

O:  6SEP2020 06:38:35  47.8N   27.5W mb=5.2  EMSC   NORTHERN MID-ATLANTIC RIDGE  

O:  6SEP2020 06:38:35  47.7N   27.5W mb=5.3  ANSS   NORTHERN MID-ATLANTIC RIDGE  

P:  4SEP2020 126941    45.0N   28.0W 4.0-5.6 ACAAA  No. Mid-Atlantic Ridge     

 

The M 6.2 in Vanuatu was reported by NEIC to have been felt with intensity IV in Vila Shefa, Vanuatu. It was accompanied by aftershocks of M 4.9, 5.1 and 5.2. It occurred in an area of active volcanism and may have been related to that. The last shallow focus earthquake within about 250 km of this epicenter in the Vanuatu Islands with M>=6.2 was an M 6.5 on August 21, 2018 and prior to that an M 7.0 on April 28, 2016. Forecast 127011 had expected today's event within about 25 km was likely around September 7. This epicenter is at 103-105 degrees from the earthquake of M 7.0 in Atacama, Chile of September 1 and from the M 6.3 in Coquimbo, Chile today  and from the M 7.4 in Oaxaca, Mexico of June 23 and was probably promoted by energy from those sources.

 

O: 06SEP2020 04:20:50  17.1S  167.8E mb=5.1  EMSC   VANUATU

O: 06SEP2020 04:39:23  17.1S  167.7E mb=5.2  EMSC   VANUATU

O: 06SEP2020 03:44:25  17.2S  167.7E mb=4.9  EMSC   VANUATU

O:  6SEP2020 02:59:15  17.1S  167.8E Mw=6.2  EMSC   VANUATU                      

P:  7SEP2020 127011    17.0S  168.0E 4.0-5.5 AAAAA  Vanuatu Islands            

 

The M 6.3 in Coquimbo, Chile was not an aftershock of the Atacama event of September 1, 2020 but may have been affected by stress redistribution from that event which occurred about 200 km to the north of today's event. Today's event was reported with intensity V in Coquimbo at Ovalle, Andacollo, Coquimbo, La Serena, and in Valparaiso, Chile. Intensity IV was reported in La Ligua with II-III in Illapel, Vina del Mar, Villa Alemana, Valparaiso and in San Juan, Argentina. GUC reported this earthquake was felt with intensity   VI in  Coquimbo at Coquimbo and La Serena; V in Andacollo, Canela, Paiguano, Punitaqui, Vicuna; IV in Rio Hurtado, Ovalle, Monte Patria, La Higuera, Illapel, and Combarbala; in Atacama with V in Vallenar and IV in Alto del Carmen, Copiapo, Freirina, Huasco and Tierra Amarilla; in Valparaiso with V at Valparaiso; IV in Llaillay, Papudo, Vina del Mar ; III in San Felipe and II in Villa Alemana and Limache; in Valparaiso with IV in Colina, Puente Alto Penalolen, III in Lampa, Santiago, La Reina, Los Condes, Lo Barnechea, San Miguel, Pudahuel, Macul, Pedro Aguirre Cerda; in O'Higgins with III in Codegua and Mostazal, Chile.\ Today's M 6.3 is the strongest earthquake in the Coquimbo, Chile area within about 150 km of this epicenter since an M 6.4 on June 14. 2019. Both are probably aftershocks of an M 6.7 on January 29, 2019.  Forecast 127027 had expected today's earthquake was likely within this area around September 4. This epicenter is at 144 degrees from the M 7.0 in Sumatra of August 18 and was probably promoted by energy from that source as well as by redistributed stress from the Atacama M 7.0 of September 1. Other earthquakes of 144 degrees from Sumatra today included an M 2.2 in Oklahoma and a series of M 3.4, 3.8 and 3.4 in the Gulf of California.

 

O:  6SEP2020 01:16     30.4S   71.4W mb=6.3  GUC    Coquimbo at Coquimbo and La Se

O: 06SEP2020 01:16:57  30.4S   71.5W Mw=6.3  EMSC   COQUIMBO, CHILE

O: 06SEP2020 01:20:19  30.4S   71.5W ML=4.4  EMSC   COQUIMBO, CHILE

P:  4SEP2020 127027    31.0S   72.0W 4.0-5.9 AAAAA  Central Chile              

 

An M 5.9-6.0 in the Molucca Sea of Indonesia was reported by NEIC to have been felt with intensity II in Manado, Sulawesi. The area has been active in the past several weeks, but the last earthquake within about 200 km of today's epicenter in the Molucca Sea occurred on November 14, 2019 with M 7.1 and 6.0. Today's event appears to be the largest aftershock of that M 7.1 to date.  Forecast 126517 had expected today's event was likely within this area at the end of August or in early September.

 

O:  6SEP2020 00:21:11   1.7N  126.6E Mw=6.0  EMSC   MOLUCCA SEA                  

P: 31AUG2020 126517     3.0N  127.0E 4.0-5.5 ACBAA  Halmahera                  

 

An earthquake of M 3.8 followed the event in Coquimbo, Chile west of Los Angeles, California. NEIC reported this unusual event was felt with intensity II-III in southern California at Solvang, Goleta, Santa Ynez, Los Olivos, Buellton, Santa Barbara and Lompoc. This epicenter is at 79 degrees from and 33 minutes after Coquimbo. Seismic waves from that source such as SSS and surface phases may have helped trigger the event in southern California. This is the strongest earthquake in the region within about 100 km and west of Santa Barbara since an M 3.8 on January 7, 2018. Forecast 126905 had expected today's event near Santa Barbara around September 4. Aftershocks of M 2.4 and 2.1 followed the mainshock.

 

O: 06SEP2020 03:39:51  34.6N  120.1W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 06SEP2020 04:01:40  34.6N  120.1W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O:  6SEP2020 01:48:31  34.4N  120.3W ML=3.6  EMSC   SANTA BARBARA CHANNEL, CALIF.

O:  6SEP2020 01:48:31  34.4N  120.3W ML=3.8  ANSS   SANTA BARBARA CHANNEL, CALIF.

P:  4SEP2020 126905    34.7N  119.0W 2.5-4.4 AAAAA  So. California             

 

An unusual earthquake in Maui, Hawaii also occurred today. NEIC reported it was widely felt in Maui with maximum intensity IV in Hawaii at Hana and II-III in Kaunakakai, Lahaina, Kula, Wailuku, Kihei, Kahului, Haiku, Paia, Makawao. This event of M 3.6-3.8 is the strongest in the region of Maui since an M 3.7 two years ago on September 15, 2018 and an M 4.0 on September 28, 2018. Forecast 126857 had expected today's event near Maui, Hawaii was likely around September 5. This epicenter is at 103 degrees from the M 7.0 in Sumatra of August 18 and was probably promoted by energy from that source.

 

O:  5SEP2020 07:43:16  20.9N  156.3W ML=3.6  EMSC   MAUI REGION, HAWAII          

O:  5SEP2020 07:43:16  20.9N  156.3W ML=3.8  ANSS   MAUI REGION, HAWAII          

P:  5SEP2020 126857    20.1N  156.1W 4.0-5.5 AAAAA  Hawaii area                

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in the Alaska Peninsula. NEIC reported this earthquake of M 3.6-4.1 in the Alaska Peninsula  was felt with intensity II-III in the area(s) of the Alaska Peninsula at Chignik. This is about 200 km northeast of the M 7.8 mainshock of July 22 and is not part of the classical aftershock sequence in the area. Most moderate aftershocks have been occurring west of the mainshock epicenter. The last earthquake within about 100 km of today's event with M>4.1 was an M 4.7 on February 17, 2020 and prior to that an M 4.4 on February 1, 2020. Forecast 126960 had expected today's event was likely in this area around September 4.

 

O:  5SEP2020 12:43:38  55.0N  158.3W ML=3.0  EMSC   ALASKA PENINSULA             

O:  5SEP2020 08:20:27  56.8N  156.9W mb=4.1  EMSC   ALASKA PENINSULA             

P:  4SEP2020 126960    54.8N  159.6W 3.5-5.4 AABAA  Alaska Peninsula           

 

 

 

 

 

MODERATELY STRONG QUAKES IN PANAMA

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  4, 2020

 

The strongest earthquake in the world today was an M 5.6 in Panama. NEIC reported it was felt with intensity VI in Panama at Puerto Armuelles, Rio Sereno, and VII in Los Algarrbos, Chirqui; IV in Volcan, Quiteno, and II-III in Golfito, David, Palmira, Bouquete, and Almirante Bocas del Toro. An aftershock of M 5.3 was reported felt with intensity III in Panama at Guarumal, Potrerillos Abajo, Puerto Nuevo and Volcan, Chiriqui. Like much of the stronger activity in the world in the past three days, this event occurred near 80 degrees west longitude and was apparently  promoted by strong tidal stresses associated with the full moon of September 2 as noted in previous issues of this summary:

 

"The full moon arrived at 05:22 UT on September 2, 2020. Longitudes which were at local solar midnight at this time are near 80 West while those at solar noon are near 100 East. These include in the west, Central America and western South America and in the east Sumatra and western Indonesia and southeast Asia. These regions are likely to see moderate seismic with this full moon. Tidal triggering is not usually major at full moon but can occur  - normally near local solar midnight and noon in areas where seismicity is controlled by vertical tectonics and/or fluid motions." (September 1-3, 2020)

 

The earthquakes in Panama suggest the effect of the full moon is not yet complete. The area to watch for the next several days continues to be the western coast of South America in the region of Chile. The area at 103-108 degrees from the Atacama event in Chile of M 7.0 on September 1 is in the region of Vanuatu where a moderate to large earthquake is also possible in the near term.

 

The last earthquake within about 150 km of today's M 5.6 in Panama was an M 6.2 on June 26, 2019. Forecasts 126515 and 126793 had expected today's activity was likely within about 50 km of this epicenter in late August or early September. Today's activity is near the antipode of the M 7.0 in Sumatra of August 18, 2020 and may have been promoted by antipodal focusing of energy from that event.

 

O: 04SEP2020 17:58:30   8.3N   83.0W ML=4.1  EMSC   COSTA RICA

O: 04SEP2020 20:03:30   8.3N   83.0W ML=4.4  EMSC   COSTA RICA

O: 04SEP2020 23:29:30   8.3N   83.0W ML=4.0  EMSC   COSTA RICA

O: 04SEP2020 23:56:30   8.3N   83.0W ML=4.6  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 05SEP2020 05:21:30   8.3N   83.0W ML=4.1  EMSC   COSTA RICA

O: 05SEP2020 05:38:14   8.3N   82.9W mb=4.5  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 04SEP2020 17:45:21   8.4N   83.0W Mw=5.5  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 04SEP2020 17:45:21   8.4N   83.0W Mw=5.6  ANSS   PANAMA-COSTA RICA BORDER REGION

O: 04SEP2020 17:46:43   8.4N   82.8W mb=5.3  EMSC   PANAMA-COSTA RICA BORDER REGION

O:  4SEP2020 17:48:53   8.4N   83.0W mb=4.9  EMSC   PANAMA-COSTA RICA BORDER REGIO

P:  7SEP2020 126793     9.0N   85.0W 3.5-5.3 BABAA  Costa Rica                 

P: 28AUG2020 126515     8.0N   83.0W 3.5-4.9 CAAAA  Costa Rica                  

 

The strongest earthquake in the U.S. or Canada today was an M 4.6 in the western Andreanof Islands, Aleutians, Alaska. It was reported with intensity III felt in Adak, Alaska. This is the third such event in the Andreanof Islands region in the past three days. Previous events were reported in the last issue of this summary as:

 

"The strongest earthquake in the U.S. or Canada today was an M 4.4 in the western Andreanof Islands, Aleutians, Alaska. This is the second such event in the area in the past two days. This summary noted the previous in yesterday's summary. The last earthquake with M>=4.4 in the Andreanof Islands occurred on July 22, 2020 with M 4.9. Forecast 126691 had expected today's activity was likely at the end of August or early September.

 

NEIC reported this earthquake of M 4.4 in the Andreanof Islands, Alaska  was felt with intensity II-III in the area(s) of the Andreanof Islands, Alaska at Adak." (September 3-4, 2020)

 

Forecast 126961 had expected this event of M 4.7 was likely around September 5.

This activity is located at the third node (120 degrees) from the M 7.0 in

Atacama, Chile of September 1 and may have been promoted by energy from that source.

 

O:  5SEP2020 05:14:51  51.7N  178.5W mb=4.7  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  5SEP2020 126961    50.8N  175.8W 3.5-4.9 AABAA  Andreanoff Isls, Aleutians 

 

Antipodal activity at moderate levels continued today in the South Sandwich Islands (M 4.7) and as a swarm in the region of Kamchatka. This antipodal activity began several days ago and may involve some volcanic activity in Kamchatka. This was first reported in this summary on September 1 as:

 

 

"An antipodal pair of earthquakes occurred today - first in the South Sandwich Islands with M 4.8 and about an hour-and-a-half later as an M 5.6 in Kamchatka, Russia. These events are not uncommon but illustrate the impact that geomagnetic storms can have on antipodal seismicity. The Kamchatka event occurred within about 30 minutes of local solar noon while the South Sandwich event occurred near local solar midnight. Both may also have been affected by strong tidal stresses associated with the full moon which maximize at these hours. The event in the South Sandwich Islands had been expected in forecast 126786 to occur around August 27. (September 1, 2020)

 

Today's event in the South Sandwich Islands occurred near local solar noon and may have been promoted by tidal stresses which maximize at this hour. Forecast 127049 had expected this activity within about 50 km of the epicenter was likely around September 8.

 

O:  4SEP2020 11:49:35  55.4S   27.4W mb=4.9  EMSC   SOUTH SANDWICH ISLANDS REGION

P:  8SEP2020 127049    55.0S   28.0W 4.0-5.7 BAAAA  So. Sandwich Islands       

 

The activity in the region of Kamchatka also occurred near local solar noon

and may have been tempered by tidal stresses. Forecast 126965 had expected

this activity in Kamchatka around September 5.

 

O: 04SEP2020 23:01:51  52.2N  160.3E mb=4.3  EMSC   OFF EAST COAST OF KAMCHATKA

O: 05SEP2020 00:21:26  52.3N  160.0E mb=4.6  EMSC   OFF EAST COAST OF KAMCHATKA

O: 04SEP2020 21:14:26  52.4N  159.9E mb=4.7  EMSC   OFF EAST COAST OF KAMCHATKA

O: 04SEP2020 21:50:21  52.5N  160.1E mb=4.4  EMSC   OFF EAST COAST OF KAMCHATKA

O:  4SEP2020 21:10:13  52.2N  160.2E mb=4.8  EMSC   OFF EAST COAST OF KAMCHATKA  

P:  5SEP2020 126965    52.0N  158.0E 4.0-5.9 AABAA  Kamchatka                  

 

A moderate earthquake of M 5.0 shook the northern Ryukyu Islands of Japan today.

This is the strongest earthquake in the Ryukyu Islands within about 250 km of  this epicenter since an M 6.6 on June 13, 2020 and an M 5.2 on January 6, 2020.

Forecasts 126591 and 126859 had expected this activity in early September. Typhoon Maysak passed over this epicenter two days ago and stresses associated with this typhoon probably helped trigger today's activity as noted in previous issues of this report:

 

"Typhoon Maysak (TD 10W) continued today over the Ryukyu Islands with winds up to 150 kts. It is expected to track to the north and west and could enhance seismicity in the  Ryukyu Islands in the next several days." (September 1-2, 2020)

 

O:  4SEP2020 19:36:21  29.3N  130.6E Mw=5.0  EMSC   RYUKYU ISLANDS, JAPAN        

P:  1SEP2020 126591    29.0N  129.0E 4.0-5.4 BAAAA  Ryukyu Islands             

P:  8SEP2020 126859    29.0N  131.0E 4.0-5.4 BAAAA  Kyushu Japan               

 

LIGHT EARTHQUAKE SHAKES ALABAMA AND FLORIDA

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  3, 2020

 

An unusual M 3.8 shook areas of Alabama and Florida today. NEIC gave maximum intensity IV in Jay, Florida and II-III in Florida at Century, Milton, Contonment, Holt, and in Alabama at Flomaton, Brewton, Almore. This epicenter is near where Hurricane Laura made landfall this week and many have been promoted by energy from that event. This event at 87W longitude also confirms the likely role of tidal effects from the full moon in the occurrence of this earthquake at this time. The tidal seismicity forecast in this summary had read:

 

"The full moon arrived at 05:22 UT on September 2, 2020. Longitudes which were at local solar midnight at this time are near 80 West while those at solar noon are near 100 East. These include in the west, Central America and western South America and in the east Sumatra and western Indonesia and southeast Asia. These regions are likely to see moderate seismic with this full moon. Tidal triggering is not usually major at full moon but can occur  - normally near local solar midnight and noon in areas where seismicity is controlled by vertical tectonics and/or fluid motions." (September 1-3, 2020)

 

The last earthquake in Alabama within about 200 km of this epicenter with M>=3.8 occurred on June 30, 2015 and November 20, 2014 (both with M 3.8). Two other such events have occurred in this area in the past 30 years - an M 4.3 on November 7, 2004 and an M 4.9 on October 24, 1997. Forecast 126644 had expected regional activity enhancement at the end of August or in early September. This epicenter is at the sixth node (60 degrees) from  the M 7.0 in Atacama, Chile of September 1 and was probably promoted by energy from that source.

 

O:  3SEP2020 15:07:53  31.0N   87.2W Mw=3.8  EMSC   ALABAMA                      

P: 31AUG2020 126644    34.0N   85.0W 2.0-4.1 BCBAA  Southeast U.S.             

 

The strongest earthquake in the world today was an M 5.0-5.7 in northern South Island, New Zealand. GEONET reported this earthquake was felt with moderate intensity in northern South Island. 25279 people reported feeling this event; 12184 with weak intensity; 10960 with light shaking; 1954 moderate; 145 strong; 12 with severe and 24 with extreme shaking. NEIC reported this earthquake of M 4.7 in South Island, New Zealand was felt with intensity II-III in the area(s) of South Island, New Zealand at Culverden, Canterbury.  A light foreshock about 50 km northeast of this of M 4.0 occurred on August 30, 2020. The last earthquake within about 200 km of this epicenter with M>=5.2 was an M 5.4 on January 5, 2107. The last of larger magnitude was an M 6.5 on November 13-14, 2016. Forecast 127044 had expected today's activity was likely within about 100 km of the epicenter around September 5. This earthquake is at the fourth node (90 degrees) from the Atacama quake of September 1, 2020 and at 100-102 degrees from the M 7.5 in Oaxaca, Mexico of June 23, 2020 and the Alaska Peninsula quake of M 7.8 on July 22, 2020. Seismic energy is concentrated at this distance on the surface following large event and can help promote enhanced seismicity at this distance. Other moderate earthquakes at this distance from Oaxaca today occurred in Honshu, Japan (M 5.0, 5.0, 5.3) and in Greece (M 4.3).

 

O: 03SEP2020 10:13:00  41.8S  172.7E ML=5.7  GEONET Felt with moderate intensity

O:  3SEP2020 10:12:59  41.8S  172.7E Mw=5.2  EMSC   SOUTH ISLAND OF NEW ZEALAND  

P:  5SEP2020 127044    42.0S  174.0E 3.0-5.2 AAAAA  So. Island, N.Z.           

 

Ocean Ridges remained active today with moderate quake southwest of Africa (M 5.0); in the South Shetland Islands (M 5.0; the South Sandwich Islands (M 4.9) and the Owen's Fracture Zone (M 4.5, 4.5). The activation of ocean ridges began with the strong geomagnetic storm of the past several day, an event which is now in decline. The M 5.0 southwest of Africa is near the antipode of the  M 7.8 and aftershocks in the Alaska Peninsula of July 22 and was probably promoted by focused energy from that source.

 

O:  4SEP2020 03:23:37  52.5S   13.6E mb=5.0  EMSC   SOUTHWEST OF AFRICA          

 

The M 4.9 in the South Sandwich Islands is at 103 degrees from the M 7.0 in

Sumatra of August 18 and was probably promoted by energy from that source.

 

O:  3SEP2020 22:52:19  60.4S   25.4W mb=4.9  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 31AUG2020 126787    61.0S   26.0W 4.0-5.6 BAAAA  Southern  Ocean            

 

O:  3SEP2020 23:29:39  62.4S   58.2W Mw=5.0  EMSC   SOUTH SHETLAND ISLANDS       

P:  5SEP2020 127050    62.0S   54.0W 3.0-5.9 ABAAA  So. So. America            

 

The activity in the Owen Fracture zone is at 104 degrees from the M 7.8 in

the Alaska Peninsula of July 22 and was probably promoted by concentrated

energy from that source.

 

O: 03SEP2020 20:40:43  14.4N   56.4E mb=4.5  EMSC   OWEN FRACTURE ZONE REGION

O: 03SEP2020 20:25:25  14.5N   56.3E mb=4.5  EMSC   OWEN FRACTURE ZONE REGION

O:  3SEP2020 20:36:55  14.4N   56.3E mb=4.3  EMSC   OWEN FRACTURE ZONE REGION    

P: 31AUG2020 126549    15.0N   56.0E 3.5-4.9 BAAAA  Arabian Sea                

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the western

Andreanof Islands, Aleutians, Alaska. This is the second such event in the area in the past two days. This summary noted the previous in yesterday's summary.

The last earthquake with M>=4.4 in the Andreanof Islands occurred on July 22, 2020 with M 4.9.  Forecast 126691 had expected today's activity was likely at the end of August or early September.

 

NEIC reported this earthquake of M 4.4 in the Andreanof Islands, Alaska  was felt with intensity II-III in the area(s) of the Andreanof Islands, Alaska at Adak.

 

O:  3SEP2020 23:35:57  51.3N  178.6W mb=4.4  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 28AUG2020 126691    51.7N  176.4W 3.5-4.9 BABAA  Andreanoff Isls, Aleutians 

 

SEISMIC ENHANCEMENT NEAR 80 WEST LONGITUDE

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  2, 2020

 

Seismic enhancement was observed near 80 degrees West longitude today in Colombia, Panama and Costa Rica. This was expected in the tidal seismicity forecast of this summary in previous issues as:

 

"The full moon will arrive at 05:22 UT on September 2, 2020. Longitudes which are at local solar midnight at this time are near 80 West while those at solar noon are near 100 East. These include in the west, Central America and western South America and in the east Sumatra and western Indonesia and southeast Asia. These regions are likely to see moderate seismic with this full moon. Tidal triggering is not usually major at full moon but can occur  - normally near local solar midnight and noon in areas where seismicity is controlled by vertical tectonics and/or fluid motions." (September 1, 2020)

 

The enhancement was joined by the low pressure unloading associated with

Tropical Storm Nana as reported in previous issues of this report:

 

"TS Nana formed today in the area north of Guatemala and Honduras with winds up to 50 kts. It is expected to track to the west over the next several days and will probably promoted seismicity in Guatemala and eastern Mexico in the next several days, including the possibility of a moderately large regional earthquake at this time." (September 1-2, 2020)

 

The largest of today's event occurred as an M 5.3 south of Panama at 79.9 West longitude. This was the second strongest earthquake in the world today following an M 5.4 in Papua New Guinea.  Forecasts 126515 and  126514 had expected this event was likely to the southeast of today's epicenter. The last earthquake of equal or greater magnitude in the area occurred with an M 5.3 on June 13, 2019 and an M 5.7 on January 31, 2018. Other moderate events in the region today occurred about 250 km north of this event with M 4.6 and about 300 km southeast in Colombia with M 4.5.  This activity is located at the antipode of the M 7.0 in Sumatra of August 18 and was probably also promoted by focused energy from that source.

 

NEIC reported this earthquake of M 5.3 in Panama  was felt with intensity IV in the area(s) of Panama at Panama City and I in Ancon.

 

O:  2SEP2020 21:09:24   6.2N   79.9W Mw=5.3  EMSC   SOUTH OF PANAMA              

P: 23AUG2020 126514     5.0N   78.0W 4.0-5.5 CBBAA  Colombia                   

 

 

NEIC reported the earthquake of M 4.5 in Costa Rica  was felt with intensity II-III in the area(s) of Puerto Armuelles, Panama.

 

O: 03SEP2020 05:39:30   8.3N   83.0W ML=4.1  EMSC   COSTA RICA

O: 03SEP2020 05:40:30   8.3N   83.0W ML=4.3  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 03SEP2020 05:29:55   8.4N   83.0W mb=4.5  EMSC   PANAMA-COSTA RICA BORDER REGION

O:  2SEP2020 18:49:39   7.7N   82.3W mb=4.6  EMSC   SOUTH OF PANAMA              

P: 28AUG2020 126515     8.0N   83.0W 3.5-4.9 BAAAA  Costa Rica                 

 

NEIC reported the earthquake of M 4.5 in  Colombia was felt with intensity II-III in the area(s) of Colombia at Turbo Antioquia.

 

O:  3SEP2020 03:23:37   8.2N   76.9W mb=4.5  EMSC   NEAR NORTH COAST OF COLOMBIA 

P: 31AUG2020 126514     7.0N   73.0W 4.0-5.4 BBCAA  Colombia                   

 

O:  2SEP2020 07:06:10  11.1N   86.9W mb=4.2  EMSC   NEAR COAST OF NICARAGUA      

P: 27AUG2020 126566    11.0N   86.0W 3.5-5.4 BAAAA  Nicaragua                  

 

 

A series of light earthquakes also occurred in the area of southern Baja California, Mexico and in the Gulf of California. These had been forecast in 126582 within about 100 km of these epicenters. This summary expected this activity with passage of Tropical Storms Iselle and Hernan through the region in late August as:

 

"TS Iselle continued today in the area south of the Gulf of California with winds up to 50 kts. It is expected to track to the north but not make landfall. Some moderate seismicity in the Gulf of California and Baja could be enhanced while Iselle is in the region." (August 29-30, 2020)

 

and

 

"TS Hernan continued today in the area south of the Gulf of California with winds up to 45 kts. It is expected to track to the north into the Gulf of California. Some moderate seismicity in the Gulf of California and Baja could be enhanced while Iselle is in the region." (August 29-30, 2020):45  24.1N  110.3W ML=2.9  EMSC   BAJA CALIFORNIA SUR, MEXICO

 

O: 02SEP2020 09:15:32  24.2N  110.3W ML=3.4  EMSC   BAJA CALIFORNIA SUR, MEXICO

O: 03SEP2020 02:45:22  24.2N  110.1W ML=3.3  EMSC   BAJA CALIFORNIA SUR, MEXICO

O:  2SEP2020 07:51:11  24.1N  110.3W ML=2.9  EMSC   BAJA CALIFORNIA SUR, MEXICO  

P: 31AUG2020 126582    24.0N  109.0W 3.5-5.0 AAAAA  Gulf of California         

 

NEIC reported the earthquake of M 3.3 in  the Gulf of California was felt with intensity II-III in the area(s) of the Gulf of California at La Paz, Baja California.

 

O:  2SEP2020 18:52:41  27.5N  111.3W ML=3.4  EMSC   GULF OF CALIFORNIA           

P: 27AUG2020 126582    28.0N  112.0W 3.5-4.9 BAAAA  Gulf of California         

 

The strongest earthquake in the U.S. or Canada today was an M 3.9 in the Northwest Territories of Canada. The last earthquake within about 100 km of this epicenter with M>=3.9 was and M 4.7 on July 25, 2020 with an aftershock of M 3.9 on August 13, 2020. Today's event is an aftershock in that series. Forecast 126724 had expected today's event within about 100 km of this epicenter was likely around August 31. This event is located at 101 degrees from the epicenter of M 7.0 in Atacama, Chile of September 1 and was probably triggered by strong concentrated  energy from that event.

 

O:  2SEP2020 07:43:42  61.9N  126.2W MB=3.9  ECAN Tungsten, NT                   

O:  2SEP2020 07:43:42  61.9N  126.2W ML=3.9  EMSC   NORTHWEST TERRITORIES, CANADA

P: 31AUG2020 126724    62.1N  124.2W 2.5-4.1 AAAAA  Northwest Terr., Canada    

 

The swarm of earthquake north of North Island, New Zealand continued at active levels today. The strongest events in this swarm today were M 4.4, 4.3 and 4.1. This was probably triggered by the strong geomagnetic storm of the past several days as this area has seen similar behavior with strong changes in the geomagnetic field in the past. This summary had noted when this swarm began:

 

 

"The series of earthquake off North Island, New Zealand continued today. The largest of today's events was an M 4.9 which occurred within about 15 minutes of local solar midnight and was probably promoted by tidal stresses which maximize at this hour and by geomagnetic effects from the current geomagnetic disturbance. In the prior issue of this summary it had been noted in regard to this series:

 

 

"The strongest earthquake in the world today was an M 5.5 north of North Island, New Zealand. NEIC reported it was felt with intensity V in New Zealand at Waihi and II-III in Pauanui Beach, Katikati, Bay of Plenty, Whitianga, Paeroa, Thames, Auckland and North Shore. ... It was accompanied by a series of lighter foreshocks and aftershocks beginning about 33 minutes before the mainshock. This may indicate volcanism was involved in this swarm. An M 5.8 hit near this same epicenter on November 23, 2019." (August 29, 2020)

 

and

 

"The geomagnetic field saw active conditions today. The AP level was 26.  High latitude geomagnetic field saw storm conditions with AP 42. This is the most disturbed the field has been in nearly a year since October 25-26, 2019 when the AP level reached 29 and 25 and high latitude AP reached 62. Strong seismic enhancement is likely with this storm especially near the geomagnetic equator and at high latitudes during the next four days." (August 31, 2020)

 

This activity is at the fourth node (90 degrees) from the Atacama quake of September 1, 2020 and may have been enhanced by energy from that source.

 

O: 02SEP2020 21:18:21  36.8S  177.2E ML=3.6  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 02SEP2020 22:09:51  36.8S  177.1E ML=3.8  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 02SEP2020 22:13:07  36.8S  177.0E ML=3.4  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 03SEP2020 01:04:53  36.8S  177.1E ML=3.8  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 03SEP2020 02:22:37  36.8S  177.1E ML=3.8  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 03SEP2020 02:26:08  36.8S  177.1E ML=3.5  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 03SEP2020 05:19:39  36.8S  177.1E ML=3.6  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 02SEP2020 07:28:15  36.9S  177.1E ML=4.1  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 02SEP2020 09:45:59  36.9S  177.1E ML=3.9  EMSC   OFF E. COAST OF N. ISLAND, N.Z.

O: 02SEP2020 19:46:23  37.0S  176.8E ML=4.3  EMSC   NORTH ISLAND OF NEW ZEALAND

O:  2SEP2020 19:45:00  36.8S  177.1E ML=4.4  EMSC   OFF E. COAST OF N. ISLAND, N.Z

P:  4SEP2020 127035    37.0S  178.0E 3.0-4.7 AAAAA  North Island, N.Z.         

P: 30AUG2020 126770    37.0S  178.0E 3.0-4.5 AAAAA  North Island, N.Z.         

 

An unusual earthquake of M 4.8 occurred north of New Zealand today as well. No similar events have occurred within about 300 km of this epicenter in the past 30 years. The last earthquake near 300 km of this epicenter with M>=4 was an M 4.8 on September 13, 1993.

 

O:  2SEP2020 18:42:44  31.2S  174.0E ML=4.8  EMSC   NORTH OF NEW ZEALAND         

 

The strongest earthquake in the world today was an M 5.4 in Papua New Guinea, Indonesia. NEIC reported this earthquake of M 5.4 in Papua, Indonesia  was felt with intensity II-III in the area(s) of Papua, Indonesia at Kiunga Fly River, PNG. The last earthquake of larger magnitude within about 200 km of this epicenter was an M 5.7 on April 26, 2016 with M 5.7. Forecast 126538 had expected today's activity in late August.

 

O:  2SEP2020 23:25:37   5.4S  140.4E mb=5.4  EMSC   PAPUA, INDONESIA             

P: 23AUG2020 126538     4.0S  140.0E 4.0-5.4 CBAAA  Papua New Guinea           

 

 

 

 

 

 

 

 

 

STRONG AFTERSHOCKS CONTINUE IN ATACAMA, CHILE

 

EARTHQUAKE SUMMARY FOR SEPTEMBER  1, 2020

 

The strongest earthquake in the world today was an M 6.5 aftershock in the Atacama region of Chile. This follows an M 6.8 and 6.3 yesterday. NEIC reported today's event was felt with maximum intensity V in Atacama at Vallenar, Copiapo and in Valparaiso and II-III in Coquimbo at La Serena, Coquimbo, Vicuna, Andacollo as well as in Villa Alemana, Valparaiso and Santiago and in San Juan, Argentina. GUC reported the aftershock of M 6.3 was felt with intensity   VI in  Atacama at Copiapo, Freirina, Huasco, Tierra Amarilla, Vallenar; V in Alto del Carmen; IV in Caldera and III in Chanaral, Diego de Almagro and in Coquimbo with V in La Serena, IV in La Higuera, Rio Hurdado, Vicuna; III in Combarbala, Monte Patria, Ovalle, Punitaqui, Chile. GUC reported the aftershock of M 4.9 was felt with intensity  III in  Atacama at Caldera, Freirina, Huasco, Vallenar and II in Alto del Carmen, Copiapo and Tierra Amarilla, Chile. Other moderate earthquakes of M 5.7, 5.7 and 5.0 occurred also were lightly felt in Atacama today. These are probably related to the full moon which arrived early on September 2 and the ongoing geomagnetic storm as discussed in the previous issue of this summary:

 

"The geomagnetic field saw active conditions today. The AP level was 26.  High latitude geomagnetic field saw storm conditions with AP 42. This is the most disturbed the field has been in nearly a year since October 25-26, 2019 when the AP level reached 29 and 25 and high latitude AP reached 62. Strong seismic enhancement is likely with this storm especially near the geomagnetic equator and at high latitudes during the next four days." (August 31, 2020)

 

and

 

"The full moon will arrive at 05:22 UT on September 2, 2020. Longitudes which are at local solar midnight at this time are near 80 West while those at solar noon are near 100 East. These include in the west, Central America and western South America and in the east Sumatra and western Indonesia and southeast Asia. These regions are likely to see moderate seismic with this full moon. Tidal triggering is not usually major at full moon but can occur  - normally near local solar midnight and noon in areas where seismicity is controlled by vertical tectonics and/or fluid motions." (September 1, 2020)

 

and

 

 

"Today's M 6.8-7.0 in Atacama, Chile is the strongest recorded within about 200 km of these epicenters since an M 6.9 on November 11, 2015. The only event with M>=6.8 in this area closer that 150 km in the past 30 years was an M 5.8 on January 30, 2013.  Forecast 126753 had expected today's activity was likely within about 150 km of the epicenters around August 28. This earthquake is located at 146 degrees from the M 6.8 in Sumatra of August 18 and at 143 degrees from the Banda Sea quake of August 21, 2020 and at the seventh node (51 degrees) from the M 7.5 in Oaxaca, Mexico of June 23, 2020 and may have been promoted by concentrated energy from those sources." (September 1, 2020)

 

O:  2SEP2020 03:04     27.9S   71.4W mb=4.9  GUC    Atacama at Caldera, Freirina,

O:  1SEP2020 21:09     28.0S   71.6W mb=6.3  GUC    Atacama at Copiapo, Freirina,

O: 01SEP2020 14:01:31  27.7S   71.5W mb=4.4  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 09:55:26  27.8S   71.5W mb=4.7  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 13:51:25  27.8S   71.6W mb=4.6  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 14:23:13  27.8S   71.6W ML=4.2  EMSC   OFFSHORE ATACAMA, CHILE

O: 02SEP2020 03:04:26  27.8S   71.5W Mw=4.7  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 10:31:51  27.9S   71.5W Mw=5.7  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 17:13:21  27.9S   71.4W Mw=5.0  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 21:09:17  27.9S   71.3W Mw=6.5  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 07:01:26  28.0S   71.2W Mw=5.7  EMSC   OFFSHORE ATACAMA, CHILE

O: 01SEP2020 20:11:59  28.0S   71.2W ML=4.0  EMSC   OFFSHORE ATACAMA, CHILE

P: 28AUG2020 126753    29.0S   70.0W 4.0-5.6 BAAAA  Coast Central Chile        

 

Moderate earthquakes continued in the high latitude ocean ridges today with  events of M 4.5 and 5.4 in the South Shetland Islands; an M 5.3 in the Pacific-Antarctic Ridge and an M 5.1 in the South Sandwich Islands. This extends the ocean ridge activity to the highest latitudes. This summary had addressed the relation between this and the current strong geomagnetic storm on August 31 as:

 

"The earthquakes in Chile followed a strong series of earthquakes, mostly near the geomagnetic equator on mid-ocean ridges." (August 31, 2020)

 

The earthquake in the South Sandwich Islands occurred near local solar midnight and was likely also promoted by tidal stresses. Forecasts 126786  had expected this event around August 31 while 126787 had expected activity in the South Shetland area was also likely around August 31.

 

O:  2SEP2020 00:21:12  56.1S   27.7W mb=5.1  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 31AUG2020 126786    55.0S   29.0W 4.0-5.7 ABAAA  So. Sandwich Islands       

 

O:  1SEP2020 23:17:12  56.2S  143.8W Mw=5.3  EMSC   PACIFIC-ANTARCTIC RIDGE      

 

The earthquake of M 5.4 in the South Shetland Islands is the strongest in the region in the past year, surpassing the beginning of the current series when an M 5.3 occurred on August 30 and an M 5.0 on August 29, 2020.

 

O: 01SEP2020 10:53:14  62.2S   58.0W mb=4.5  EMSC   SOUTH SHETLAND ISLANDS

O:  1SEP2020 10:56:20  62.3S   58.4W mb=5.4  EMSC   SOUTH SHETLAND ISLANDS       

P: 31AUG2020 126787    60.0S   44.0W 3.0-5.7 ACCAA  So. So. America            

 

The strongest earthquake in the U.S. or Canada today was an M 3.9 in the Andreanof Islands, Alaska. It was not reported felt in this remote area.

The last event in the Andreanof Islands of M>=3.9 was an M 4.2 on August 30, 2020 but the last within about 100 km of today's epicenter was an M 5.3 on July 15, 2020. Forecast 126691 had expected the Andreanof Islands would be active at the end of August or in early September.

 

O:  2SEP2020 03:00:23  51.1N  180.0W mb=3.9  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 28AUG2020 126691    51.7N  176.4W 3.5-4.9 BABAA  Andreanoff Isls, Aleutians 

 

An unusual series of light earthquakes (up to M 3.3) in the Cornwallis Island area of Nunavut, Canada occurred today. This activity is the strongest within about 150 km of this epicenter  and the only such event in the area in the past 30 years was an M 4.0 on November 26, 2012. Today's swarm is at 103-104 degrees from the M 7.0 in Atacama, Chile yesterday and was probably promoted by concentrated energy from that source. Energy from large earthquakes  reflects and refracts off internal earth boundaries and returns to around 103 degrees on the surface of the earth, often triggering unusual seismicity at that distance from the mainshock.

 

 

O:  1SEP2020 09:51:00  74.8N   96.6W ML=3.3  EMSC   CORNWALLIS ISLAND, NUNAVUT, CA

O: 01SEP2020 10:14:25  74.8N   96.6W ML=2.8  EMSC   CORNWALLIS ISLAND, NUNAVUT, CAN.

O: 01SEP2020 11:19:52  74.9N   95.5W ML=2.5  EMSC   CORNWALLIS ISLAND, NUNAVUT, CAN.

O: 01SEP2020 21:18:30  74.8N   96.6W MB=1.6  ECAN Resolute, NU    

O: 01SEP2020 20:15:03  74.8N   96.6W MB=2.2  ECAN Resolute, NU    

O: 01SEP2020 17:51:44  74.8N   96.6W MB=1.0  ECAN Resolute, NU    

O: 01SEP2020 17:50:59  74.8N   96.6W MB=1.5  ECAN Resolute, NU    

O: 01SEP2020 11:19:52  74.9N   95.5W MB=2.5  ECAN Resolute, NU    

O: 01SEP2020 10:14:25  74.8N   96.6W MB=2.8  ECAN Resolute, NU    

O: 01SEP2020 09:51:00  74.8N   96.6W MB=3.3  ECAN Resolute, NU    

 

An M 4.8 in Nicaragua today may have been triggered by tidal effects from the full moon and by atmospheric unloading associated with Tropical Storm Omar as noted in this summary:

 

"TD Omar (15E) continued today in the area off the east coast of North Carolina with winds up to 35 kts. It is expected to track to the east into the north Atlantic but not make landfall and to dissipate in the next three days. There should be little effect on local or regional seismicity with this storm." (September 1, 2020)

 

Forecast 126566 had expected today's event within about 100 km was likely at the end of August.

 

O:  2SEP2020 05:04:24  11.2N   86.8W mb=4.8  EMSC   NEAR COAST OF NICARAGUA      

P: 27AUG2020 126566    11.0N   86.0W 3.5-5.4 BAAAA  Nicaragua