SULAWESI, INDONESIA SHAKES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 22, 2021

 

The strongest earthquake in the world today was an M 5.8-5.9 in Gorontalo, Indonesia where it was felt with intensity VI according to NEIC. BMG reported this event was felt with intensity IV in Buol, III in Bone, Bolango and III in Toli-Toli, Indonesia. The last earthquake of M>=5.8 within about 200 km of this epicenter was an  M 5.9 on July 15, 2017. An M 6.1 occurred about 200 km northeast of this epicenter on January 6, 2021. Forecast 131438 had expected this earthquake was likely in the Celebes Sea within about 50 km of this epicenter around February 22.

 

O: 22FEB2021 19:22:10   1.4N  122.0E Mw=5.8  EMSC   MINAHASA, SULAWESI, INDONESIA

P: 22FEB2021 131438     1.0N  122.0E 4.0-5.6 AAAAA  Celebes Sea                

 

Several moderate earthquakes were also felt in New Zealand today. The largest of these was an M 5.2-5.7 in the Snares Island south of South Island, New Zealand.

GEONET reported this earthquake with M 5.7 was felt with moderate intensity in South Island, New Zealand by more than 339 people with weak intensity by 265; light 69; moderate 4 and extreme 1.  NEIC reported this earthquake of M 5.1 west of South Island, New Zealand was felt with intensity II-III in the area(s) of South Island, New Zealand in Southland at Riverton, Bluff and Invercargill.

An earthquake of M 5.4 also occurred in northern New Zealand in the Kermadec Islands today. The last earthquake near Snares Island with M>=5.7 was an  M 5.8 on November 24, 2018. The last of significantly larger magnitude was an M 6.1 on August 5, 2009. These are probably regional aftershocks of the M 7.8 that hit the area about 200 km to the north in South Island on July 15, 2009.  Forecast 131738 had expected today's event was likely within about 50 km around February 27.

 

O: 23FEB2021 04:07:25  47.4S  165.6E Mw=5.1  EMSC   OFF W. COAST OF S. ISLAND, N.Z

O: 23FEB2021 04:07:26  47.4S  165.7E ML=5.7  GEONET Felt with moderate intensity

P: 27FEB2021 131738    48.0S  165.0E 3.0-4.9 BAAAA  Southern S. Isl. N.Z.      

 

The strongest earthquake in the western hemisphere today was an M 5.2 south of Chiapas and Guatemala. It was reported by NEIC to have been felt with intensity VI in Puerto Madero and II in Tlalnepantla, Mexico. It is located at 103 degrees from the M 7.7 in the Loyalty Islands of February 10 and may have been promoted by energy from that source. Volcanic activity in Guatemala as described in the previous issue of this summary may also have helped trigger this earthquake:

 

 

"Three volcanoes were in eruption in Guatemala today, having begun this eruptive behavior in mid-February. These eruptions were strong and occurred at Volcan de Fuego, Pacaya and Santa Maria. These volcanoes are at 103 degrees from the M 7.7 in the Loyalty Islands of February 10 and began erupting several days after that event. They are also near that distance from the M 7.1 in Honshu, Japan of April 13. They were probably promoted into eruption by energy from the Loyalty Islands." (February 21-22, 2021)

 

Forecast 131487 had expected this activity within about 25 km was likely around February 21.

 

O: 23FEB2021 02:18:11  13.9N   93.2W ML=4.1  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 22FEB2021 17:05:35  14.3N   93.4W ML=4.1  EMSC   OFF COAST OF CHIAPAS, MEXICO

O: 22FEB2021 15:21:22  14.4N   93.1W Mw=5.2  EMSC   OFFSHORE CHIAPAS, MEXICO     

P: 21FEB2021 131487    14.0N   93.0W 3.5-5.3 AAAAA  Chiapas, Mexico            

 

The strongest earthquake in the U.S. or Canada today was an M 4.5 near Vancouver Island, B.C. Canada. NEIC reported it was lightly felt in Washington State at Oak Harbor, Kelso, and Lake Stevens. This continues a regional seismic activation which in the past several days has included an M 3.8 south of San Francisco, California and an M 5.1 off the coast of Oregon. Today's event is the strongest within about 150 km of this epicenter since an M 4.7 about 150 km to the north on December 9, 2018 and prior to that an M 4.5 about 100 km northeast of this on October 11, 2017. Forecast 131644 had expected today's activity was likely within about 50 km of today's epicenter around February 21.

 

O: 22FEB2021 13:54:29  47.8N  128.7W mb=4.5  EMSC   OFF COAST OF WASHINGTON      

P: 21FEB2021 131644    47.9N  129.1W 2.8-5.1 AAAAA  Vancouver Island area      

 

An earthquake of M 4.5 also occurred in the Fox Islands, Aleutians, Alaska today. It was not reported felt in this area. The last earthquake in the Fox Islands of M>=4.5 was an M 4.5 on January 8, 2021 about 100 km west of today's epicenter. These may be regional aftershocks of an M 6.4 in the Fox Islands of December 1, 2020. Forecast 131656 had expected today's event within about 50 km was likely around February 18.

 

O: 22FEB2021 20:03:21  52.2N  169.9W mb=4.5  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 18FEB2021 131656    52.4N  169.4W 3.5-5.1 BAAAA  Fox Islands, Aleutians     

 

RISE IN VOLCANISM CONTINUES IN GUATEMALA

 

EARTHQUAKE SUMMARY FOR FEBRUARY 21, 2021

 

Three volcanos were in eruption in Guatemala today, having begun this eruptive behavior in mid-February. These eruptions were strong and occurred at Volcan de Fuego, Pacaya and Santa Maria. These volcanoes are at 103 degrees from the M 7.7 in the Loyalty Islands of February 10 and began erupting several days after that event. They are also near that distance from the M 7.1 in Honshu, Japan of April 13. They were probably promoted into eruption by energy from the Loyalty Islands. Similar eruptions have occurred this week at Merapi, Java, Indonesia and in Etna, Sicily, Italy.

 

A moderate earthquake of M 3.8 shook a large section of Central California around San Francisco today. NEIC reported shaking with intensity II-III in Central California at Gilroy, San Martin, Morgan Hill, San Juan Bautista, Aromas, Watsonville, Hollister, San Jose, Salinas, among other communities within about 100 km of the epicenter. This follows a series of light earthquakes felt in the area over the past several days. Today's event of M 3.8 is the largest in the area south of San Francisco since an M 4.2 on January 17 and January 2, 2021 about 50 km south of this epicenter. The of larger magnitude within about 50 km of this epicenter was an M 3.9 on January 2, 2020. Forecast 131549 had expected today's event was likely within about 10 km of this epicenter around February 24. San Francisco is located at the fifth node (72 degrees) from the M 7.1 in Honshu, Japan of February 13 and had been expected, in this summary,  to see enhanced seismicity at this time. Other activity at this distance from Japan today occurred in Tonga and Fiji.  It is also at 103 degrees from the Mindanao, Philippines quake of January 21, 2021 and was probably also promoted from that source.

 

O: 22FEB2021 01:38:12  37.1N  121.5W ML=3.6  EMSC   NORTHERN CALIFORNIA          

O: 22FEB2021 01:38:13  37.0N  121.6W ML=3.8  ANSS   NORTHERN CALIFORNIA          

P: 24FEB2021 131549    37.1N  121.5W 2.5-4.9 AAAAA  Central California         

 

O: 22FEB2021 05:41:06  37.8N  122.0W Md=2.3  EMSC   SAN FRANCISCO BAY AREA, CALIF.

P: 20FEB2021 131550    37.9N  122.0W 2.5-4.6 AAAAA  Central California         

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Andreanof Islands of Alaska. This is probably an aftershock of an M 5.6 in the Andreanof Islands which occurred on February 19. Forecast 131652 expected today's event was likely around February 23 within about 100 km of this epicenter.

 

O: 21FEB2021 15:02:33  50.9N  179.3W mb=4.8  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 23FEB2021 131652    51.6N  179.6W 3.5-5.1 AAAAA  Andreanoff Isls, Aleutians 

 

The strongest earthquake in the world today was an M 5.4 aftershock in the area southeast of the Loyalty Islands. This follows the M 7.7 in this region of February 10 and is not an unusual earthquake for this time in the aftershocks sequence. Forecast 131712 had expected today's activity in the Loyalty Islands around February 21-23.

 

O: 21FEB2021 17:14:29  22.7S  172.1E mb=4.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 21FEB2021 19:36:55  22.7S  171.5E mb=4.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 21FEB2021 20:36:47  22.9S  172.2E mb=4.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 22FEB2021 05:17:36  23.0S  172.9E Mw=5.4  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 21FEB2021 22:54:34  23.3S  171.5E Mw=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

P: 21FEB2021 131712    22.0S  170.0E 4.0-5.5 ABAAA  Loyalty Islands            

P: 23FEB2021 131712    23.0S  171.0E 4.0-5.3 BAAAA  Loyalty Islands            

 

MODERATE EARTHQUAKES AT HIGH LATITUDES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 20, 2021

 

A series of moderate earthquakes occurred today at high latitudes. The largest earthquakes in the world today were of M 5.1-5.4. These occurred off the coast of Oregon (M 5.1), in Southwestern Siberia, Russia (M 5.1), the Kuril Islands (M 5.4). These may have been enhanced by effects associated with the strongest geomagnetic storm since November 23, 2020 as described in this and previous issues of this summary:

 

"The geomagnetic field saw active to stormy conditions today. The AP level was 20.  High latitude geomagnetic field  saw strong storms with AP 40. This storm continues the strongest at high latitudes since AP at high latitudes reached 45 on November 22, 2020. Strong excursions in the geomagnetic field can be accompanied by enhanced seismicity at high latitudes and near the geomagnetic equator in the next several days." (February 19-21, 2021)

 

The strongest earthquake in the U.S. or Canada today was an M 4.9-5.1 off the coast of Oregon. NEIC reported this earthquake of M 5.1 off the coast of Oregon  was felt with intensity II-III in the area(s) of Oregon at Stayton, Port Orford, Toledo and Springfield.  This is an active area, the last earthquake with M>=5.1 within about 200 km of this epicenter was an M 5.7 on December 29, 2020 and prior to that an M 5.9 on September 5, 2019. Forecast 131636 had expected this event was likely in this area around February 18. Like recent activity in the Fiji Islands and in the Loyalty Islands, this event is at the 11th node (65.5 degrees) from the Honshu earthquake of M 7.1 in Japan of February 13 and may have been promoted by energy from that source.

 

O: 20FEB2021 21:22:35  43.7N  128.0W mb=4.9  EMSC   OFF COAST OF OREGON

O: 20FEB2021 21:15:54  43.6N  127.9W Mw=5.1  EMSC   OFF COAST OF OREGON          

P: 18FEB2021 131636    44.3N  129.4W 3.0-4.4 AAAAA  Off Coast of Oregon        

 

The strongest of today's events was an M 5.4 in the Kuril Islands of northern Japan off the eastern coast of Hokkaido. This is the strongeset earthquake in the Kuril Islands within about 200 km of this epicenter in more than a year - since an M 6.6 on January 28, 2020 and prior to that an M 5.7 on May 14, 2019. Forecast 131615 had expected today's activity was likely within about 75 km around February 18. This event is at the fifth node (72 degrees) from the M 7.7 in the Loyalty Islands of February 10 and was probably promoted by energy from that source.

 

O: 20FEB2021 13:23:27  43.3N  146.9E mb=5.4  EMSC   KURIL ISLANDS                

P: 18FEB2021 131615    44.0N  147.0E 3.5-5.4 AAAAA  Hokkaido, Japan            

 

The M 5.1 in southwestern Siberia, Russia was reported felt lightly in that region today. It was followed by an M 4.6 about two minutes later. An M 6.7 hit about 300 km southeast of this epicenter on January 11, 2021 but the last event of M>=5.1 within about 250 km was an M 5.1 on June 6, 2012, an aftershock of an M 6.7 on February 26, 2012. Forecast 131339 had expected an enhanced regional event within about 150 km of today's epicenter was likely around February 17.

 

NEIC reported this earthquake of M 5.1 in Southwestern Siberia, Russia was felt with intensity II-III in the area(s) of Southwestern Siberia, Russia at Kyzyl Tyva, Shushenskye and Zelenyy Bor, Krasnojarsi, Russia. This activity is at about 100 degrees from the M 7.7 of February 10 in the Loyalty Islands and may have been promoted by energy from that event.

 

O: 21FEB2021 01:39:02  52.3N   97.3E mb=4.6  EMSC   SOUTHWESTERN SIBERIA, RUSSIA

O: 21FEB2021 01:37:10  52.3N   97.6E mb=5.1  EMSC   SOUTHWESTERN SIBERIA, RUSSIA 

P: 17FEB2021 131339    51.0N   98.0E 3.0-4.4 BBAAA  So. Siberia                

 

A moderate earthquake was felt in South Island, New Zealand today. This was an M 4.2-4.3 in the general area of Christchurch, South Island, New Zealand. GEONET reported this earthquake was felt with moderate intensity in the area of Christchurch, South Island, New Zealand. 112 felt reports were published including 78 of weak and 28 of light shaking;  7 moderate; 0 strong; 0 severe and 0 extreme shaking in northern South Island. Forecast 131736 had expected this event within about 100 km was likely around February 19.

 

O: 20FEB2021 07:33:27  42.9S  172.3E ML=4.2  EMSC   SOUTH ISLAND OF NEW ZEALAND  

O: 20FEB2021 07:33:27  42.9S  172.2E MS=4.3  GEONET Felt with moderate intensity

P: 19FEB2021 131736    43.0S  171.0E 3.0-5.0 AAAAA  So. Island, N.Z.           

 

MODERATE QUAKES SHAKE ALEUTIANS, ALASKA; UNUSUAL QUAKE IN EGYPT

 

EARTHQUAKE SUMMARY FOR FEBRUARY 19, 2021

 

The strongest earthquake in the U.S. or Canada today was an M 5.4-5.6, followed by several moderate aftershocks in the western Andreanof Islands, Aleutians, Alaska. These events were reported with moderate intensity at Adak, Alaska. This was also the largest earthquake in the world today. Recent earthquakes of M>=5 in the area included an M 5.2 on February 14, 2020 and an M 6.1 on January 3, 2021. Today's activity is probably aftershocks of the January event. Forecast 131652 had expected today's activity within about 50 km was likely around February 23.

 

O: 19FEB2021 09:08:44  50.9N  179.3W ml=3.7  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 20FEB2021 04:10:53  50.9N  179.4W ML=3.9  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 20FEB2021 04:14:11  51.0N  179.4W mb=4.5  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 19FEB2021 09:11:24  51.1N  179.3W Mw=5.6  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 19FEB2021 09:19:07  51.1N  179.2W mb=4.8  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 19FEB2021 23:03:02  51.1N  179.0W ml=3.6  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

O: 19FEB2021 09:08:44  50.9N  179.3W ml=3.7  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 23FEB2021 131652    51.6N  179.6W 3.5-5.1 BAAAA  Andreanoff Isls, Aleutians 

 

An M 3.8, possibly triggered by the M 5.6, occurred about six hour later in the central Andreanof Islands. Forecast 131323 and 131324 had expected this activity within about 25-100 km of this epicenter in mid-February.

 

O: 19FEB2021 15:33:09  51.4N  176.9W mb=3.8  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS.

P: 14FEB2021 131323    51.0N  177.1W 3.5-5.0 BAAAA  Andreanoff Isls, Aleutians 

P: 17FEB2021 131324    51.1N  175.8W 3.5-5.1 AAAAA  Andreanoff Isls, Aleutians 

 

A moderate earthquake of M 4.4 also occurred in the Rat Islands today. This  event was not reported felt in this remote area. It occurred within about 45 minutes of local solar noon and was probably enhanced by tidal stresses which maximize near this hour. Forecast 131337 had expected this activity was likely within about 50 km of this epicenter around February 17.

 

O: 19FEB2021 23:21:58  51.7N  178.3E mb=4.4  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 17FEB2021 131337    51.0N  179.0E 4.0-5.7 AAAAA  Rat Islands                

 

An unusual earthquake occurred in southwestern Egypt today with M 4.6. There have been no earthquakes located in this region of southern Egypt of M>=3.5 in the past 30 years within about 500 km of this epicenter. The last within about 750 km was an M 4.7 on June 4, 2003 but nothing in southwestern Egypt. All events of M>=3.5 were smaller and occurred about 750 km to the northeast of this epicenter. The only earthquake in southwestern Egypt in recent history (the past 100 years) of M>=4.6 was an M 5.2 on December 9, 1978. This epicenter follows a series of similar sized quakes in northern Africa over the past several weeks. It may have been promoted by strong concentrated seismic energy from the Loyalty Islands M 7.7 of February 10 which is located at 145 degrees distance. It is also at the fourth node (90 degrees) from the M 7.1 of February 13 in Honshu, Japan.

 

O: 19FEB2021 08:40:41  22.9N   28.7E ML=4.6  EMSC   EGYPT                        

 

An unusually large earthquake of M 4.2 was also widely felt today in northern Oklahoma and southern Kansas. NEIC reported this earthquake of M 4.2 in Northern Oklahoma was felt with intensity VII in the area(s) of Northern Oklahoma at Jet; V in Wakita; IV in Anthony, Nash, and in southern Kansas in Kiowa, Attica with III in Manchester, Burlington, Cherokee, Medford, Oklahoma. Two earthquakes of M>=4.2 have hit Oklahoma in the past year - both of M 4.2 on June 21, 2020 and more recently on February 5, 2021 but both of these are more than 100 km to the southeast of today's epicenter. The last earthquake of M>=4.2 within  about 75 km of today's epicenter was an M 4.4 on May 17, 2019 and prior to that an M 4.4 on June 9, 2018. Forecast 131595 had expected today's event within about 10 km was likely  around February 19, 2021. This epicenter is located at 103 degrees from the M 7.1 in the South Shetland Islands of January 21 and from the Loyalty Islands M 7.7 of February 10 and may have been promoted by energy from those sources.

 

O: 19FEB2021 13:56:57  37.0N   98.1W Mw=4.2  EMSC   OKLAHOMA                     

P: 19FEB2021 131595    37.0N   98.0W 2.0-3.9 AAAAA  Southern Plains            

 

Two moderate earthquakes were felt in New Zealand today. NEIC reported this earthquake of M 4.3 in Cook Strait, North Island, New Zealand was felt with intensity IV-V   in the area(s) of Cook Strait, North Island, New Zealand at Porirua, Wellington, Lower Hutt, Upper Hutt, Makara-Ohariu, and II-III in Kapiti, Otaki, Masterton, Picton and Palmerston North. GEONET reported an M 4.3-4.7 earthquake was felt with moderate intensity in Cook Strait and Southern North Island. 13037 people reported feeling this event; 4247 with weak intensity; 6846 with light shaking; 1769 moderate; 158 strong; 11 with severe and 6 with extreme shaking. Forecast 131736 had expected this event within about 100 km was likely around February 23.

 

O: 20FEB2021 05:15:06  41.2S  175.0E Mw=4.3  EMSC   COOK STRAIT, NEW ZEALAND     

O: 20FEB2021 05:15:06  41.1S  174.9E ML=4.7  GEONET Felt with moderate intensity

P: 23FEB2021 131736    42.0S  175.0E 3.0-5.1 BAAAA  So. Island, N.Z.           

 

 

The other event was an M 4.2-4.3 in the general area of Christchurch, South

Island, New Zealand. GEONET reported this earthquake was felt with moderate intensity in the area of Christchurch, South Island, New Zealand. 112 felt reports were published including 78 of weak and 28 of light shaking;  7 moderate; 0 strong; 0 severe and 0 extreme shaking in northern South Island.

Forecast 131736 had expected this event within about 100 km was likely around February 19.

 

O: 20FEB2021 07:33:27  42.9S  172.3E ML=4.2  EMSC   SOUTH ISLAND OF NEW ZEALAND  

O: 20FEB2021 07:33:27  42.9S  172.2E MS=4.3  GEONET Felt with moderate intensity

P: 19FEB2021 131736    43.0S  171.0E 3.0-5.0 AAAAA  So. Island, N.Z.           

 

An M 5.6 in the Vanuatu Islands also continued the series of moderate to large quakes in that area. It was preceded by an M 5.3 earlier in the day. Forecast 131707 had expected this activity within about 50 km was likely around February 20.

 

O: 20FEB2021 02:44:06  17.5S  167.7E Mw=5.6  EMSC   VANUATU                      

O: 19FEB2021 09:20:01  17.6S  167.7E Mw=5.3  EMSC   VANUATU

P: 20FEB2021 131707    17.0S  167.0E 4.0-5.5 AAAAA  Vanuatu Islands             

 

VOLCANIC ERUPTIONS IN SICILY AND INDONESIA

 

EARTHQUAKE SUMMARY FOR FEBRUARY 18, 2021

 

Strong eruptions of Mount Merapi in Indonesia and Etna in Sicily occurred today. The eruption in Merapi was accompanied by lava avalanches and residents were warned to avoid the area. Hundreds of minor earthquakes accompanied the eruption. Mount Merapi's last major eruption was in 2010 and killed more than 300 people. A major eruption in 1930 killed more than 1300. Merapi is located south of Java, Indonesia at 7.5S 110.5E. This epicenter is at 65.4 degrees (node 11) from the Loyalty Islands activity which included an M 7.7 on February 10 and was probably promoted by energy from that source. Other importance quakes at this distance today from Honshu, Japan occurred as an M 6.1 in Fiji and as continuing activity in the Loyalty Islands.

 

O: 18FEB2021 00:00:00   7.5S  110.5E ML=5.0  EMSC   Volcanic eruption at Merapi, INDONESIA             

 

The eruption in Mount Etna, Sicily, Italy today continued a major eruption of that volcano which began several days ago. Spectacular views of this eruption and the accompanying ash cloud can be view on the web. Etna is located at 38N 15E. Forecast 131563 had expected activity near Mt. Etna around February 21.

The activity at Etna is at 90 degrees (node 4) from the M 7.1 quake in Honshu, Japan of February 13 and may have been promoted by energy from that source.

 

O: 19FEB2021 00:00:00  38.7N   15.4E ML=5.0  EMSC   Volcanic eruption at SICILY, ITALY                

P: 21FEB2021 131563    38.0N   15.0E 3.0-4.6 AAAAA  Mediterranean/Sicily       

 

The strongest earthquake in the world today was an M 6.1 in the region of Fiji.

This event is likely related to strongly enhanced seismicity to the south and east in the Vanuatu and Loyalty Islands. It is located at 65.4 degrees (node 11) from the M 7.1 in Honshu, Japan of February 13 and may have been promoted by energy from that source. The activity in the Loyalty Islands is also at 65.4 degrees from Honshu, Japan. Forecast 131371 had expected today's activity was likely within about 100 km around February 17. A strong GRB was associated with the event in Fiji today as noted in this summary:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on February 18, 2021 at 13:35 UT with BAT Fluence  n/a erg/cm2 (MAGNITUDE: n/a), Associated earthquake: Fiji Islands, M 6.1 (15:30 UT), 13:35 UT Puerto Rico, Southern Alaska, Hawaii)" (February 18, 2021)

 

This earthquake is the strongest within about 200 km of today's epicenter since

an M 6.7 on June 29, 2014.

 

O: 19FEB2021 03:10:30  14.6S  177.0W mb=5.0  EMSC   FIJI REGION                  

O: 18FEB2021 15:30:51  15.0S  176.6W Mw=6.1  EMSC   FIJI REGION                  

P: 17FEB2021 131371    14.0S  177.0W 4.0-5.4 AAAAA  Samoa Islands              

 

The second strongest earthquake in the world today was an M 5.8 in the Central East Pacific Rise. It was not felt in this remote area. This is the strongest earthquake within about 300 km of this epicenter since an M 5.8 on June 23, 2011. The last, and only event in the region of larger magnitude in the past 30 years was an M 6.0 on October 30, 2008. Today's event occurred within about 15 minutes of local solar noon and may have been promoted by high tidal stresses which maximize near this hour. Forecast 131139 had expected activity in this area was likely in mid-February. This epicenter is near the 103-105 degree distance from Honshu, Japan and may have been promoted by energy from that source.

 

O: 18FEB2021 19:31:30   9.2S  108.6W Mw=5.8  EMSC   CENTRAL EAST PACIFIC RISE    

P: 14FEB2021 131139     6.0S  111.0W 4.0-5.6 BCBAA  No. East Pacific Rise      

 

An unusual M 3.9 hit the region of Somerset Island, Nunavut, Canada today. It was not reported felt in this remote area. This event is near the North Magnetic Pole and occurred near local solar noon. It is likely it was promoted by a strong geomagnetic storm at high latitudes which occurred February 17 as noted in a previous issues of this report:

 

"The geomagnetic field saw active  conditions today. The AP level was 15.  High latitude geomagnetic field  saw stormy conditions with AP 45. This storm is the strongest at high latitudes since AP at high latitudes reached 45 on November 22, 2020. Strong excursions in the geomagnetic field can be accompanied by enhanced seismicity at high latitudes and near the geomagnetic equator in the next several days." (February 16, 2021)

 

The last activity in the Somerset Island region of Canada with the last such geomagnetic storm on November 22-22, 2020. This included an M 4.9 earthquake. The area also saw an M 6.0 on January 8, 2017, the largest in the past 30 years in the region. At the time this summary noted this event as:

 

“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 was at disturbed conditions today.  The AP level was 16.  High latitude geomagnetic field had minor storms with AP at 26." (January 8, 2017)

 

O: 18FEB2021 07:07:54  73.4N   90.6W ML=3.9  EMSC   SOMERSET ISLAND, NUNAVUT, CANA

O: 18FEB2021 07:07:54  73.4N   90.6W MB=3.9  ECAN Arctic Bay, NU                 

 

The strongest earthquake in the U.S. or Canada today was an M 4.3 in southern Alaska. NEIC reported this earthquake of M 4.1-4.3 in Southern Alaska was felt with intensity II-III in the area(s) of Southern Alaska in Pedro Bay, Homer and Anchorage. This is the strongest earthquake within about 150 km of this epicenter since an M 4.5 on December 1, 2019. Forecast 131672 had expected today's event within about 25 km was likely around February 19.

 

O: 18FEB2021 13:36:11  60.0N  153.1W ML=4.3  EMSC   SOUTHERN ALASKA              

P: 19FEB2021 131672    60.0N  153.5W 3.2-5.1 AAAAA  Central Alaska             

 

STRONG QUAKES CONTINUE IN LOYALTY AND VANUATU ISLANDS

 

EARTHQUAKE SUMMARY FOR FEBRUARY 17, 2021

 

Strong earthquakes continued throughout much of southern Vanuatu and in the Loyalty Islands today. The strongest of these occurred at a fresh epicenter as an M 6.2 south of Vila Shefa, Vanuatu where it was felt with intensity III. An earthquake of M 5.7 also occurred about 150 km north of this in the aftershock zone near Vila Shefa. The Loyalty Islands aftershock zone was also active with a strong M 6.1 aftershock. This activity near the geomagnetic equator may have been promoted by a strong geomagnetic storm which occurred yesterday as noted in this summary:

 

"The geomagnetic field saw active  conditions today. The AP level was 15.  High latitude geomagnetic field  saw stormy conditions with AP 45. This storm is the strongest at high latitudes since AP at high latitudes reached 45 on November 22, 2020. Strong excursions in the geomagnetic field can be accompanied by enhanced seismicity at high latitudes and near the geomagnetic equator in the next several days." (February 16, 2021)

 

Forecast 131707 had expected today's activity was likely within about 100 km around February 18.

 

O: 18FEB2021 06:37:31  18.9S  168.0E Mw=6.2  EMSC   VANUATU                      

P: 18FEB2021 131707    18.0S  168.0E 4.0-5.3 AAAAA  Vanuatu Islands            

 

O: 18FEB2021 00:37:02  22.9S  172.4E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 17FEB2021 22:49:39  23.2S  171.9E Mw=6.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 17FEB2021 10:51:10  23.3S  171.9E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 17FEB2021 23:35:21  23.4S  171.8E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 17FEB2021 12:59:36  22.8S  172.5E Mw=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 14FEB2021 131386    23.0S  171.0E 4.0-5.4 BAAAA  Loyalty Islands            

 

The M 5.7 aftershock in Central Vanuatu was reported by NEIC to have been felt with intensity VI in Vila Shefa, Vanuatu. It was accompanied by a series of moderate earthquakes which were also felt in Vila Shefa, Vanuatu. Forecast 131707 had expected today's activity was likely within about 100 km around February 18.

 

O: 17FEB2021 11:31:59  17.5S  167.9E Mw=5.2  EMSC   VANUATU

O: 17FEB2021 11:45:17  17.5S  167.8E mb=4.9  EMSC   VANUATU

O: 17FEB2021 12:21:44  17.5S  167.7E Mw=5.5  EMSC   VANUATU

O: 17FEB2021 15:25:15  17.5S  167.6E mb=4.7  EMSC   VANUATU

O: 17FEB2021 09:30:35  17.5S  167.8E Mw=5.4  EMSC   VANUATU                      

P: 20FEB2021 131707    17.0S  167.0E 4.0-5.5 BAAAA  Vanuatu Islands            

 

To the south of the Loyalty Islands a set of moderate earthquakes has been occurring in the Norfolk Islands, Australia. These included events of M 3.7, 3.9 with the largest to date of M 4.0 today. These had been previously noted in this summary as:

 

"An unusual earthquake of M 3.9 occurred northeast of Australia in the Norfolk Island area. The remnants of Tropical Cyclone Lucas passed over this area several days ago after triggering a series of events north of this in the Loyalty Islands which has continuing moderate aftershocks still." (February 8, 2021)

 

This activity is located near the fifth node (72 degrees) from the M 7.1 in Honshu Japan of February 13. That event, in turn was located at the 11th node (65.4 degrees) from the series in the Loyalty Islands. Other areas at this distance from Japan include Samoa and Tonga where enhanced seismicity is likely at this time.

 

O: 17FEB2021 11:34:17  27.4S  170.5E ML=4.1  EMSC   NORFOLK ISLAND, AUSTRALIA REGI

P: 14FEB2021 131386    23.0S  171.0E 4.0-5.4 BCAAA  Loyalty Islands            

 

An unusual, moderate earthquake also occurred today in the western Sahara in Morocco with M 3.6-4.5. This event is near the antipode of the Loyalty Islands (180 degrees) and was probably enhanced by energy from that source where an M 7.7 occurred on February 10. The last earthquakes in this area of Morocco within about 300 km with M>=3.6 occurred as an M 3.8 on December 29, 2018; an M 4.4 on February 20, 2017 and an M 4.0 on January 29, 2015.

 

O: 18FEB2021 02:21:26  30.2N    9.8W ML=3.6  EMSC   MOROCCO                      

 

A moderate earthquake of M 5.4 also occurred today in southern Iran. NEIC reported it was felt with maximum intensity VI in Iran at Samiram, Esfahan, Shiraz, Fars and Ahwaz, Khuzestan. This is the strongest earthquake within about 200 km of this epicenter in southern Iran since an M 5.4 on January 5, 2011. The largest regional quake in the past 30 years was an M 6.2 on May 6, 1999.  Forecast 131591 had expected this activity within this area was like around February 21. Like smaller events in California, Norfolk Island and Mt. Rainier, Washington, this activity is located at the fifth node (72 degrees) from the M 7.1 in Honshu, Japan of February 13 and may have been promoted by energy from that source.

 

O: 17FEB2021 18:35:35  30.9N   51.5E Mw=5.4  EMSC   SOUTHERN IRAN                

P: 21FEB2021 131591    30.0N   51.0E 3.8-5.4 BAAAA  So. Iran                   

 

An unusual earthquake of M 2.5 was preceded by an M 2.0 foreshock in the Mount Rainier region of Washington State today. The only other event in the Mount Rainier area in the past year with M>=2.5 was an M 2.5 on August 16, 2020. Today's  activity follows activity in the Mount St. Helens area of Washington on February 7, 2021 and may indicate the area is becoming more volcanic at this time. When the Mt. St. Helens activity occurred this summary noted:

 

 

"An M 2.6-2.8 earthquake occurred today in the Mt. St. Helens area of Washington State. NEIC reported this earthquake of M 2.8 in Washington State was felt with intensity II-III in the area(s) of Washington State at Yacolt and Carnation.  The last earthquake in the Mt. St. Helens area of M>=2 was an M 2.4 on August 26, 2020. But the last earthquake in the area of M>=2.6 occurred nearly three years ago on May 28, 2018 with M 3.0. The last of significantly larger magnitude was an M 3.9 on January 3, 2018. Forecast 131013 had expected the area would\ seen enhanced seismicity around February 9. This epicenter is at the third node (120 degrees) from the South Shetland Islands M 7.1 of January 23, 2021 and at 101 degrees from the Mindanao quake of M 7.0 of January 21 and my have been enhanced by energy from those sources." (February 8, 2021)

 

Forecast 131316 had expected today's activity in the Mount Ranier area was likely in mid-February.

 

O: 18FEB2021 00:19:43  46.9N  121.8W Ml=2.0  EMSC   MOUNT RAINIER AREA, WASHINGTON

O: 18FEB2021 03:13:52  46.9N  121.8W Ml=2.5  EMSC   MOUNT RAINIER AREA, WASHINGTON

P: 12FEB2021 131316    46.9N  122.0W 2.0-4.2 CAAAA  Washington state, U.S.     

 

MODERATELY STRONG QUAKE SHAKES GREECE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 16, 2021

 

The strongest earthquake in the world today was an M 5.1-5.5 in northern Greece. NEIC reported it was felt with intensity VII in Ahaia, Kamarai, Greece; V in Rododafni; IV in Diakopton, Mesolongion, and III in Patrai, Royitika and Lama. Greece. NEIC reported an aftershocks of M 4.5 in Ahaia, Greece was felt with intensity II-III in the area(s) of Ahaia, Greece in Rododafni (V) and Diakopton.

The last earthquake of M>=5.5 within about 200 km of this epicenter was an M 5.7 on March 21, 2020 and prior to that an M 5.4 on February 5, 2019. A strong quake  about 200 km southwest of today's epicenter occurred on October 25, 2018. Today's event may have been triggered by effects from a strong geomagnetic storm at high latitudes occurred today with the following parameters:

 

"The geomagnetic field saw active  conditions today. The AP level was 15.  High latitude geomagnetic field  saw stormy conditions with AP 45. This storm is the strongest at high latitudes since AP at high latitudes reached 45 on November 22, 2020. Strong excursions in the geomagnetic field can be accompanied by enhanced seismicity at high latitudes and near the geomagnetic equator in the next several days." (February 16, 2021)

 

Forecast 131235 had expected today's event within about 150 km was likely around  February 17 in Greece.

 

O: 17FEB2021 04:38:50  38.4N   22.0E ML=4.0  EMSC   GREECE

O: 17FEB2021 03:36:05  38.4N   22.0E mb=5.1  EMSC   GREECE                        

O: 17FEB2021 03:36:05  38.4N   22.0E mb=5.5  ANSS   GREECE                       

P: 17FEB2021 131235    39.0N   20.0E 3.0-4.8 AABAA  No. Greece                 

 

An earthquake of M 5.4 also occurred today in the area of the north coast of Papua, Indonesia. The last earthquakes within about 200 km of this epicenter with M>=5.4 occurred on March 26, 2020 and an M 6.0 on January 18, 2020. Strong earthquakes in this are can help promoted seismicity in Southern California at 103 degrees distance. Forecast 131154 had expected today's event within about 100 km was likely around February 17.

 

O: 16FEB2021 19:09:38   2.9S  139.2E Mw=5.4  EMSC   NEAR N COAST OF PAPUA, INDONES

P: 17FEB2021 131154     2.0S  139.0E 4.0-5.6 AAAAA  West Irian, PNG            

 

The strongest earthquake in the U.S. or Canada today was an M 4.0 in the Vancouver, British Columbia area of Canada. The last earthquake of M>=4 within about 100 km of this epicenter was an M 5.4 on July 22, 2020 and an M 4.7 on May 10, 2020.  Forecast 131315 had expected today's event within about 100 km was likely around February 13.

 

O: 16FEB2021 23:28:36  48.1N  130.6W MB=4.0  ECAN of Port Alice, BC              

P: 13FEB2021 131315    47.9N  129.1W 2.8-5.2 BAAAA  Vancouver Island area      

 

Moderate aftershocks were absent in the areas of Eastern Honshu, Japan and the Loyalty Islands today. Activity in central Vanuatu was also reduced. This is odd behavior for aftershock sequences and enhanced seismicity in these areas is expected to resume in the next several days. Forecast 131242 expects more seismicity in Japan in the next several days.

 

O: 16FEB2021 13:59:32  37.9N  140.8E mb=4.3  EMSC   EASTERN HONSHU, JAPAN        

P: 14FEB2021 131242    38.0N  142.0E 4.0-5.5 AAAAA  Off East Coast Honshu      

 

O: 16FEB2021 22:07:24  38.4N  141.8E mb=4.6  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 14FEB2021 131242    38.0N  142.0E 4.0-5.5 AAAAA  Off East Coast Honshu      

 

Forecast 131707 had expected the activity in Vanuatu to continue through at least February 18.

 

O: 16FEB2021 16:16:03  17.7S  167.4E mb=4.9  EMSC   VANUATU

O: 17FEB2021 03:58:38  17.7S  167.6E mb=5.0  EMSC   VANUATU

O: 16FEB2021 16:12:16  17.7S  167.5E mb=5.0  EMSC   VANUATU                      

P: 18FEB2021 131707    18.0S  168.0E 4.0-5.3 AAAAA  Vanuatu Islands            

 

STRONG EARTHQUAKES SHAKE CENTRAL VANUATU

 

EARTHQUAKE SUMMARY FOR FEBRUARY 15, 2021

 

A series of strong earthquakes hit the area of central Vanuatu today. These events of  M 5.4, 5.7 and 6.2 are located about 600 km northwest of the M 7.7 in the Loyalty Islands of February 10. These events were felt with intensity IV in Vila Shefa, Vanuatu according to NEIC. A foreshock of M 5.1 was also felt with intensity III in Vila Shefa. The strongest of today's quakes  - the M 6.2 occurred near the sub-solar point on the earth at the time of this event. The sub-solar point is the point on the earth which at which the sun is directly overhead at local solar noon. It is at this point in space and time where tidal stresses are maximized. The M 6.2 occurred within about 5 minutes of local solar noon.

 

A foreshock of M 5.3 occurred yesterday at the same epicenter. This summary noted this event because it is exactly at the sixth node (60.0 degrees) from  the M 7.1 in Honshu, Japan of February 13. It had been noted in the previous issue of this summary as:

 

"An interesting M 5.3 also occurred north of the Loyalty Islands today in the area of central Vanuatu. This is in a volcanic area and may reflect volcanism beginning after the strong regional activity in the the Loyalty Islands.  This event is located at 60.0 degrees (node 6) from the M 7.1 in Honshu, Japan of  February 13 and was probably triggered by energy from that source.  The area often sees a series of events when a moderate quake occurs. Watch for additional and perhaps larger events in this region of Vanuatu in coming days.

 

This epicenter is near the Northeast Shepherd Islands, Kuwae and Epi Volcanoes in Vanuatu and may have been associated with regional volcanism in this area of Pele Volcano, of central Vanuatu. It is near Port Vila, a major city in Vanuatu. (February 14-15, 2021) 

                                     

The last earthquake of M>=6.2 within about 150 km of today's activity occurred in Vanuatu on  January 23, 2016 with M 6.8.  Forecasts 131076 and 131380 had expected this activity was likely within about  100 km between February 7 and 17. The last earthquake within this area of M>=5.3 Today's activity occurred at the sixth node (60 degrees) from the M 7.1 in Honshu, Japan of February 13 and was probably promoted by energy from that source.

 

O: 15FEB2021 10:34:22  17.7S  167.8E mb=4.9  EMSC   VANUATU

O: 15FEB2021 20:04:47  17.7S  167.9E mb=5.1  EMSC   VANUATU

O: 16FEB2021 00:49:25  17.7S  167.6E Mw=6.2  EMSC   VANUATU

O: 16FEB2021 01:31:59  17.7S  167.8E Mw=5.7  EMSC   VANUATU

O: 15FEB2021 16:51:30  17.8S  167.6E mb=4.9  EMSC   VANUATU

O: 16FEB2021 03:37:10  17.9S  167.7E Mw=5.3  EMSC   VANUATU

O: 16FEB2021 04:44:17  17.9S  167.8E mb=5.0  EMSC   VANUATU

O: 16FEB2021 01:22:19  17.6S  167.8E mb=5.4  EMSC   VANUATU                      

P:  7FEB2021 131076    17.0S  167.0E 4.0-5.4 CAAAA  Vanuatu Islands            

P: 17FEB2021 131380    16.0S  168.0E 4.0-5.6 ABAAA  Vanuatu Islands            

 

Aftershocks of M 5.3 occurred in the region off the east coast of Honshu, Japan today. These were reported by NEIC to be felt with intensity II-III in Fukushima and Miyagi, Japan. Forecast 131242 had expected this activity within about 50 km was likely around February 14.

 

O: 16FEB2021 00:48:30  37.6N  141.6E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 15FEB2021 11:27:19  37.7N  141.8E mb=4.2  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 15FEB2021 11:59:50  37.7N  141.6E mb=4.4  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 15FEB2021 12:26:05  37.6N  141.5E Mw=5.3  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 14FEB2021 131242    38.0N  142.0E 4.0-5.5 AAAAA  Off East Coast Honshu      

 

Aftershocks also continued today in the Loyalty Islands south of Vanuatu. These follow the M 7.7 in the Loyalty Islands of February 10. Forecast 131386 had expected this activity was likely around February 14.

 

O: 15FEB2021 10:07:02  22.9S  172.6E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 15FEB2021 21:21:05  23.2S  171.3E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 15FEB2021 21:26:49  23.2S  171.6E mb=5.4  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 15FEB2021 14:06:44  22.7S  172.1E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 14FEB2021 131386    22.0S  172.0E 4.0-5.3 AAAAA  Loyalty Islands            

P: 14FEB2021 131386    23.0S  171.0E 4.0-5.4 AAAAA  Loyalty Islands            

 

The most active area of the U.S. or Canada today occurred near the North Geomagnetic Pole in the Pond Inlet, Nunavit area of Canada. The largest in a swarm of four minor events in this area today occurred with M 3.3 and 3.0 within five minutes of local solar midnight and were probably promoted by tidal stresses which maximize near this hour of the day. The last events of M>=3.3 in this area were an M 4.6 on October 22, 2019 and February 12, 2015.  Forecast 131360 had expected activity within about 100 km of these epicenters between February 13 and 16. This activity is at the third node (120 degrees) from the Loyalty Islands and may have been promoted by energy from that area.

 

O: 15FEB2021 05:52:55  72.3N   75.8W MB=2.9  ECAN Pond Inlet, NU   

O: 15FEB2021 04:59:53  72.2N   75.8W MB=3.0  ECAN Pond Inlet, NU   

O: 15FEB2021 04:58:41  72.2N   75.8W MB=3.3  ECAN Pond Inlet, NU   

O: 14FEB2021 13:40:46  72.3N   75.7W MB=2.4  ECAN Pond Inlet, NU                 

P: 13FEB2021 131360    73.3N   73.5W 2.5-3.9 AAAAA  Baffin/Davis Strait Canada 

P: 16FEB2021 131360    71.0N   75.0W 2.5-4.1 AAAAA  Baffin/Davis Strait Canada 

 

 

THEY'RE BACK!!

 

EARTHQUAKE SUMMARY FOR FEBRUARY 14, 2021

 

After a day of extreme quiet in the Loyalty Islands, seismicity returned to the

area with an M 5.8 aftershock and several associated moderate quakes in the area

of M 5.0-5.5. These are aftershock of the M 7.7 in Vanuatu of February 11 and were not reported felt in this remote area. This lull in activity had been noted

in the previous issue of this summary as:

 

"In a surprising development the M 7.1 in Japan appears to have stopped the aftershock sequence of the M 7.7 in the Loyalty Islands. There were no moderate aftershocks located in that region today. The area may have locked up with additional energy from Japan but this is not certain." (February 14, 2021)

 

An interesting M 5.3 also occurred north of the Loyalty Islands today in the area of central Vanuatu. This is in a volcanic area and may reflect volcanism beginning after the strong regional activity in the Loyalty Islands.  This event is located at 60.0 degrees (node 6) from the M 7.1 in Honshu, Japan of February 13 and was probably triggered by energy from that source.  The area often sees a series of events when a moderate quake occurs. Watch for additional and perhaps larger events in this region of Vanuatu in coming days.

 

This epicenter is near the Northeast Shepherd Islands, Kuwae and Epi Volcanoes in Vanuatu and may have been associated with regional volcanism in this area of Pele Volcano, of central Vanuatu. It is near Port Vila, a major city in Vanuatu.

 

Forecasts 131076 and 131380 had expected this activity was likely within about  100 km between February 7 and 17. The last earthquake within this area of M>=5.3 was an M 6.2 and aftershocks beginning on September 6, 2020 about 75 km north of today's epicenter. An M 5.8 hit near this epicenter on Marcy 28, 2020. 

 

NEIC reported this earthquake of M 5.3 in Vanuatu was felt with intensity IV in the area(s) of Vanuatu at Vila Shefa.

 

O: 14FEB2021 19:43:00  17.6S  168.0E Mw=5.3  EMSC   VANUATU                      

P:  7FEB2021 131076    17.0S  167.0E 4.0-5.4 CAAAA  Vanuatu Islands            

P: 17FEB2021 131380    16.0S  168.0E 4.0-5.6 BBAAA  Vanuatu Islands            

 

The aftershocks in the Loyalty Islands today followed a one-day lull in activity

in the area following the M 7.1 in Japan. Today's activity was not reported felt but included events of M 5.8, 5.3, 5.1 among others. Forecast  131386 had expected today's activity was likely within about 50 km of these events around February 14.

 

O: 14FEB2021 08:45:03  22.6S  171.2E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 13:22:42  23.1S  171.6E mb=4.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 16:06:28  23.2S  171.3E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 12:16:49  23.3S  171.5E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 13:52:28  23.3S  171.6E mb=4.8  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 15:01:42  23.3S  171.7E Mw=5.8  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 15:07:38  23.4S  171.7E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 14FEB2021 08:09:30  22.5S  171.2E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

O: 14FEB2021 08:09:30  22.5S  171.2E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 14FEB2021 131386    22.0S  172.0E 4.0-5.3 AAAAA  Loyalty Islands             

 

The aftershock sequence off the east coast of Honshu, Japan continued today  with the largest even an M 5.2. These follow the M 7.1 which occurred in this area on February 13 and had been expected in forecast 131242 to occur within about 50 km around February 14.

 

NEIC reported this earthquake of M 4.6 in Honshu, Japan was felt with intensity II-III in the area(s) of Honshu, Japan in Miyagi. An M 5.1 was felt with intensity VI in Fukushima and II-III in Miyagi and Chiba, Japan.

 

O: 14FEB2021 21:25:30  37.5N  141.5E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 08:48:30  37.6N  141.6E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 09:26:58  37.6N  141.8E mb=4.6  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 11:41:30  37.6N  141.7E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 14:20:30  37.6N  141.7E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 07:59:23  37.7N  141.6E mb=4.5  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 10:41:30  37.7N  141.7E ML=4.2  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 07:31:50  37.5N  141.5E mb=5.2  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 14FEB2021 131242    38.0N  142.0E 4.0-5.5 AAAAA  Off East Coast Honshu      

 

The largest earthquake in the U.S. or Canada today was an M 5.2 in the western Andreanof Islands, Aleutians, Alaska. It may have been felt in Adak. The only earthquakes in the past year in the western Andreanof Islands with M>5.2 occurred on January 3, 2021 (M 6.1) and March 2, 2020 (M 5.7). The last of M 5.2 was an M 5.2 on June 19, 2020. Forecast 131323 had expected today's activity within about 50 km was likely around February 13.

 

O: 14FEB2021 19:13:18  51.4N  179.3W mb=5.2  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 13FEB2021 131323    50.9N  179.0W 3.5-5.0 AAAAA  Andreanoff Isls, Aleutians 

 

 

MAJOR EARTHQUAKE SHAKES EASTERN HONSHU, JAPAN

 

EARTHQUAKE SUMMARY FOR FEBRUARY 13, 2021

 

JMA reported this earthquake of M 7.1 was felt with Japanese Intensity VI+ in Miyagi and Fukushima; V+ in Tochigi, V- in Iwate, Yamagata, Ibaraki and Saitama; and IV in Aomori, Akita, Gumma, Chiba, Tokyo, Niigata, Yamanashi and Shizuoka and III in Ishikari, Oshima, Sorachi, Iburi, Hidaka, Kushiro, Akita, Nagano.

NEIC reported intensity IX with damage in Soma, Fukushima, Watan, Miyagi and Shiroshi, Miyagi with VIII in Shibata, Miyagi. Intensity VI was reported from Miyagi at Ishinomaki, Kakuda, Natori, Tagajo, Sendai with VI in Iwaki, Fukushima among others. The government reported that more than 100 people were injured in today's earthquake but no one was killed. Rockfalls were common and covered many roads including a main artery through Fukushima. The power plant there has been out of operation since the quake of March 11, 2011. Most train services were suspended and some damage occurred to rail structures. Many areas of Honshu lost power during the quake. This included near a million customers. A tsunami warning was issued by JMA but only small waves were seen. The last earthquake within about 200 km of today's epicenter with M>=7.1 was an M 7.3 on December 7, 2012. The only other such event in the region since the mainshock of M 9.1 on March 11, 2011 was an M 7.0-7.1 on April 7, 2011. The event on March 11, 2011 was preceded by an M 7.5 foreshock on March 9, 2011. This was closely associated with a major solar flare and is not likely to be repeated under the current geophysical conditions.

 

The mainshock in Honshu, Japan was followed about an hour later by an M 6.0 in New Guinea. This epicenter is at 45.0 degrees from Japan (node 8) and was probably triggered by energy from the Japanese source. In a surprising development the M 7.1 in Japan appears to have stopped the aftershock sequence of the M 7.7 in the Loyalty Islands. There were no moderate aftershocks located in that region today. The  area may have locked up with additional energy from Japan but this is not certain.

 

Far-field triggering is possible from the M 7.1 in Japan today. Areas at 144 degrees include the South Shetland Islands, northern Chile and southern Peru; near 103 degrees in central and western Mexico, the Madeira Islands, southern Spain, Madagascar, Mayotte, at 120 degrees (node 3) at Panama and Costa Rica and Puerto Rico; at 90 degrees (node 4) at Oklahoma and Texas, South Island, New Zealand; at 72 degrees (node 5) in Central and northern California, Iceland, Croatia, eastern Europe and Turkey, Fiji, Tonga, Loyalty Islands; in  western Indonesia at 60 degrees (node 6); in Tajikistan, Indonesia, Philippines  at node 7 (51 degrees) and in New Britain, Xizang, Alaska Peninsula at node 8 (45 degrees).

 

Today's event followed closely after a strong GRB earlier in the day which occurred near local solar noon. The preliminary parameters of that GRB (see below) are:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on February 12, 2021 at 04:25 UT with BAT Fluence  8.0e10-7 erg/cm2 (MAGNITUDE: >19.0), Associated earthquake: Honshu, Japan, 7.1, Cook Strait, NZ M 4.9; Central Turkey M 4.7)" (February 13, 2021)

 

A more immediate trigger for today's earthquake, however is a geomagnetic storm which peaked with KP 6 at high latitudes at 14:00 UT shortly before the  occurrence of the M 7.1 in Japan. This is the fourth largest such storm of since November 22, 2020 with similar occurrences at middle latitudes on February 2-3, February 7 and January 25, 2021. Each of these was accompanied by moderate quakes in Japan or Taiwan. Of particular note was an M 4.2 foreshock on February 3 which occurred in the Fukushima area at the peak of that geomagnetic storm. But note that the last significantly larger geomagnetic storm and the last moderately strong precursory activity off the coast of eastern Honshu, Japan both occurred on November 22, 2020.  This had been noted at the time in this summary:

 

"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. ...  Today's event ... 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." (November 22-23, 2020)

 

Parameters of today's storm are:

 

The geomagnetic field saw active conditions today. The AP level was 13.  High latitude geomagnetic field also saw minor storm conditions with AP 18. Moderate geomagnetic storms such as this can help promote seismicity at high latitudes and near the geomagnetic equator such as the M 7.1 in Japan and the following M 6.0 in New Guinea today.

 

Forecasts 131242 and 131261 had expected enhanced seismicity within about 50 km  of these epicenter near the coast of Honshu was likely around February 14.

 

O: 13FEB2021 14:23:30  37.6N  141.7E ML=4.3  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 14:36:42  37.6N  141.8E mb=4.9  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 14:58:30  37.6N  141.8E ML=4.4  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 15:36:30  37.6N  141.5E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 16:53:30  37.6N  141.6E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 21:08:30  37.6N  141.6E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 14:07:52  37.7N  141.6E Mw=7.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 14:55:30  37.7N  141.7E ML=4.3  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 15:05:30  37.7N  141.7E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 15:15:30  37.7N  141.6E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 16:32:59  37.7N  141.8E mb=4.4  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 17:01:30  37.7N  141.6E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 17:36:30  37.7N  141.8E ML=4.0  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 05:53:54  37.7N  141.7E mb=4.3  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 14:51:43  37.8N  141.6E mb=5.3  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 13FEB2021 16:14:41  37.8N  141.7E mb=4.3  EMSC   NEAR EAST COAST OF HONSHU, JAPAN

O: 14FEB2021 05:11:21  37.5N  142.0E mb=4.6  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 14FEB2021 131242    38.0N  142.0E 4.0-5.5 AAAAA  Off East Coast Honshu      

P: 14FEB2021 131261    38.0N  143.0E 4.0-5.5 AAAAA  So. of Honshu              

 

 

A regional aftershock of M 5.2 off northern Honshu, Japan was felt with intensity II-IV in Kanagawa, Saitama, Aomori and Iwate, Japan. If a strong shock follows today's M 7.1 this is a likely location for it to initiate. This is the largest earthquake within about 100 km of this epicenter since an M 6.1 on September 12, 2020. Today's event is probably a regional aftershock of the M 7.7 about 200 km to the southwest.   Forecast 131282 had expected this event within this area was likely around February 12.

 

O: 13FEB2021 18:25:29  39.2N  142.4E mb=5.2  EMSC   NEAR EAST COAST OF HONSHU, JAP

P: 12FEB2021 131282    40.0N  142.0E 3.5-5.7 AAAAA  Hokkaido, Japan            

 

The mainshock in Honshu, Japan is at the seventh node (51.4 degrees) from the

M 6.3 in Tajikistan yesterday and was probably promoted by energy from that source.

 

 

Since it has only been 10 years since the activity of March, 2011 in the same rupture zone, hardly enough time for the accumulation of great regional stress after those events, a second major earthquake seems unlikely to follow in the next several days. Still, the parallels with today's event and the M 7.1 foreshock on March 9, 2011 could suggest a repeat of that process at lower magnitudes. So it may be instructive to revisit what this summary reported on March 9, 2011 the day of the M 7.1 foreshock and prior to the mainshock in the Fukushima area of Japan. This is from the summary of March 9, 2011:

 

"The mainshock of this earthquake off Honshu is at 51.4 degrees from the last strong earthquake in the world - the M 6.6 in the Solomon Islands on March 6.

This is exactly at the seventh node (360/7=51.4 degrees) from that event. Seismic promotion from this earthquake of the Honshu event is very likely.

 

As noted at the time of the last moderate earthquakes in this region of Japan, seismic activity in this region is often triggered by unusually strong solar flares. On February 15 and X2.2 flare was followed by events of M 5.4 and 5.7 at the same epicenter as today's earthquake, events which were foreshocks to those of today. At the time we noted:

 

"A pair of moderate earthquakes also occurred north of Indonesia in the area off the east coast of Honshu, Japan today with M 5.4, 5.7. These earthquake were well offshore and were not reported felt on the Japanese mainland. This epicenter was also subsolar during the great X2.2 flare today. Japan often shows strong triggering with major flares on the sun. The timing places the earthquake occurring four minutes after flare 7180, a C1.7 flare." (February 15, 2011)

 

As with the foreshocks of February 15, the mainshock today occurred about 15 minutes after local solar noon (sub-solar). At exactly local solar noon the largest solar flare of the day, a C6.4 class solar flare occurred which may have been the immediate trigger for this earthquake. The largest flare since the X2.2 on February 15 occurred several hours earlier on March 8 as an M3.7 flare (#1830). The sun has been at its most active state since February 15 with at least six M-class solar flares in the past two days. This data is located in our GEOMAGNETIC section below.

 

The earthquake also follows the strongest volcanic eruption in Japan in the past seven years. This was considered a possible precursor to such an event in eastern Honshu in our report of February 6, 2011 as stated:

 

"The eruption of Kirishima Volcano in Japan continued today. Nearly 100 million tons of ash have fallen from the eruption which began on January 26 and nine large explosions have occurred at Shinmoedake. The lava dome which has formed in this eruption in southwestern Japan is now 110 meters high and 600 meters in diameter. This is the largest eruption of a volcano in Japan since December 2004 when Miyakejima volcano erupted to the south of Tokyo. This eruption was largely considered a precursor to the upcoming Tokyo great earthquake." (February 6, 2011)

 

The first and strongest aftershock occurred 12 minutes after the mainshock. This is very common in large events and is statistically significant. It is also the time of the first arrival of a seismic wave back to the epicenter - the PcS phase which is a reflection off the core-mantle boundary back to the epicentral region. The highly unstable condition of the seismic regime  after the mainshock makes the region particularly vulnerable at this time to dynamic triggering from such returning seismic waves. The next major phase to return to the epicentral area is the SS-phase which arrives 47 minutes after the mainshock. An M 5.2 aftershock coincides with this return phase at 04:32 UT another possible of a triggered aftershock.

 

Followers of internet news, newspapers and TV often see the statement "large earthquakes are common in Japan. 20% of the world's earthquakes of magnitude 6 or greater occur in the region of Japan". This is a statement which comes from some central clearing house and is very misleading. Most Americans think of  Japan as the Island of Honshu and perhaps Hokkaido. But Japan actually extends from about as far north as the northern Kuril Islands at the same latitude as much of southern Alaska to the southern Ryukyu Islands, as far south as much of Mexico and Cuba and from east to west from the Asian coast to the Volcano Islands. This is a region as large as the United States east of the Rocky Mountains. But the statistics over the past 20 years do not  bear this out either. Since 1990 NEIC has reported 3293 earthquakes of M>=6 in the world. Of these 318 have been located in this region of greater Japan, only 10% of the global earthquakes of M>=6, half the number claimed. In the past 10 years this is even a smaller percentage, at 155 out of 1740 such  events - about 9% and in the past five years this has fallen to about 8% of the global seismicity at this magnitude level. This percentage is much lower if only the populated Islands of Honshu, Hokkaido and Kyushu area are included, this falls to 121 of 3293 events of M>=6 since 1990 or about 3-4% of the earthquakes in the world, a far cry from the purported 20%.

 

The earthquake today is the strongest in the region of greater Japan in the past three years. The only events of M>=7.4 in the area in the past five years occurred in the Kuril Islands on January 13, 2007 and January 15, 2009 with M 8.1 and 7.4 respectively. The only earthquake of larger magnitude within 300 km of today's earthquake in the past 20 years was an M 7.9 on December 28, 1994. The only such earthquake near the Island of Honshu of M>=7.4  in the past 20 years was an M 7.4 in southern Honshu on September 5, 2004. This should put the earthquake today in perspective." (March 9, 2011)

 

The strong M 6.0 quake in New Guinea today at 45.0 degrees (node 8) from the M 7.1 in Japan was reported by NEIC to have been felt with intensity II in Port Moresby, Papua New Guinea. This is the strongest earthquake within about 200 km of this epicenter since an M 6.0 on October 1, 2020 and an M 6.0 on March 19, 2018. The last in this region of M>6.0 was an M 6.9 on October 17, 2016.  Forecast 131137 had expected this event within this area was likely around February 11.

 

O: 13FEB2021 15:33:51   7.2S  149.5E Mw=6.0  EMSC   NEW BRITAIN REGION, P.N.G.   

P: 11FEB2021 131137     6.0S  150.0E 4.0-5.4 ABAAA  New Ireland                

 

The strongest earthquake in the U.S. or Canada today was an M 5.2-5.3 in the Kodiak Alaska region where it was reported by NEIC to have been felt with intensity II-III at Kodiak and in Homer and Anchorage. This is the strongest earthquake within about 150 km of this epicenter since an M 5.3 on May 11, 2018. An M 6.8 on May 29, 2015 was the last event of larger magnitude in this region of the Alaska Peninsula. Like the M 6.0 in New Guinea, this is located at the eighth node (45 degrees) from the M 7.1 in Japan today. This epicenter is at 142 degrees from the South Shetland Islands M 7.1 of January 23 and may have been enhanced by energy from that source.

 

O: 13FEB2021 13:20:02  57.1N  155.1W ml=3.4  EMSC   ALASKA PENINSULA             

O: 13FEB2021 13:08:54  57.2N  155.2W Mw=5.3  EMSC   ALASKA PENINSULA

O: 13FEB2021 13:08:55  57.1N  155.0W Mw=5.3  ANSS   ALASKA PENINSULA

P:  5FEB2021 131033    56.0N  156.0W 3.0-4.6 CBAAA  Alaska Peninsula           

P: 17FEB2021 131321    54.7N  156.9W 3.5-4.8 BCAAA  Alaska Peninsula           

 

A moderate M 4.4 earthquake occurred in the region of Alberta Canada today. NEIC reported it was felt with maximum intensity IV in Alberta at Banff, Canmore, Chateau Lake Louise and I-II in Cochrane, Calgary, Airdrie, Okotoks, Leduc, Devon and in British Colombia  at Golden. Earthquakes Canada also reported this event was felt in the Banff area of Alberta. This is the strongest earthquake in the Banff area of Alberta within about 200 km in the past 30 years. The largest previous earthquakes in this area in this time period were of M 4.3 on March 10, 2019 and August 9, 2014 and an M 4.2 on May 19, 1996.  Forecast 131322 had expected today's event in Alberta was likely within about 100 km of this epicenter around February 17. This epicenter is at 103 degrees from the M 7.0 in Mindanao of January 21 and may have been promoted by energy from that source.

 

O: 14FEB2021 01:33:11  51.2N  115.6W MB=3.9  ECAN Banff, AB. Felt   

O: 14FEB2021 01:33:10  51.2N  115.6W mb=4.4  EMSC   ALBERTA, CANADA              

P: 17FEB2021 131322    52.0N  115.0W 2.0-4.2 BAAAA  Alberta                    

 

The strongest earthquake in the western hemisphere today was an M 5.2 in Northern Chile. NEIC reported it was felt with intensity IV in Iquique, Tarapaca, Chile. This earthquake is at 147 degrees from the event in Honshu of M 7.7 and may have been promoted by concentrated energy from that source. Forecasts 131384 and 131391 had expected this event within about 75 km was likely between February 12 and 16.

 

GUC reported this earthquake was felt with intensity  IV in  Tarapaca at Alto Hospicio, Iquique, Pozo Almonte; III in Huara, Pica, Pisagua, II in Camina and Ujina and III in Antofagasta at Quillagua, Chile. This epicenter is at 105 degrees from the Loyalty Islands and  at 145 degrees  from the M 7.1 in Honshu, Japan and may have been promoted by energy from those regions.

 

O: 13FEB2021 18:49:42  20.5S   70.6W Mw=5.2  EMSC   OFFSHORE TARAPACA, CHILE

O: 13FEB2021 18:49     20.5S   70.6W mb=5.2  GUC    Tarapaca at Alto Hospicio, Iqu

P: 12FEB2021 131384    21.0S   69.0W 4.0-5.6 AABAA  Coast No. Chile            

P: 16FEB2021 131391    20.0S   71.0W 4.0-5.4 BAAAA  So. Peru/Bolivia           

 

STRONG QUAKE SHAKES TAJIKISTAN; INDIA

 

EARTHQUAKE SUMMARY FOR FEBRUARY 12, 2021

 

A strong earthquake of M 5.9-6.3 shook the region of Tajikistan today.

The epicenter is in a remote area of southeastern Tajikistan in the Badakhstan National Park. CENC reported this earthquake at 38.1N 73.6E with M 6.1 at a depth of 100 km. The Indian National Centre for Seismology (NCS) reported M 6.3 for this quake. EMSC reported it was felt with moderate intensity in India at Uri, Srinigar, Delhi, Uttarakhand, Himachal Pradesh, Haryana, and in Shupiyan among others. It was also felt in Salor and Tashkent, Uzbekistan, in Kabul, Afghanistan, and in Kashgar Prefecture, China. This event at intermediate depth was widely felt in Central Asia with NEIC giving maximum intensity VIII in Murgob and Karakendzha, Tajikistan and IV in Dushanbe, and in Pakistan in Hunza, Gilgit, Mingaora, and V in Muzafferabad, Mansehra as well as in Baramula, Jammu and Kashmir, India. Internet photos showed some damage in the areas near the epicenter including cracked buildings and damaged roadways.

 

The area had been expected to see strongly enhanced seismicity at this time as this is an interesting event from the triggering point of view.  It is located within a degree of the maximum tidal stress longitude given by the tidal forecast in previous issues of this summary (75E vs 74E) near local solar midnight, a time when such stresses are maximized, and was probably strongly promoted by tidal effects. This was previously noted in previous issues of this summary as possible:

 

"The new moon arrived at 19:06 on February 11, 2021. Longitudes which are at local solar noon at this time are near 105W and 75E. In the west these include western North America and portions of the East Pacific Rise and in the east portions of the central Indian Ocean and Central Asia near Hindu Kush and Afghanistan among others. These areas are most likely to see tidal triggering in the next week. A large earthquake is possible in this time and tidal triggering is not limited to these regions." (February 8-12, 2021)

 

Furthermore, it is also near the antipode of the M 6.7 in the West Chile Rise M 6.7 of February 3 and at 104-106 degrees from the activity in the Loyalty Islands of February 10, a distance at which strong aftershock activity is expected following major earthquakes due to reflection and refraction of energy to the surface off the core-mantle boundary. This possibility had been noted in the FFA forecast for the Loyalty Islands on February 11-12, 2021 as:

 

 

"Far field triggering from the activity in the Loyalty Islands is expected to be robust. This is due, not only to the great size of the mainshock but also to the regions which are near 103 degrees from this epicenter. Areas at 103 degrees from the Loyalty Islands include western Canada, Oklahoma in the U.S. Oaxaca, Chiapas, Mexico, Guatemala, Panama, Ecuador, Peru, Chile in South America, India, China, Afghanistan in Asia." (February 11-12, 2021)

 

Other events near 103 degrees from the Loyalty Islands today of moderate magnitude occurred in Oklahoma, El Salvador, Texas, Chiapas, Mexico, Oaxaca, Mexico, Central Chile. When an M 4.6 regional foreshock occurred in Tajikistan yesterday, this summary noted:

 

 

"An M 4.6 also shook the region of Tajikistan today. This epicenter is near

104 degrees from the Loyalty Islands, as noted above and is also at the maximum tidal stress longitude with the new moon and occurred within about an hour of local solar midnight, a prime time for tidal triggering." (February 11-12, 2021)

 

The last earthquake in the area of Tajikistan within about 150 km of this epicenter with M>=5.9 was an M 6.6 on November 25, 2016. The last within about 100 km of this was an M 7.2 on December 7, 2015.  Forecast 131226 had expected today's event within about 50 km of this epicenter was likely around February 13-14.

 

O: 12FEB2021 10:15:20  38.5N   73.5E mb=4.0  EMSC   TAJIKISTAN

O: 12FEB2021 17:01:35  38.1N   73.6E Mw=5.9  EMSC   TAJIKISTAN                   

O: 12FEB2021 17:01:35  38.1N   73.6E Mw=6.1  CENC   TAJIKISTAN                   

O: 12FEB2021 17:01:35  38.1N   73.6E Mw=6.3  NSCC   TAJIKISTAN                   

P: 13FEB2021 131226    39.0N   72.0E 3.8-5.3 AAAAA  Hindu Kush/Pakistan        

P: 14FEB2021 131226    38.0N   74.0E 3.8-5.4 AAAAA  Hindu Kush/Pakistan        

 

A moderate earthquake of M 4.1 occurred today in the Fukushima area of Japan north of Tokyo. Recent activity in the area has included a number of moderate quakes in 2021, the largest of which was an M 4.8 on January 23, 2021. The  last earthquake of M>=5 was an M 5.5 on November 22, 2020 in association with a strong geomagnetic storm. This summary had noted at the time:

 

"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." (November 23, 2020)

 

Forecasts 130940 and 131242 had expected today's activity in early to mid-February. This area is near the sixth node (60 degrees) from the northern limit of the Loyalty Islands and may be subject to FFA triggering.

 

O: 12FEB2021 15:52:30  36.4N  141.1E ML=4.1  EMSC   NEAR EAST COAST OF HONSHU, JAP

P:  7FEB2021 130940    37.0N  142.0E 4.0-5.4 BAAAA  Off East Coast Honshu      

P: 14FEB2021 131242    38.0N  142.0E 4.0-5.5 ABAAA  Off East Coast Honshu      

 

The largest earthquake in the western hemisphere today was an M 5.2-5.3 in southern  Ecuador. NEIC reported it was felt with intensity II-III in Ecuador at Pueblo Viejo, Los Rios, and in Loja at Celica, Cariamanga and Loja. The last earthquake within about 200 of this epicenter with M>=5.2 was an M 5.5 on October 18, 2020 and a similar event on August 25, 2020. A major earthquake of M 7.5 hit the region about 300 km northeast of this on February 22, 2019. Like the event in Tajikistan this epicenter is at 104 degrees from the M 7.7 in the Loyalty Islands and was probably promoted by energy from that source. Forecast 131131 had expected today's event within about 25 km was likely around February 11.

 

O: 13FEB2021 05:18:33   4.1S   80.2W Mw=5.2  EMSC   PERU-ECUADOR BORDER REGION   

O: 13FEB2021 05:18:33   4.1S   80.2W Mw=5.3  ANSS   PERU-ECUADOR BORDER REGION   

P: 11FEB2021 131131     4.0S   80.0W 4.0-5.8 AAAAA  Ecuador                    

 

The largest earthquake today in the U.S. or Canada was an M 4.0 in Central California near Olancha. NEIC reported it was felt with intensity II-III in Central California in East Tulare County, Lone Pine, Inyokern, Kernville, Springville, Ridgecrest, Three Rivers, Lake Isabella, Trona and Bodfish.

It was followed by several felt aftershocks. This is the strongest event in the Ridgecrest, California aftershock zone since an M 3.9-4.0 on January 17, 2021. The last event within the Ridgecrest area with larger magnitude was an M 4.2 on June 4, 2020. A larger event of M 5.8 hit about 30 km north of this on June 24, 2020.  This activity is at the fourth node (90 degrees) from the Loyalty Islands M 7.7 of February 10 and was probably promoted by energy from that source. Forecast 131208 had expected  today's activity was likely within about 25 km around February 17.

 

O: 13FEB2021 00:23:35  35.6N  117.4W ML=2.6  EMSC   SOUTHERN CALIFORNIA           

O: 12FEB2021 18:34:01  35.6N  117.4W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 12FEB2021 23:57:12  36.2N  117.9W Mw=4.0  EMSC   CENTRAL CALIFORNIA           

O: 13FEB2021 00:08:35  36.2N  117.9W ML=2.5  EMSC   CENTRAL CALIFORNIA

O: 13FEB2021 00:11:51  36.2N  117.9W ML=2.8  EMSC   CENTRAL CALIFORNIA

O: 13FEB2021 02:06:39  36.2N  117.9W Ml=2.5  EMSC   CENTRAL CALIFORNIA

O: 13FEB2021 03:55:22  36.2N  117.9W ML=2.6  EMSC   CENTRAL CALIFORNIA

P: 17FEB2021 131208    36.1N  118.1W 2.5-4.3 BAAAA  California/Nevada area     

 

Moderate to large aftershocks also continued in the Loyalty Islands today. The largest of these was an M 5.9. These were not reported felt in this area. Forecast 131386 had expected this activity in mid-February.

 

O: 13FEB2021 05:15:21  23.0S  171.7E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 13FEB2021 05:19:51  23.1S  172.2E mb=4.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 07:49:34  23.2S  171.2E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 10:06:01  23.2S  171.6E mb=5.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 11:05:38  23.2S  171.7E Mw=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 10:34:13  23.3S  171.6E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 14:54:22  23.3S  171.9E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 20:55:15  23.3S  171.6E Mw=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 13FEB2021 05:09:12  23.3S  171.6E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 08:33:53  23.4S  171.1E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 10:04:03  22.5S  171.7E Mw=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 11FEB2021 131386    23.0S  172.0E 4.0-5.5 AAAAA  Loyalty Islands            

P: 14FEB2021 131386    22.0S  172.0E 4.0-5.3 AAAAA  Loyalty Islands            

P: 14FEB2021 131386    23.0S  171.0E 4.0-5.4 AAAAA  Loyalty Islands            

 

 

 

 

 

MODERATE LOYALTY ISLANDS AFTERSHOCKS CONTINUE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 11, 2021

 

Moderate to strong aftershocks continued today in the Loyalty Islands following the M 7.7 there on February 10. The mainshock triggered a minor tsunami which was observed in Norfolk Island to the south and may have been observed as far as New Zealand. Tsunami warnings were in place for areas as far as New Zealand and Lord Howe Island, Australia.

 

An omission occurred in the previous issue of this summary in terms of expected Far-Field Aftershocks (FFA). The antipode of the Loyalty Islands is in the Atlantic Ocean near the Islands of Madeira and Canary. This area has seen some unusual activity in recent days which may be related to the M 7.7 in the  Loyalty Islands area. The largest of these was an M 4.7 on January 30, 2021 in the Madeira Islands area. This summary had noted this at the time as:

 

"An unusually large earthquake of M 4.7 shook the Madeira Islands of Portugal today. The last earthquake of M>=4.7 in the Madeira Islands area within about 250 km of today's event was an M 5.2 on March 7, 2020, the only such event in the area in the past 30 years. ...  Today's activity follows a major swarm in the Granada, Spain region over the past four days. That swarm saw only minor events today and may be dying out. The M 4.7 in the Madeira Islands occurred within about an hour of local solar noon and may have been enhanced by tidal stresses of the full moon which maximize near this hour." (January 31, 2021)

 

Likewise the largest earthquake in the Canary Islands, near the antipode to the Loyalty Islands, in the past seven months was an M 3.2 on February 4, 2021. Two larger events have hit that area in the past year - an M 3.6 on May 27, 2020 and an M 3.9 on July 16, 2020. Either the Canary Islands or the Madeira Islands could see enhanced seismicity due to antipodal focusing of energy  from the Loyalty Islands M 7.7. Other unusual earthquakes in the antipodal area in the past two weeks included an M 5.7 in Guyana on January 31, 2021 – the largest ever recorded in this area - and an M 5.1 in Guinea on February 3, 2021.

 

O: 11FEB2021 19:45:21  28.0N   16.2W ML=1.8  EMSC   CANARY ISLANDS, SPAIN REGION 

 

The original far-field forecast for the Loyalty Islands in the previous issue of this summary was:

 

"Far field triggering from the activity in the Loyalty Islands is expected to be robust. This is due, not only to the great size of the mainshock but also to the regions which are near 103 degrees from this epicenter. Areas at 103 degrees from the Loyalty Islands include western Canada, Oklahoma in the U.S. Oaxaca, Chiapas, Mexico, Guatemala, Panama, Ecuador, Peru, Chile in South America, India, China, Afghanistan in Asia. Areas at 144 degrees from the Loyalty Islands include Turkey, Eastern Europe and Central Africa. These area may see enhanced seismicity in coming days. Other area subject to seismic promotion include Iran and the northern Caribbean (120 degrees node 3); Southern and Central California, Vancouver, southern Alaska, Myanmar, Mongolia (node 4, 90 degrees); East Pacific Rise, Sumatra, Taiwan, Hokkaido (node 5, 72 degrees); Izu Islands, Philippines, (node 6, 60 degrees) and Banda, Guam, New Guinea (node 5, 51 degrees) among others." (February 10-11, 2021)

 

The strongest aftershock since the last issue of this summary was an M 5.7 and 5.9 at 08:22 UT and 08:39 UT. These occurred in association with a strong Gamma

Ray Burst (GRB), as did the mainshocks yesterday. The parameters of that GRB as listed below as:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on February 11, 2021 at 08:43 UT with BAT Fluence  4.2e10-7 erg/cm2 (MAGNITUDE: n/a), Associated earthquake: Loyalty Islands, M 5.7 (08:40 UT); Western Turkey M 3.8 08:45 UT)" (February 11, 2021)

 

Forecasts 131386 had expected today's activity around February 11-14 within about 100 km of this activity.

 

O: 12FEB2021 03:47:48  22.5S  171.2E Mw=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 11:46:08  22.6S  171.1E mb=4.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 16:43:55  22.6S  171.1E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 19:20:39  22.6S  171.5E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 12:44:25  22.7S  171.2E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 20:05:53  22.7S  171.3E Mw=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 21:16:03  22.7S  171.4E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 16:52:35  22.8S  171.7E Mw=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 22:02:38  22.8S  171.6E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 07:23:05  22.9S  171.8E mb=5.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 08:22:10  22.9S  171.2E Mw=5.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 14:55:18  22.9S  171.8E Mw=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 07:18:40  23.0S  172.0E Mw=5.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 06:52:32  23.1S  171.6E Mw=6.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 11:19:26  23.1S  172.0E mb=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 16:13:54  23.1S  172.1E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 12:16:38  23.2S  171.9E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 07:56:04  23.3S  171.7E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 08:39:13  23.3S  171.7E Mw=5.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 17:21:08  23.3S  171.5E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 18:05:00  23.4S  171.8E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 04:06:05  23.4S  171.6E Mw=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 19:02:39  23.5S  171.9E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 12FEB2021 01:01:29  22.4S  171.3E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 11FEB2021 131386    23.0S  172.0E 4.0-5.5 AAAAA  Loyalty Islands            

P: 14FEB2021 131386    22.0S  172.0E 4.0-5.3 AAAAA  Loyalty Islands            

 

 

An earthquake of M 4.5-4.9 occurred today in the Cook Strait, New Zealand. NEIC reported this earthquake of M 4.5 in Cook Strait, New Zealand was felt with intensity IV in the area(s) of New Zealand in Wanganui and Foxton, North Island and II-III in Hawera, Levin, Kapiti, Wellington, Shannon, Porirua, Palmerston North, Makara-Ohariu and Upper Hutt.   GEONET reported this earthquake was felt with moderate intensity in Cook Strait and northern South Island. 5370 people reported feeling this event; 3460 with weak intensity; 1769 with light shaking; 126 moderate; 9 strong; 3 with severe and 3 with extreme shaking. The last earthquake of larger magnitude in the Cook Strait region was an M 5.0 and M 5.5 on May 26 and 24, 2020, the only such events in the past year. Forecast 131422 had expected today's event was likely within about 15 km was likely around February 14. It is likely this event was promoted by the M 7.7 in the Loyalty Islands.

 

O: 12FEB2021 03:54:10  40.1S  174.1E mb=4.5  EMSC   COOK STRAIT, NEW ZEALAND     

O: 12FEB2021 03:54:11  40.2S  174.1E ML=4.9  GEONET Felt with moderate intensity

P: 14FEB2021 131422    40.0S  174.0E 3.0-4.6 AAAAA  North Island, N.Z.         

 

Several moderate earthquakes were widely felt in the region of Turkey and Iran today. These areas had been expected to see FFA from the Loyalty Islands (see above). The most widely felt of these was an M 4.7 in Central Turkey but an M 4.9 in the Iran-Iraq border region was also felt.

 

The event in Central Turkey was located at 141 degrees from the Loyalty Islands M 7.7, a distance at which strong triggering is expected after major earthquakes as noted in the previous issue of this summary. Similar earthquakes hit this region with M 4.7-4.8 on September 14 and February 12, 2019 and on April 7, 2018 (M 4.7) but the last of larger magnitude within about 150 km of this epicenter was an M 5.0 on November 24, 2013. Forecast 131299 had expected today's event was likely around February 11.  

 

NEIC reported this earthquake of M 4.6-4.7 in Western Turkey was felt with intensity II-III in the area(s) of Western Turkey at Kastamonu and Safranbolu, Karabuk.

 

O: 12FEB2021 03:37:55  41.4N   33.5E mb=4.7  EMSC   CENTRAL TURKEY               

P: 11FEB2021 131299    41.0N   33.0E 3.5-5.1 AAAAA  No. Turkey/Black Sea       

 

The last earthquake of larger magnitude in the Iran-Iraq border within about

150 km of today's event was an M 5.3 on May 11, 2019. Forecasts 130933 and 131237 had expected today's activity was likely around February 10-11.

 

NEIC reported this earthquake of M 4.9 in Iran/Iraq was felt with intensity II-III in the area(s) of Iran in Kermanshah at Gilan Erab, Poke-Zahab and Aslamabad and in Eilam. 

 

O: 11FEB2021 23:22:21  34.7N   45.3E ML=3.6  EMSC   IRAN-IRAQ BORDER REGION      

O: 11FEB2021 22:10:43  34.8N   45.5E mb=4.9  EMSC   IRAN-IRAQ BORDER REGION

P: 10FEB2021 130933    36.0N   46.0E 3.8-5.4 ABAAA  No. Iran                   

P: 11FEB2021 131237    36.0N   46.0E 3.8-5.4 ABAAA  No. Iran                   

 

EMSC also reported an earthquake of M 3.8 in Western Turkey  was felt with intensity II-III in the area(s) of  Turkey at Candarli, Aliaga, Yenisakran, Menemen, Bergama, Karsivaka among others.  Forecast 131005 had expected this activity was likely around February 9. This earthquake was located at 143 degrees from the Loyalty Islands and was probably promoted from that source.

 

O: 11FEB2021 07:36:25  40.7N   30.6E ML=3.7  EMSC   WESTERN TURKEY               

P:  9FEB2021 131005    41.0N   29.0E 3.0-5.1 AAAAA  Romania/NW Turkey          

 

An M 4.6 also shook the region of Tajikistan today. This epicenter is near 104 degrees from the Loyalty Islands, as noted above and is also at the maximum tidal stress longitude with the new moon and occurred within about an hour of local solar midnight, a prime time for tidal triggering. This summary had expected enhanced tidal triggering with this new moon in previous issues as:

 

"The new moon arrived at 19:06 on February 11, 2021. Longitudes which are at local solar noon at this time are near 105W and 75E. In the west these include western North America and portions of the East Pacific Rise and in the east portions of the central Indian Ocean and Central Asia near Hindu Kush and Afghanistan among others. These areas are most likely to see tidal triggering in the next week. A large earthquake is possible in this time and tidal triggering is not limited to these regions." (February 8-12, 2021)

 

O: 11FEB2021 19:34:00  37.4N   72.0E mb=4.6  EMSC   TAJIKISTAN                   

P: 13FEB2021 131226    39.0N   72.0E 3.8-5.3 AAAAA  Hindu Kush/Pakistan        

P: 14FEB2021 131226    37.0N   71.0E 3.8-5.5 BAAAA  Hindu Kush/Pakistan        

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the Kodiak Island region of Alaska. NEIC reported this earthquake of M 4.0-4.4 in Kodiak, Alaska was felt with intensity II-III in the area(s) of Kodiak, Alaska and in Homer, Alaska. This is the largest earthquake in the Kodiak area since an M 4.9 about 150 km  southwest of this epicenter occurred on January 3, 2021 and prior to that an M 5.1 on July 8, 2020. Forecast 131345 had expected a moderate quake in this area was possible around February 13.

 

O: 11FEB2021 20:08:51  58.6N  153.5W mb=4.4  EMSC   KODIAK ISLAND REGION, ALASKA 

P: 13FEB2021 131345    60.0N  153.5W 3.2-5.3 ABAAA  Central Alaska             

 

An unusual earthquake of M 2.9 occurred today in the area of northern Virginia.

NEIC reported this earthquake of M 2.9 in Northern Virginia was felt with intensity II-III in the area(s) of Northern Virginia at Jewell Ridge, Richlands, Pounding Mill and Abingdon. An M 5.2 hit about 100 km southeast of this on August 9, 2020 but the last within this radius with M>=2.9 was an M 3.2 on September 13, 2017 and prior to that an M 3.4 on July 18, 2016. Forecast 131228 had expected today's activity within about 10 km was likely around February 16.

 

O: 12FEB2021 03:54:52  37.2N   81.8W mb=2.9  EMSC   VIRGINIA                     

P: 16FEB2021 131228    37.2N   81.9W 2.0-4.1 BAAAA  Kentucky/Tennessee/NC      

 

MAJOR QUAKE STRIKES LOYALTY ISLANDS; FFA LIKELY

 

EARTHQUAKE SUMMARY FOR FEBRUARY 10, 2021

 

A major quake of M 7.7 was preceded by a series of strong foreshocks and followed by a number of large aftershocks today. NEIC reported the mainshock was felt with intensity VII in Mont-Dore and V in Vao Sud, New Caledonia and in Shefa, Vanuatu with III. The mainshock of M 7.7 is the strongest earthquake in the Loyalty Islands within about 300 km of this epicenter since an M 7.7 on May 16, 1995. No larger events have hit the region in historical times (more than 100 years).  This is also the strongest earthquake in the world since events of M 7.7-7.8 west of Cuba on January 28, 2020 and the Alaska Peninsula on July 22, 2020. The last earthquake in the world of larger magnitude was an M 8.0 on May 26, 2019.

 

This activity occurred at a time when a number of stresses were enhancing seismicity in the region. These included the new moon tides, a strong Gamma Ray Burst (GRB),  the strongest solar flare since mid-January, a series of Tropical Cyclones and generally increased regional seismicity.

 

Today's activity in the Loyalty Islands was likely promoted by strong tidal stresses associated with the new moon as noted in this summary in previous issues:

 

"The new moon will arrive at 19:06 on February 11, 2021. Longitudes which are at local solar noon at this time are near 105W and 75E. In the west these include western North America and portions of the East Pacific Rise and in the east portions of the central Indian Ocean and Central Asia near Hindu Kush and Afghanistan among others. These areas are most likely to see tidal triggering in the next week. A large earthquake is possible in this time and tidal triggering is not limited to these regions." (February 8-10, 2021)

 

This activity began with an M 6.0 at 12:24 UT in the Loyalty Islands on February 10. This is within about 10 minutes of local solar midnight, a time when tidal stresses are maximized. The major aftershocks of this event occurred within

 the next hour and were also probably enhanced by tidal stresses.

 

Another factor contributing to today's activity was a pair of recent Tropical Cyclones which passed over these epicenter. When this series of earthquakes in the Loyalty Islands began on February 2, 2021, this summary had noted this as:

 

 

Moderate earthquake occur on a daily basis around the world. Likewise, tropical cyclones are not uncommon. It is when these events intersect that the geophysics gets interesting. Such was the case today. In the previous issue of this report it was noted:

 

"As noted in previous issues of this summary several tropical cyclones are currently in the area of Samoa, Vanuatu and the Loyalty Islands. This is an area where strong cyclones can and often do, trigger moderate seismicity. Although this area did not see any moderate events today, watch for some in the next several days." (February 1-2, 2021)

 

"Tropical cyclone Lucas (17P) continued in the region of Southern Vanuatu with winds up to 50 kts. It is expected to track to the south over the next week reaching the Loyalty Islands and southern Vanuatu around February 1-2. Some seismic enhancement may occur in Vanuatu while this storm is in the area." (February 1, 2021)

 

and

 

"Tropical Cyclone Bima (16P) continued west of Samoa today with winds up to 50 kts. It is expected to track to the east over the next several days reaching Samoa around February 1-2. Some regional seismicity in Samoa and Tonga may be enhanced while this storm is in the area." (February 1, 2021)

 

Today a series of moderately large earthquakes hit the Loyalty Islands as Tropical Cyclone Lucas passed over these epicenter and in Fiji as Tropical Cyclone Bima passed over that epicenter. These earthquakes were almost certainly triggered by stresses from these tropical cyclones.

 

The center of TC Lucas had been placed on February 3 in the Loyalty Islands at:

 

TC    LUCAS    2021-02-03  00:00 UT  21.9S  168.1E   50 kts  Loyalty Islands

 

The earthquakes in the area southeast of the Loyalty Islands occurred within an hour either side of local solar noon, a time for maximum tidal and geomagnetic triggering. This area is near the geomagnetic equator. The combination of these stresses and the passing of TC Lucas through the area at this time probably triggered today's activity. The last earthquakes of M>=5.7 within about 250 km of today's activity occurred on January 8, 2021 to the northeast and prior to that on September 6, 2019 with M 6.1 and 5.9 respectively. Forecast 131080 had expected this activity was likely around February 3-6, 2021. This activity is at 145 degrees from the Dodecanese M 7.0 of October 30, 2020; the seventh node (51.4 degrees) from the M 7.0 in Mindanao, Philippines of January 21, 2021 and may have been promoted by energy from this source." (February 3, 2021)

 

A new tropical storm passed to the east of today's activity in the Loyalty Islands over the past two days as noted in previous summaries and probably contributed additional stress reaching the rupture limit of the major earthquake today as noted in previous issues:

 

"A tropical cyclone may be forming in the area of Tonga. This system is currently located at 21S 178W in Tonga and moving SSE with winds up to 30 kts. Regional seismicity is expected to be enhanced while this storm is in the area." (February 8, 2021)

 

and

 

"Tropical cyclone 20P  formed in the area of Tonga today with winds up to 50 kts. This system is moving SSE with winds up to 50 kts. Regional seismicity is expected to be enhanced while this storm is in the Tonga/Kermadec region." (February 10, 2021)

 

Effects from a major Gamma Ray Burst near local solar noon in the Loyalty Islands earlier in the day may also have affected the timing of today's activity. The preliminary parameters of this GRB are in this summary as:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on February 10, 2021 at 02:00 UT with BAT Fluence  n/a erg/cm2 (MAGNITUDE: >16.9), Associated earthquake: Loyalty Islands, M 7.7 ...)" (February 11, 2021)

 

A moderate solar flare also occurred at the time of the main activity in the Loyalty Islands with the following parameters. This flare began within about  15 minutes of local solar midnight, a time for maximum Solar Flare Effects (SFE) on seismicity. It is the largest recorded flare since a C1.4 on January 20, 2021 and among the largest of the current year. It may have helped contribute to the magnitude of this activity:

 

Flare #    START  MAX       END    CLASS     DATE    Flux (Jm-2)

#-------------------------------------------------------------------------------

 

 

6170       1142   1206      1217   B5.7      (February 10, 2021)   6.3E-04      

 

Far field triggering from the activity in the Loyalty Islands is expected to be robust. This is due, not only to the great size of the mainshock but also to the regions which are near 103 degrees from this epicenter. Areas at 103 degrees from the Loyalty Islands include western Canada, Oklahoma in the U.S. Oaxaca, Chiapas, Mexico, Guatemala, Panama, Ecuador, Peru, Chile in South America, India, China, Afghanistan in Asia. Areas at 144 degrees from the Loyalty Islands include Turkey, Eastern Europe and Central Africa. These area may see enhanced seismicity in coming days. Other areas subject to seismic promotion include Iran and the northern Caribbean (120 degrees node 3); Southern and Central California, Vancouver, southern Alaska, Myanmar, Mongolia (node 4, 90 degrees); East Pacific Rise, Sumatra, Taiwan, Hokkaido (node 5, 72 degrees); Izu Islands, Philippines, (node 6, 60 degrees) and Banda, Guam, New Guinea (node 5, 51 degrees) among others. Earthquakes today at the fifth node included an M 6.2 in Sumatra and an M 5.6 in the East Pacific Rise.

 

At least 50 moderate sized shocks were associated as foreshocks or aftershocks within the first day. This included strong events of M 6.2, 6.0, 6.5, 6.0, 6.0 and several of M 5.9. Forecasts 130088 130385 and 131384 had expected today's activity in early February.

 

O: 11FEB2021 04:58:51  22.4S  170.9E mb=4.8  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 12:32:10  22.6S  171.6E Mw=5.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 13:57:18  22.6S  171.5E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 18:36:42  22.6S  171.3E Mw=6.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 14:18:20  22.7S  171.8E mb=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 14:37:22  22.7S  171.5E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 14:59:39  22.7S  172.1E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 15:44:30  22.7S  171.5E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 16:53:54  22.7S  171.6E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 19:56:15  22.7S  171.4E Mw=5.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 22:38:09  22.7S  171.4E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 01:24:42  22.7S  171.6E mb=5.4  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 04:15:16  22.7S  171.0E Mw=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 12:24:21  22.8S  171.7E Mw=6.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 13:01:59  22.8S  171.6E Mw=6.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 14:30:25  22.8S  172.1E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 16:52:20  22.8S  171.6E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 17:00:50  22.8S  171.3E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 17:25:54  22.8S  171.6E mb=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 20:45:20  22.8S  171.2E Mw=5.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:57:14  22.8S  171.3E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 23:32:46  22.8S  171.8E Mw=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 17:30:23  22.9S  179.8W mb=4.8  EMSC   SOUTH OF FIJI ISLANDS

O: 11FEB2021 00:13:20  22.9S  171.3E mb=4.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:17:50  23.0S  171.5E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:17:50  23.0S  171.5E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 20:10:35  23.1S  171.8E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 22:54:20  23.1S  171.7E mb=5.4  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 23:45:19  23.1S  171.6E Mw=5.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 00:14:47  23.1S  171.8E Mw=5.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 06:52:32  23.1S  171.6E Mw=6.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 19:13:58  23.2S  171.9E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:24:01  23.2S  171.6E Mw=6.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:40:34  23.2S  171.6E mb=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 22:03:43  23.2S  171.6E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 23:26:31  23.2S  171.9E Mw=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 23:43:21  23.2S  171.7E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 01:02:04  23.2S  171.7E Mw=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 11FEB2021 02:24:20  23.2S  171.7E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 13:19:59  23.3S  171.5E Mw=7.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 17:24:35  23.3S  171.5E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 20:41:39  23.3S  171.8E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 19:00:18  23.5S  171.7E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:36:03  23.5S  171.6E mb=5.5  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 21:50:04  23.5S  171.7E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 10FEB2021 14:50:02  22.4S  170.9E mb=5.1  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P:  1FEB2021 131088    20.0S  169.0E 4.0-5.3 CCBAA  Vanuatu Islands            

P: 11FEB2021 131386    23.0S  172.0E 4.0-5.5 AAAAA  Loyalty Islands            

P: 12FEB2021 131385    21.0S  170.0E 4.0-5.3 ABAAA  Loyalty Islands            

 

Several large earthquakes south of Sumatra followed the M 7.7 in the Loyalty

Islands and may have promoted by energy from that event. The strongest of these - an M 6.2 - followed the first of the Loyalty Islands shocks 28 minutes later at a distance of 71 degrees (node 5). S- waves and surface waves from the Sumatra event would have been present in Sumatra at the time of the follow=up M 6.0 there and may have helped trigger it. A series of moderate foreshocks and aftershocks occurred with the M 6.2 mainshock. The M 6.2 is the strongest earthquake in the region southwest of Sumatra within about 200 km since an M 6.8-6.9 on August 18, 2020 and prior to that an M 6.9 on August 2, 2019 and an M 6.4 on August 13, 2017. Forecasts 130847 and 131149 had expected today's activity was likely around February 6-11.

 

O: 10FEB2021 10:21:34   5.6S  101.8E mb=5.1  EMSC   SOUTHWEST OF SUMATRA, INDONESIA

O: 10FEB2021 12:52:28   5.6S  101.7E Mw=6.2  EMSC   SOUTHWEST OF SUMATRA, INDONESIA

O: 10FEB2021 10:15:37   5.7S  101.7E mb=5.1  EMSC   SOUTHWEST OF SUMATRA, INDONESIA

O: 10FEB2021 13:10:47   5.8S  101.9E ML=4.4  EMSC   SOUTHWEST OF SUMATRA, INDONESIA

O: 10FEB2021 13:17:38   5.8S  101.7E ML=4.2  EMSC   SOUTHWEST OF SUMATRA, INDONESIA

O: 10FEB2021 13:06:14   5.4S  102.6E ML=4.2  EMSC   SOUTHERN SUMATRA, INDONESIA  

P:  6FEB2021 130847     3.0S  103.0E 4.0-5.6 BCAAA  So. of Java                

P: 11FEB2021 131149     6.0S  102.0E 4.0-5.4 AAAAA  So. of Sumatera            

 

The largest earthquake in the U.S. or Canada today was an M 4.2-4.9 in the Yukon Territory, Canada. It was not reported felt widely in the epicentral area. The timing of this event within about 15 minutes of local solar noon suggests that tidal triggering was likely a promotional cause for this earthquake triggering. The last earthquake within about 200 km of this epicenter in Canada with equal or larger magnitude was an M 5.0 on December 22, 2017 and prior to that an M 5.1 on September 24, 2005. Forecasts 131052 and 131357 had expected this activity in this region was likely around February 8-16. This epicenter is at 104 degrees from the M 6.7 in the West Chile Rise of February 3 and may have been promoted by concentrated energy from that source.

 

O: 10FEB2021 21:18:49  64.5N  135.0W MB=4.7  ECAN OF ELSA, YT   

O: 10FEB2021 21:18:42  64.8N  133.7W MB=4.9  ECAN Keno, YT    

O: 10FEB2021 21:18:42  64.9N  133.7W Mw=4.2  EMSC   SOUTHERN YUKON TERRITORY, CANA

P:  8FEB2021 131052    64.0N  131.0W 2.5-4.3 AAAAA  Yukon Territory, Canada    

P: 16FEB2021 131357    65.0N  134.0W 2.5-3.9 CAAAA  Yukon Territory, Canada    

 

The strongest earthquake in the western hemisphere today was an M 5.6 in the Central East Pacific Rise. It was not reported felt in this remote epicentral area. This is the largest earthquake within about 300 km of this epicenter since an M 5.9 on July 7, 2015 and a similar M 5.7 on August 13, 2008. There have been no earthquakes of M>=6.0 in the area in the past 30 years.  The earthquake occurred within about an hour of local solar midnight and may have been promoted by strong tidal stresses associated with the new moon. Like the M 6.2 in Sumatra, this epicenter is located near the fifth node (72 degrees) from the Loyalty Islands.

 

O: 10FEB2021 08:22:31  13.6S  111.6W Mw=5.6  EMSC   CENTRAL EAST PACIFIC RISE    

 

SWARM IN SOUTHERN CALIFORNIA

 

EARTHQUAKE SUMMARY FOR FEBRUARY 9, 2021

 

A series of earthquakes occurred today in Southern California. The largest of these was of M 3.8 and M 3.8 in the region of Calipatria, California and was felt with intensity II-III in Westmorland, Indian Wells, Palm Desert, La Mesa, Bonita and possibly Tucson, Arizona. This included at least 15 light earthquakes of M>=2. The M 3.8's are the strongest events in this series since an M 4.0 on January 4, 2021 and an M 3.9 on October 22, 2020. Forecast 130948 had expected today's activity was likely within about 25 km of this epicenter around February 10. This activity is at the fourth node from the recent series of moderate to strong earthquakes in the area south of the Loyalty Islands which included a series of moderately strong earthquakes of M 5.6, 5.7 and 5.7 on February 2-4. 2021. That swarm is continuing with an M 5.0 on February 7. This activity is located at the fifth node (72 degrees) from the M 6.7 in  the West Chile Rise of February 3, 2021 and at  101-102 degrees from the M 7.0 in the Dodecanese Islands of October 30, 2020 and may have been promoted by energy from  that source. An M 5.2 in the Banda Sea was also located at the distance from the Dodecanese Islands today.

 

O: 10FEB2021 05:14:33  33.0N  115.9W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 09FEB2021 11:51:25  33.1N  115.6W ML=2.9  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 03:45:05  33.1N  115.7W ML=2.8  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:01:15  33.2N  115.6W Mw=3.6  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:01:15  33.2N  115.6W Mw=3.8  ANSS   SOUTHERN CALIFORNIA

O: 10FEB2021 01:03:55  33.2N  115.6W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:05:54  33.2N  115.6W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:05:54  33.2N  115.6W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:20:30  33.2N  115.6W ML=2.0  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:25:07  33.2N  115.6W ML=2.7  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:27:09  33.2N  115.6W Mw=3.6  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 01:27:09  33.2N  115.6W Mw=3.8  ANSS   SOUTHERN CALIFORNIA

O: 10FEB2021 01:45:43  33.2N  115.6W ML=2.7  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 02:24:48  33.2N  115.6W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 02:26:10  33.2N  115.6W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 04:56:43  33.2N  115.6W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 10FEB2021 05:12:11  32.7N  115.8W Ml=2.2  EMSC   SOUTHERN CALIFORNIA          

P: 10FEB2021 130948    33.0N  115.9W 2.5-4.6 AAAAA  So. California             

 

The strongest earthquake in the U.S. or Canada today was an M 4.0 in western Texas near the New Mexico border. The only earthquake in the past year of greater magnitude within about 200 km of this epicenter was an M 5.0 on March 26, 2020. Today's event is probably an aftershock of that. Forecast 130944 had expected today's activity in western Texas was likely around February 8.

 

NEIC reported this earthquake of M 4.0 in Western Texas was felt with intensity II-III in the area(s) of Las Cruces, New Mexico.  This activity is located at 101-102 degrees from the M 7.1 in the South Shetland Islands of January 23, 2021 and may have been promoted by energy from that source.

 

O:  9FEB2021 09:21:13  31.7N  104.3W ML=4.0  EMSC   WESTERN TEXAS                

P:  8FEB2021 130944    32.5N  104.6W 2.0-4.2 AAAAA  SW U.S.A                   

 

An earthquake of M 4.6-4.8 in western Turkey was followed by an aftershock of M 4.2 today. This is the strongest earthquake within about 150 km of this epicenter in Turkey since an M 5.0 on July 27, 2011. Forecasts 130965 and 130964 had expected this activity was likely in early February.

 

NEIC reported this earthquake of M 4.8 in Western Turkey was felt with intensity VIII in the area(s) of  Tuzlukou, Konya, Turkey and VI in Aksehir, Turkey.

 

O: 09FEB2021 15:53:57  38.6N   31.7E ML=4.2  EMSC   WESTERN TURKEY

O:  9FEB2021 15:51:54  38.6N   31.6E ML=4.6  EMSC   WESTERN TURKEY               

O:  9FEB2021 15:51:54  38.6N   31.6E ML=4.8  ANSS   WESTERN TURKEY                

P:  4FEB2021 130965    39.0N   33.0E 3.5-5.2 BABAA  Turkey                     

P:  5FEB2021 130964    38.0N   29.0E 3.5-5.2 BBBAA  Turkey                     

 

The strongest earthquake in the world today was an M 5.2 in the Izu Islands of  southeastern Japan. It was not reported felt in the area. The last earthquake in the Izu Islands with M>5.2 was an M 5.9 north of this on October 3, 2020. An M 5.8 also occurred in the Izu Islands south of today's epicenter on July 30, 2020. Forecast 130938 had expected today's activity was likely around February 8.

 

O:  9FEB2021 07:07:57  31.3N  140.7E Mw=5.2  EMSC   IZU ISLANDS, JAPAN REGION    

P:  8FEB2021 130938    30.0N  141.0E 4.0-5.4 ABAAA  Off East Coast Honshu      

 

An M 5.2 also occurred in the Banda Sea, Indonesia today. It was followed by aftershocks of M 4.5 and 4.6. This follows a series of event in the Banda Sea

of M 4.3-4.5 on February 6-7 but the last event of M>=5.2 in the area was an M 6.3 on November 1, 2020. Forecast 130854 had expected this activity in the Banda Sea in early February. Despite the strong geomagnetic activity over the past several days and high tides associated with the new moon this area and the Southwestern Pacific were relatively quiet today. Quiet conditions, when they are not expected, can signal strain accumulation which could be released in a strong to major event with the new moon. This summary had noted the possible seismic activity at the time of the new moon in the previous summary as:

 

"The new moon will arrive at 19:06 on February 11, 2021. Longitudes which are at local solar noon at this time are near 105W and 75E. In the west these include western North America and portions of the East Pacific Rise and in the east portions of the central Indian Ocean and Central Asia near Hindu Kush and Afghanistan among others. These areas are most likely to see tidal triggering in the next week. A large earthquake is possible in this time and tidal triggering is not limited to these regions." (February 9, 2021)

 

While activity associated with the geomagnetic storm was expected as:

 

"The geomagnetic field saw stormy conditions today. The AP level was 21.  High latitude geomagnetic field saw quiet conditions with AP 31. This appears to continue the strongest geomagnetic storm since AP reached 37 on November 23, 2020 and prior to that September 24-29, 2020. Enhanced seismicity is expected near 90E and 90W longitudes, near the geomagnetic equator and at high latitudes with this storm over the next several days." (February 8, 2021)

 

O: 09FEB2021 12:47:32   6.5S  130.0E mb=4.5  EMSC   BANDA SEA

O: 09FEB2021 10:49:36   7.1S  130.6E ML=4.6  EMSC   KEP. TANIMBAR REGION, INDONESIA

O:  9FEB2021 07:24:47   6.5S  130.0E Mw=5.2  EMSC   BANDA SEA                    

P:  4FEB2021 130854     7.0S  130.0E 4.0-5.3 BAAAA  West Irian, PNG            

 

50 YEARS SINCE THE SAN FERNANDO EARTHQUAKE - SO. CALIFORNIA

 

EARTHQUAKE SUMMARY FOR FEBRUARY 8, 2021

 

Fifty years ago on February 9, 1971 near sunrise (6:00 PST), an earthquake of M 6.7 caused major damage in the San Fernando Valley west of Los Angeles. This was a watershed moment in regional seismic history. Twenty-three years later in January, 1994 the Northridge earthquake hit the same area with similar damage and magnitude. This summary maintained this may be part of a characteristic earthquake series and that a third such earthquake was likely in the late 2010's. But while there were some indications that the area was again reaching rupture, this earthquake has not recurred - yet. As it is overdue, however, it is prudent to maintain the supplies for a catastrophic earthquake and this would be  a good time to check how your supplies are holding up. This summary reported on the San Fernando Earthquake of 1971 (see HISTORY section of this summary) as:

 

 2  9 14  9 55 1971  34.411 -118.401   8 6.7   So. California

 

The San Fernando earthquake. Maximum intensity VI when the Olive View Hospital was destroyed.  58 killed of which 49 were at the San Fernando Veterans Ad. Hospital. More than 2,000 injured. Damage estimated at more than $500 million. The near-failure of the Lower Van Norman Dam caused evacuation of thousands. Electrical and utilities were completely disrupted. Ground faulting was observed in the San Fernando area and landslides were common. Highway overpasses, railroads, pipelines were severely damaged by slides. Roads were blocked by rockfalls.

 

An unusual earthquake of M 3.3-3.6 hit the Mount Hood  area of Oregon today. NEIC reported maximum intensity IV in Bingen, Washington and Government Camp and Mount Hood, Parkdale, Oregon. It was also felt with intensity II-III in Oregon at Hood River, Odell, Mosier, Cascade Locks, Rhododendrom and The Dalles, Oregon and Underwood, Washington. As this event follows an M 2.8 in the Mount St. Helens area of Washington yesterday, it could indicate a broader volcanic or plutonic disturbance in the region. An M 2.2 follow up in the Mt. St. Helens area today had been forecast to occur around February 9 (131013). The event near Mt. Hood is the first within about 50 km of Mt. Hood with M>=3.3 since an M 3.3 on July 7, 2003. The only events in this region of M>=3.6 in the past 30 years were an M 4.5 on June 29, 2002 and an aftershock of M 3.8 on the same day. The earthquake on June 29, 2002 followed a day after the M 7.3 in Lander, Southern California (June 28, 1992) and was probably triggered by energy from that source. Forecast 131002 had expected today's event around February 10 within about 25 km of this epicenter. These events are located at 101 degrees from the Mindanao M 7.0 of January 21, 2021 and was probably promoted by energy from that source.

 

O:  9FEB2021 05:34:16  45.5N  121.6W ML=3.3  EMSC   OREGON                       

P: 10FEB2021 131002    45.3N  121.7W 2.0-4.1 AAAAA  Oregon state, U.S.         

 

O:  8FEB2021 16:00:41  46.0N  122.2W Md=2.4  EMSC   WASHINGTON                   

P:  9FEB2021 131013    46.9N  122.0W 2.0-4.3 AAAAA  Washington state, U.S.     

 

The strongest earthquake in the world today was an M 5.5 in New Britain, PNG. NEIC reported it was felt with intensity III in New Britain at Kokopo and Rabaul. This continues a series of moderately large and large earthquakes over the past several days in New Guinea, New Ireland and New Britain. These may be related to the strong geomagnetic storm over this period as this region is located on the geomagnetic equator. The last earthquake of M>=5.5 within about 200 km of today's epicenter was an M 5.8 on October 8, 2020. Forecast 130840  had expected today's activity was likely around February 9.

 

O:  9FEB2021 02:55:49   5.2S  151.7E Mw=5.5  EMSC   NEW BRITAIN REGION, P.N.G.   

P:  9FEB2021 130840     7.0S  151.0E 4.0-5.4 ABAAA  New Ireland                

 

An M 5.4 also occurred in the Kermadec Islands, New Zealand today. It was not reported felt in this remote area. It may have been promoted by the remnants of TC Lucas which was in the vicinity at the time of this event. The last earthquakes within about 200 km of this epicenter with M>=5.4 occurred a month ago on January 8, 2021 and prior to that an M 5.4 on January 10, 2020.  Forecast 131095 had expected today's event in this area around February 4.

 

O:  8FEB2021 08:06:18  30.3S  179.4W Mw=5.4  EMSC   KERMADEC ISLANDS REGION      

P:  4FEB2021 131095    30.0S  178.0W 4.0-5.5 BAAAA  No. Kermadec Islands       

P:  6FEB2021 131099    32.0S  179.0W 4.0-5.4 ABAAA  So. Kermadec Islands       

 

Moderate earthquakes continued to move closer to northern Taiwan today. These included events of M 5.4 and 5.2. NEIC reported maximum shaking with these was VI in Taiwan at Ilan; IV in Taipei and II-III in Hualien. CWB reported the earthquake of M 4.3 was felt with intensity II in Kinmen County, Taiwan.

The events of M 5.5 and 5.7 were reported felt with intensity IV in Yilan; III in Hualien, Taipei, Taoyuan, Nantou, Taipei, Taichung, Hsinchu, Miaoli, II in Hsinchu, Chinghua, Yunlin, Chiayi, Taitung, Tainan and Kaohsiung Counties, Taiwan. These appear to be aftershocks of the M 6.0 on December 10, 2020. The only other such event in the region in the past year was an M 5.7 on February 15, 2020. An M 5.3 hit the same area on February 6, 2021.  Forecast 130897 had expected today's activity within about 50 km was likely around February 10.

 

O:  8FEB2021 16:58:02  24.4N  122.1E Mw=5.4  EMSC   TAIWAN REGION                

O:  8FEB2021 16:56:30  24.4N  122.5E mb=5.1  EMSC   TAIWAN REGION                

O: 08FEB2021 16:58:03  24.4N  122.0E ML=5.7  TAI    Hualien, Taiwan              

O: 08FEB2021 16:56:31  24.4N  122.4E ML=5.5  TAI    Hualien, Taiwan              

O: 08FEB2021 15:34:01  24.2N  118.8E ML=4.3  TAI    Hualien, Taiwan              

P: 10FEB2021 130897    25.0N  122.0E 4.0-5.5 AAAAA  Ryukyu Islands             

 

The strongest earthquake in the U.S. or Canada today was an M 4.1-4.4 in Southeastern Alaska. NEIC reported intensity II-III for this event in Alaska at Yakutat, Elfin Cove, Douglas and Juneau. This is the strongest earthquake within about 200 km of this epicenter in the Yukon since an M 5.2 on December 18, 2019. Forecast 131038 had expected today's event within about 50 km around February 7. This epicenter is at 102 degrees from the M 6.7 in the West Chile Rise of February 3, 2021 and was probably promoted by concentrated energy from that source.

 

O: 08FEB2021 09:42:28  59.7N  137.5W MB=4.4  ECAN OF HAINES JUNCTION, YT  

O:  8FEB2021 09:42:21  59.4N  138.3W mb=4.1  EMSC   SOUTHEASTERN ALASKA          

O:  8FEB2021 11:52:09  59.4N  138.4W ML=3.6  EMSC   SOUTHEASTERN ALASKA          

P:  7FEB2021 131038    60.0N  138.0W 3.2-5.0 AAAAA  Central Alaska             

 

MODERATE AFTERSHOCKS CONTINUE IN MINDANAO, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 7, 2021

 

The strongest earthquake in the world today was an M 5.6 aftershock in the region of Southern Mindanao, Philippines. This follows the M 6.0 that occurred there yesterday and was covered in the previous issue of this summary as:

 

 

" ... an M 6.0 in Mindanao, Philippines. NEIC reported this earthquake was felt with damage in Southern Mindanao with intensity XI at Bansalan; VI in Goma, Digos, Kidapawan; VI in Kroondal; V in Padada, Davao and Malita and IV in Bato, and Ula, Mindanao, ... A foreshock of M 4.8 was felt with intensity II-III in Southern Mindanao, Bato, Davao and Panabo. Another foreshock to the north of M 4.6 was felt with intensity III in Cancocotan, Mindanao. This is probably a regional aftershock of the M 7.0 southwest of this that occurred January 21, 2021. Forecast 130825 had expected this activity was likely around February 7.  This activity is located at 143 degrees from the M 6.7 of December 27, 2020 in Los Lagos, Chile  and was probably promoted by energy concentration from these sources." (February 7, 2021)

 

NEIC reported this earthquake of M 5.6 in Mindanao, Philippines was felt with intensity II-III in the area(s) of Mindanao, Philippines at Davao and Libertad.

 

O: 08FEB2021 00:00:43   5.7N  127.1E Mw=5.6  EMSC   PHILIPPINE ISLANDS REGION

O:  7FEB2021 11:19:05   5.5N  126.3E mb=4.4  EMSC   MINDANAO, PHILIPPINES        

P:  7FEB2021 130825     5.0N  126.0E 4.0-5.3 AAAAA  Mindanao, Philippines      

 

The strongest earthquake today in the Western Hemisphere was an M 5.2 in Nicaragua. This is the largest earthquake within Nicaragua within about 150 km of this epicenter in at least 30 years. Most of the earthquakes in the region of  Nicaragua at this magnitude level occur about 150-200 km to the southwest of today's epicenter. Forecast 130874 had expected this event about 150 km south of this epicenter was likely around February 3. This epicenter is at 142 degrees from the M 7.0 in Mindanao, Philippines of January 21 and may have been promoted by energy from that source.

 

O:  7FEB2021 18:02:51  13.4N   85.8W ML=5.2  EMSC   NICARAGUA                    

P:  3FEB2021 130874    12.0N   86.0W 3.5-5.6 BBAAA  Nicaragua                  

 

An unusual earthquake of M 3.9 occurred northeast of Australia in the Norfolk Island area. The remnants of Tropical Cyclone Lucas passed over this area several days ago after triggering a series of events north of this in the Loyalty Islands which has continuing moderate aftershocks still. Forecast 131080 had expected activity in this area was likely in early February.

 

O:  7FEB2021 12:26:31  27.1S  171.0E ML=3.9  EMSC   NORFOLK ISLAND, AUSTRALIA REGI

P:  6FEB2021 131080    23.0S  169.0E 4.0-5.4 ACBAA  Loyalty Islands             

 

An M 2.6-2.8 earthquake occurred today in the Mt. St. Helens area of Washington State. NEIC reported this earthquake of M 2.8 in Washington State was felt with intensity II-III in the area(s) of Washington State at Yacolt and Carnation.  The last earthquake in the Mt. St. Helens area of M>=2 was an M 2.4 on August 26, 2020. But the last earthquake in the area of M>=2.6 occurred nearly three years ago on May 28, 2018 with M 3.0. The last of significantly larger magnitude was an M 3.9 on January 3, 2018. Forecast 131013 had expected the area would seen enhanced seismicity around February 9. This epicenter is at the third node (120 degrees) from the South Shetland Islands M 7.1 of January 23, 2021 and at 101 degrees from the Mindanao quake of M 7.0 of January 21 and my have been enhanced by energy from those sources.

 

O:  7FEB2021 23:13:29  46.2N  122.1W Md=2.6  EMSC   MT. ST. HELENS AREA, WASHINGTO

O:  7FEB2021 23:13:29  46.2N  122.1W Md=2.8  ANSS   MT. ST. HELENS AREA, WASHINGTO

P:  9FEB2021 131013    46.9N  122.0W 2.0-4.3 AAAAA  Washington state, U.S.     

 

NEW GEOMAGNETIC STORM COMES WITH THREE STRONG EARTHQUAKES NEAR EQUATOR

 

EARTHQUAKE SUMMARY FOR FEBRUARY 6, 2021

 

A new geomagnetic storm, the strongest in the past three months, occurred today

maximizing at high latitudes near mid-UT day. This summary noted this event as:

 

"The geomagnetic field saw stormy conditions today. The AP level was 21.  High latitude geomagnetic field saw quiet conditions with AP 31. This appears to continue the strongest geomagnetic storm since AP reached 37 on November 23, 2020 and prior to that September 24-29, 2020. Enhanced seismicity is expected near 90E and 90W longitudes, near the geomagnetic equator and at high latitudes with this storm over the next several days." (February 6, 2021)

 

The three strong earthquakes today occurred near the geomagnetic equator around

90 East longitude with an M 6.3-6.5 in New Guinea; an M 5.3-6.0 in Taiwan and an M 6.0 in Mindanao, Philippines.

 

The strongest earthquake in the world today was an M 6.3-6.5 in Papua New Guinea. NEIC reported it was felt with intensity VII in Madang, PNG. This is the strongest event within about 200 km of this epicenter since an M 6.5 on November 7, 2017 and an M 6.6 on July 31, 2011. Forecast 130839 had expected today's event within about 50 km was likely in early February. The strongest earthquakes in this area in the past 30 years was of M 6.6 in August, 1997 and April, 2005.

 

O:  7FEB2021 05:45:53   3.4S  146.0E Mw=6.5  EMSC   NEAR N COAST OF NEW GUINEA, PN

P:  2FEB2021 130839     3.0S  146.0E 4.0-5.6 BAAAA  New Ireland                

 

The earthquake in New Guinea followed an M 6.0 in Mindanao, Philippines. NEIC reported this earthquake was felt with damage in Southern Mindanao with intensity XI at Bansalan; VI in Goma, Digos, Kidapawan; VI in Kroondal; V in Padada, Davao and Malita and IV in Bato, and Ula, Mindanao, PHIVOLCS reported inentsity VII in M'Lang, Makilala and Kabacan, Cotabato; VI in Isulan, Sultan Kudarat; V in Magasaysay, Dogos City, Hagonoy, Santa Cruz, Sulop, Bansalan and Matanao, Davao Del Sur, Pres. Roxas Arakan, Carmen, Kidapawan City, Matalam and Tulunan, Cotabato, Koronadal City, Banga, Tupi and Tampakan, South Cotabato, Malungon, Sarangani, Columbio, Sultan Kudarat and IV in Davao City and Padada, Davao Del Sur, Antipas, Banisilan, Midsayap, Cotobato, Alabel, Kiamba, Malapatan, Carangani, General Santos City, Noral Polomolok, South Cotabato; Bagumbayan, Esperanza, Lutayan, Palimbang, Pres. Quirino, Sen. Nimoy Aquino, Tacurong City, Sultan Kudarat and Don Carlos Bukidnon. A foreshock of M 4.8 was felt with intensity II-III in Southern Mindanao, Bato, Davao and Panabo.

Another foreshock to the north of M 4.6 was felt with intensity III in Cancocotan, Mindanao. This is probably a regional aftershock of the M 7.0 southwest of this that occurred January 21, 2021. Forecast 130825 had expected this activity was likely around February 7.  This activity is located at 143 degrees from the M 6.7 of December 27, 2020 in Los Lagos, Chile  and was probably promoted by energy concentration from these sources.

 

O: 07FEB2021 04:22:56   6.8N  125.2E Mw=6.0  EMSC   MINDANAO, PHILIPPINES

O: 06FEB2021 10:21:10   7.5N  126.7E mb=4.6  EMSC   MINDANAO, PHILIPPINES

O:  6FEB2021 23:28:53   6.8N  125.1E mb=4.8  EMSC   MINDANAO, PHILIPPINES        

P:  7FEB2021 130825     5.0N  126.0E 4.0-5.3 ABAAA  Mindanao, Philippines      

 

An earthquake of M 5.3-6.0 also occurred northeast of Taiwan today.

NEIC reported this earthquake of M 5.4 in Taiwan was felt with intensity II-III in the area(s) of Taiwan at Taipei, Taoyuan, Hsinchu, and Chiayi. CWB reported this earthquake at M 6.0 was felt with intensity IV in Yilan and Miaoli; III in Hualien, Taipei, Taoyuan, Hsinchu, III in Taipei, Taichung, Nantou, Taitung, Changhua, Yunlin, Chiayi, and I in Kaohsiung Counties, Taiwan. This earthquake occurred near local solar midnight and may have been promoted by tidal and/or geomagnetic effects which maximize at this hour. The last earthquake within about 150 km of this epicenter with M>=6 was an M  6.1 on December 10, 2020. An M 6.1 also hit the area on April 17, 2019. The last of significantly larger event was an M 6.4 on February 6, 2018 exactly three years ago. Forecast 130902 had expected today's event within about 50 km was likely in Taiwan around February 4. This activity is located at 144 degrees from the M 6.7 in the West Chile Rise of February 3, 2021 and the M 7.1 of January 23, 2021 in the South Shetland Islands and was probably promoted by energy concentration from these sources.

 

O:  6FEB2021 17:36:02  24.7N  122.6E mb=5.3  EMSC   TAIWAN REGION                

O:  6FEB2021 17:36:03  24.7N  122.6E ML=6.0  TAI    Hualien, Taiwan              

P:  4FEB2021 130902    24.0N  123.0E 4.0-5.6 AAAAA  Taiwan                     

 

The strongest earthquake in the U.S. or Canada today was an M 4.9 in the western Alaska Peninsula. The last earthquakes within about 150 km of this epicenter of M>=4.9 occurred on January 24, 2021 with M 5.1 and before that an M 5.3 on December 16, 2020. Forecast 131035 had expected today's event within about 10  km was likely around February 4.  This activity is located at 143 degrees from the M 7.1 of January 23, 2021 in the South Shetland Islands and was probably promoted by energy concentration from these sources.

 

O:  6FEB2021 18:39:50  54.7N  161.2W mb=4.9  EMSC   ALASKA PENINSULA             

P:  4FEB2021 131035    54.7N  161.2W 3.5-5.1 AAAAA  Unimak Islands, Aleutians  

 

MODERATE QUAKE IN ARMENIA AFTER GRB

 

EARTHQUAKE SUMMARY FOR FEBRUARY 5, 2021

 

The most strongly felt earthquake in the world today was an M 5.1 in Armenia. NEIC reported maximum shaking of VII (slight Damage) in Armenia at Vahan and Gedebey, with IV in Arinj, Kotayk and II-III intensity at Jrvesh, Yerevan, Proshyan, Nor Kesaria, Armenia and in Igdir, Turkey, Tblisi, Georgia. This followed the first major Gamma Ray Burst since January 19 and a strong series of minor earthquakes in Germany several hours after the Gamma Ray burst but before the Armenian quake. The preliminary parameters of the GRB are:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on February 05, 2021 at 11:11 UT with BAT Fluence n/a (MAGNITUDE: >19.4), Associated earthquake: Armenia 2-5 15:36 UT M 5.1; strong swarm in Germany 12:00-14:00)" (February 5, 2021)

 

Armenia was near local solar noon when the GRB was first recorded. This appears to be the strongest earthquake within about 150 km of this epicenter in Armenia in the past 30 years. Forecast 130973 had expected today's activity was likely within this area around February 7, 2021.

 

O: 05FEB2021 15:48:13  40.5N   45.3E ML=4.2  EMSC   ARMENIA

O: 05FEB2021 20:06:38  40.5N   45.3E mb=4.0  EMSC   ARMENIA

O:  5FEB2021 15:36:09  40.5N   45.4E Mw=5.1  EMSC   ARMENIA                      

P:  7FEB2021 130973    40.0N   44.0E 3.5-5.3 AAAAA  Caucasus/Caspian Sea       

 

The M 3.2 is the strongest earthquake within about 100 km of this epicenter  in Germany was an M 3.4 on August 16, 2007. Forecast 130971 had expected activity in this area was likely to the southeast around February 7. This epicenter in Germany was within about 15 minutes of local solar noon when the GRB occurred at

11:11 UT and may have been promoted by that event. This activity is at the third node (120 degrees) from the South Shetland Islands event of January 23, 2021 and at 104 degrees from the Mindanao quake of January 21 and may have been promoted by energy from those sources.

 

O: 05FEB2021 14:14:12  47.8N    8.8E ML=3.2  EMSC   GERMANY

O: 05FEB2021 14:28:34  47.8N    8.8E ML=2.1  EMSC   GERMANY

O:  5FEB2021 13:58:37  47.8N    8.8E ML=2.0  EMSC   GERMANY                      

P:  7FEB2021 130971    47.0N   10.0E 3.0-5.1 AAAAA  Austria                    

 

An earthquake of M 4.7 was followed by an M 5.0 in the U.S. Virgin Islands today. NEIC reported these were felt with intensity II-III in the U.S. Virgin Islands at Saint John and Saint Thomas and in Road Town, Tortola, British Virgin Islands. They were also felt in Puerto Rico at Fajardo, Luquillo, Carolina, San Juan. While an M 5.4 occurred about 150 km south of this epicenter on January 24, 2021, the last event of M>=5.0 within about 100 km of this epicenter was an M 5.0 on October 6, 2019. The last of larger magnitude was an M 5.2 on November 12, 2011. Forecast 130885 had expected today's activity was likely around February 4, 2021. This activity is located at the sixth node (60 degrees) from the Los Lagos M 6.7 in Chile of December 27, 2020 and may have been promoted from that source.

 

O: 06FEB2021 07:05:02  19.1N   64.8W Mw=5.0  EMSC   VIRGIN ISLANDS REGION

O: 06FEB2021 07:11:16  19.1N   64.8W ML=3.8  EMSC   VIRGIN ISLANDS REGION

O: 06FEB2021 07:14:08  19.1N   64.8W ML=3.4  EMSC   VIRGIN ISLANDS REGION

O:  6FEB2021 06:56:11  19.1N   64.8W mb=4.7  EMSC   VIRGIN ISLANDS REGION        

P:  4FEB2021 130885    20.0N   64.0W 3.0-4.6 AAAAA  Bahamas/No. Caribbean      

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in Oklahoma. NEIC reported it was felt with maximum intensity VI in Oklahoma at Lucien and IV in Covington and Garber with II-III in Perry, Enid, Bison, Stillwater. Smaller foreshocks of M 3.5 and 3.7 and an aftershock of M 2.6 were also lightly felt in the Lucien area. The M 4,2 occurred within about an hour of local solar noon and may have been promoted by tidal stresses. The only other event of M>=4.2 in Oklahoma in the past year was an M 4.2 on June 21, 2020 with the solar eclipse of the same day.

 

The last event of M>=4.2 was an M 4.5 on January 19, 2020. With the M 4.2 in June this summary noted:

 

"A moderate earthquake of M 4.2 occurred today in northern Oklahoma. It was reported by NEIC to have been felt with intensity IV n Perry, Stillwater and Billings, Oklahoma and II-III in Much of northern Oklahoma and southern Kansas including in Oklahoma at Lucien, Covington, Garber, Morrison, Marshall, and in Kansas within about 300 km of the epicenter and in Missouri within about 400 km of the epicenter with intensity up to IV. Seismicity is often elevated in Oklahoma and Kansas at times of new moons. Tidal stresses probably promote movement of groundwater lubricating local small faults." (June 21, 2021)

 

Forecast 130962 had expected today's event was likely around February 4. This activity is located at the fifth node (72 degrees) from the West Chile Rise; 103 degrees from the South Shetland M 7.1 quake of January 23 and may have been promoted by energy from that source.

 

O: 05FEB2021 17:27:41  36.3N   97.5W ML=2.2  EMSC   OKLAHOMA

O: 05FEB2021 17:29:35  36.3N   97.5W ML=2.8  EMSC   OKLAHOMA

O: 05FEB2021 17:48:45  36.3N   97.5W Mw=4.2  EMSC   OKLAHOMA

O: 05FEB2021 17:59:13  36.3N   97.5W ML=2.8  EMSC   OKLAHOMA

O: 05FEB2021 18:03:22  36.3N   97.5W ML=2.5  EMSC   OKLAHOMA

O: 05FEB2021 18:14:06  36.3N   97.5W ML=2.1  EMSC   OKLAHOMA

O: 05FEB2021 19:59:51  36.3N   97.5W ML=2.1  EMSC   OKLAHOMA

O: 06FEB2021 00:40:38  36.3N   97.5W ML=2.0  EMSC   OKLAHOMA

O:  5FEB2021 16:17:37  36.3N   97.5W ML=3.4  EMSC   OKLAHOMA                     

P:  4FEB2021 130962    37.0N   97.0W 2.0-4.1 AAAAA  Southern Plains            

 

An earthquake of M 3.8 also shook the region of Southern Idaho today.  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 Lowman. The last earthquake of M>=3.8 in the southern Idaho aftershock zone was an M 4.0 about 30 km east of this on January 1, 2021 and prior to that an M 4.1 on December 11, 2020. Forecast 130985 had expected today's event was likely within about 10 km  of this epicenter was likely around February 6.  Like the activity today in Germany this event is located at 103 degrees from the Mindanao quake of January 21 and may have been promoted by energy from that source.

 

O: 05FEB2021 10:33:23  44.3N  115.2W Ml=2.6  EMSC   SOUTHERN IDAHO

O: 05FEB2021 14:08:41  44.3N  115.2W Ml=2.0  EMSC   SOUTHERN IDAHO

O:  5FEB2021 07:05:41  44.3N  115.2W Ml=3.8  EMSC   SOUTHERN IDAHO               

P:  6FEB2021 130985    44.4N  115.2W 2.0-4.2 AAAAA  Montana/Idaho              

 

 

MODERATE QUAKES SHAKE TAIWAN; LUZON PHILIPPINES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 4, 2021

 

The strongest earthquake in the world today was an M 5.7 in the area south of the Loyalty Islands where a strong swarm has been occurring over the past several days. In previous issues of this summary this had been addressed as:

 

 

"Today a series of moderately large earthquakes hit the Loyalty Islands as Tropical Cyclone Lucas passed over these epicenter and in Fiji as Tropical Cyclone Bima passed over that epicenter. These earthquakes were almost certainly triggered by stresses from these tropical cyclones." (February 3, 2021)

 

Forecast 131080 had expected today's event was likely to the west around February 6.

 

O:  4FEB2021 12:14:26  22.6S  172.0E Mw=5.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P:  6FEB2021 131080    23.0S  169.0E 4.0-5.4 AABAA  Loyalty Islands            

 

The strongest earthquake felt in the world today was an M 5.4 south of Taiwan. NEIC reported it was felt with intensity II-III in Kaohsiung and Taipei, Taiwan.

PHIVOLCS reported it was felt in the Philippines with intensity II in Itbayat, Batanes. CWB reported this earthquake was felt with intensity III in Taitung County, Taiwan. This is the strongest earthquake south of Taiwan within about 200 km of this epicenter since an M 5.9 on April 10, 2020. Forecast 130901 had expected today's event was like within about 100 km of this epicenter around February 6. This activity is at 143 degrees from the M 6.7 in the West Chile Rise of February 3 and was probably enhanced by concentrated energy from that source.

 

O: 04FEB2021 08:14:03  21.6N  122.0E Mw=5.4  EMSC   TAIWAN REGION

O:  4FEB2021 08:31:06  21.5N  121.7E ML=3.5  EMSC   TAIWAN REGION                

O:  4FEB2021 08:14:01  21.5N  121.9E ML=5.4  TAI    Hualien, Taiwan              

P:  6FEB2021 130901    22.0N  121.0E 4.0-5.3 AAAAA  Taiwan                     

 

PHIVOLCS reported an M 5.1 south of the in the Zambales area of northern Philippines several hours earlier was felt with intensity II in San Antonio, Zambales, Hermosa, Bataam and I in Castillejos and San Narciso, Zambales, Philippines. Forecast 130867 had expected this activity was likely around February 3.

 

An  earthquake of M 5.1 in Luzon, Philippines was also reported by PHIVOLCS to have been felt with intensity V in the Philippines at Vinzons, Daet, Jose Panganiban, Labo, Paracale and San Vicenter, Camarines Norte; IV in Capalonga, Camarines Norte, Sipocot, Camarines Sur; III in Iriga City, Naga City and Siruma, Camarines Sur; II in Goa Camarines Sur; Calauag, Quezon and I in Cainta and Tanay, Rizal. Several moderate aftershocks were also felt in this region. NEIC reported this earthquake of M  5.1 in Luzon, Philippines was felt with intensity VI in the area(s) of Luzon, Philippines in Bicol at Paracale and IV in Vinzons, Talisay with II-III in Daet, Calabanga, Caranan and in Malanday, Southern Tagalog.  Forecast 130868 had expected this activity was likely around February 5.

 

O:  4FEB2021 23:49:49  11.9N  120.9E mb=4.8  EMSC   PALAWAN, PHILIPPINES         

P:  5FEB2021 130867    12.0N  122.0E 3.5-4.8 AAAAA  Luzon, Philippines         

 

O:  4FEB2021 22:00:42  14.5N  123.1E Mw=5.1  EMSC   LUZON, PHILIPPINES           

P:  5FEB2021 130868    14.0N  125.0E 3.5-5.1 AABAA  Luzon, Philippines          

 

O:  4FEB2021 07:48:12  14.6N  118.9E Mw=5.1  EMSC   PHILIPPINE ISLANDS REGION    

P:  3FEB2021 130867    13.0N  121.0E 3.5-4.9 ABBAA  Luzon, Philippines         

 

An unusual earthquake of M 4.5 was lightly felt in the Kashmir and Xinjiang border today. This is the strongest earthquake within about 200 km of this epicenter since an M 5.0 on September 27, 2011. Similar sized event to today's of M 4.5 on March 7, 2020 and prior to that an M 4.5 on October 25, 2017. Forecast 130937 had expected today's event in this region was likely around February 4. This epicenter is within about 200 km of the exact antipode of the M 6.7 in the West Chile Rise of February 3, 2021. It may have been promoted by focused antipodal energy from that source.

 

O:  4FEB2021 17:02:02  36.7N   76.9E mb=4.5  EMSC   KASHMIR-XINJIANG BORDER REGION

P:  4FEB2021 130937    35.0N   78.0E 3.8-5.1 ABAAA  Northern India             

 

Activity also continued antipodal to the M 5.7 in Guyana in the region of Sulawesi, Indonesia today. The Guyana event was an M 5.7 on January 31 at 2.7N 59W. Today's events in  Sulawesi occurred at 2.8S 122E, within about 100 km of the exact antipode of Guyana and was probably enhanced by focused seismic energy from Guyana. Forecast 130849 had expected today's activity in Sulawesi around February 7.

 

O: 04FEB2021 17:39:49   2.8S  122.4E ML=4.1  EMSC   SULAWESI, INDONESIA

O:  4FEB2021 09:58:02   2.8S  122.3E ML=4.7  EMSC   SULAWESI, INDONESIA          

P:  7FEB2021 130849     2.0S  123.0E 4.0-5.4 BAAAA  Sulawesi area              

 

The strongest earthquake felt in the U.S. or Canada today was an M 2.9 in the region of Southern Colorado near Trinidad where it was lightly felt. This area became active a few days before 9-11, 2001 and has continued off and on since that time. The cause may be related to mining and/or water extraction in the area, but this has not been determinatively ascertained despite several studies. The area has been relatively quiet in the past year with the last event of

M>=2.9 recorded in this swarm occurring on  in Colorado as an M 3.1 on November 30, 2019.  Events in northern New Mexico near this epicenter have occurred with M 2.9-3.3 on May 16, December 23, 2020 and most recently as an M 2.9-3.0 on January 21, 2021.  Forecast 130918 had expected a light earthquake was possible within about 50 km of this epicenter around February 2.

 

O:  4FEB2021 14:08:38  37.0N  104.9W ML=2.9  EMSC   COLORADO                     

P:  2FEB2021 130918    37.4N  104.7W 2.0-4.1 AAAAA  Colorado area               

 

UNUSUAL QUAKE SHAKES GUINEA, EAST AFRICA

 

EARTHQUAKE SUMMARY FOR FEBRUARY 3, 2021

 

An unusual M 5.0 earthquake shook the area of Guinea in eastern North Africa today. NEIC reported maximum intensity IV in Guinea at Tondon and III in Conakry. This joins a series of moderate and large unprecedented earthquakes in the world over the past week. These have concentrated near the equator and the geomagnetic equator - in Guyana, northern South America, Australia, and the West Chile Rise. Today's earthquake in Guinea is the strongest in the past 30 years within about 400 km of this epicenter. The area has seen six earthquakes of M4.0-4.8 in the past 30 days, the largest of which was an M 4.8 on August 6, 2012. The last such event of M>=4 in the area was an M 4.2 on August 23, 2012. Seven events in the historical record, starting in May 20, 1795 in this region exceeded today's event in magnitude. The last was an M 5.3 on July 10, 1982 and the largest was an M 6.3-6.4 on December 22, 1983. This epicenter is at the fourth node (90 degrees) from the West Chile Rise quake of M 6.7 on February 3, 2021 and may have been promoted by energy from that source. It is also at the 8th node (45.0 degrees) from the Dodecanese Islands event of M 7.0 of October 30, 2020.

 

O:  3FEB2021 09:55:06  10.4N   12.9W mb=5.0  EMSC   GUINEA                       

 

The strongest earthquake in the world today was an M 5.3 in Eastern New Guinea, PNG. NEIC reported this earthquake of M 5.1-5.3 in  Lae Morobe, Papua New Guinea was felt with intensity II-III in the area(s) of  Lae Morobe, Papua New Guinea. This continues regional seismicity which began January 23 with events of M 5.6 and 5.7 and is probably an aftershock of that. Forecast 130841 had expected today's activity in early February within about 50 km of this epicenter. Other earthquakes near 103 degrees from the West Chile Rise today occurred as an M 4.9 in the North Atlantic Ridge, Central Alaska and west of Greenland, among others.

 

O:  3FEB2021 16:49:15   6.3S  147.5E Mw=5.3  EMSC   EASTERN NEW GUINEA REG., P.N.G

P:  2FEB2021 130841     7.0S  148.0E 4.0-5.5 AAAAA  New Ireland                

P:  6FEB2021 130841     6.0S  147.0E 4.0-5.4 BAAAA  New Ireland                

 

Two light earthquakes of M 2.6 and 2.2 rocked the Virginia-North Carolina Border today. NEIC reported maximum intensity IV in Sparta, North Carolina and II-III in North Carolina at Glade Valley, Laurel Springs, Ennice, Grassy Creek, State Road, West Jefferson and Elkin and in Virginia at Independence and Galax. This is the strongest activity in eastern Virginia near the North Carolina border since an M 3.2 on October 25, 2020. The last earthquake of M>=2.6 in Virginia was an M 2.6 on January 16, 2021 and prior to that an M 2.8 on November 9, 2020. These, and today's events are probably aftershocks of an M 5.2 at this epicenter which occurred on August 9, 2020. Forecast 130923 had expected the area of eastern North Carolina would see enhanced seismicity around February 4. This epicenter is at 101 degrees from the South Shetland Islands event of January 23 and may have  been promoted by energy from that source.

 

O: 04FEB2021 04:33:59  36.5N   81.1W Md=2.2  EMSC   VIRGINIA-N CAROLINA BORDER REG

O:  4FEB2021 04:03:04  36.5N   81.1W mb=2.6  EMSC   VIRGINIA-N CAROLINA BORDER REG

P:  4FEB2021 130923    37.0N   83.0W 2.0-4.1 AABAA  Kentucky/Tennessee/NC      

 

The strongest earthquake in the U.S. or Canada today was an M 3.7 in Southern California. It was followed by several lightly felt aftershocks. The mainshock was reported by NEIC to have been felt with intensity II-III in Southern California at Ocotillo, El Centro, Imperial, Calexico, Mexicali, Westmorland, Brawley, Julian and Borrego Springs and in Baja California at Puebla and Mexicali. NEIC reported an aftershock of M 2.8 in Southern California was felt with intensity II-III in the area(s) of Southern California at San Diego.  This continued elevated seismicity in the area associated with the M 7.1 in the South Shetland Islands quake of January 23, 2021. This activity is near 103 degrees from that epicenter, a distance at which energy is concentrated following large earthquakes and where strong triggering often occurs after such major earthquakes. The last earthquakes in this region of southern California of M>=3.7 occurred on January 4, 2021 and  December 22, 2020 following events in early October of M 4.5 and in early November, 2020 of M 3.7. Today's activity may have been affected by resonant energy associated with the nor'easter yesterday in the Northeastern U.S. as hypothesized in earlier issues of this summary. Forecast 130948 had expected today's activity within about 25 km was likely around February 2. This activity is located at the fifth node (72 degrees) from the West Chile Rise M 6.7 of February 3, and may have been promoted by energy from that source.

 

 

O: 03FEB2021 09:36:55  32.7N  115.8W ML=2.9  EMSC   SOUTHERN CALIFORNIA

O: 03FEB2021 09:42:45  32.7N  115.8W ML=2.6  EMSC   SOUTHERN CALIFORNIA

O: 03FEB2021 15:54:38  32.7N  115.8W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 03FEB2021 15:54:38  32.7N  115.8W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 03FEB2021 09:23:35  32.8N  115.8W Mw=3.7  EMSC   SOUTHERN CALIFORNIA

O: 03FEB2021 09:43:46  32.8N  115.8W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 04FEB2021 02:53:50  32.8N  115.8W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O:  3FEB2021 08:07:33  31.7N  116.0W ML=3.4  EMSC   BAJA CALIFORNIA, MEXICO      

O:  3FEB2021 08:11:43  32.5N  115.6W Ml=2.1  EMSC   BAJA CALIFORNIA, MEXICO      

P:  2FEB2021 130948    32.4N  115.8W 2.5-4.5 AAAAA  So. California             

 

 

The M 3.7 in Ocotillo, California followed a stronger M 4.9 in the Gulf of California south of this. NEIC reported it was felt with intensity II n Culiacan, Sinaloa, Mexico. This is the strongest earthquake in the western Hemisphere today. Two earthquakes of similar or larger magnitude have hit within about 200 km of this epicenter in the past two years - an M 5.3 on November 13, 2020 and an M 6.1 on May 22, 2020. Forecast 130888 had expected today's activity was likely around February 8. This event is at the sixth node (60 degrees) from the M 6.7 in the West Chile Rise of February 3 and may have been enhanced by energy from that event.

 

O:  3FEB2021 08:42:25  23.1N  108.0W mb=4.9  EMSC   GULF OF CALIFORNIA           

P:  8FEB2021 130888    24.0N  109.0W 3.5-4.9 BAAAA  Gulf of California         

 

 

CYCLONES TRIGGER MODERATELY STRONG QUAKES IN LOYALTY ISLANDS, FIJI

UNPRECEDENTED M 6.7 IN WEST CHILE RISE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 2, 2021

 

The strongest earthquake in the world today was an M 6.7, the strongest ever recorded within about 400 km of the epicenter in the West Chile Rise. But moderately strong earthquake also occurred in the Loyalty Islands and in the  Fiji Islands west of Samoa with M 5.5-6.0. These may be related to the strongest geomagnetic storm in more than two month as noted in this summary:

 

"The geomagnetic field saw active conditions today. The AP level was 17.  High latitude geomagnetic field saw stormy conditions with AP 37. This is the strongest geomagnetic storm since AP reached 37 on November 23, 2020 and prior to that September 24-29, 2020. Enhanced seismicity is expected near 90E and 90W longitudes, near the geomagnetic equator and at high latitudes with this storm over the next several days." (February 2, 2021)

 

Moderate earthquake occur on a daily basis around the world. Likewise, tropical cyclones are not uncommon. It is when these events intersect that the geophysics gets interesting. Such was the case today. In the previous issue of this report it was noted:

 

"As noted in previous issues of this summary several tropical cyclones are currently in the area of Samoa, Vanuatu and the Loyalty Islands. This is an area where strong cyclones can and often do, trigger moderate seismicity. Although this area did not see any moderate events today, watch for some in the next several days." (February 1-2, 2021)

 

"Tropical cyclone Lucas (17P) continued in the region of Southern Vanuatu with winds up to 50 kts. It is expected to track to the south over the next week reaching the Loyalty Islands and southern Vanuatu around February 1-2. Some seismic enhancement may occur in Vanuatu while this storm is in the area." (February 1, 2021)

 

and

 

"Tropical Cyclone Bima (16P) continued west of Samoa today with winds up to 50 kts. It is expected to track to the east over the next several days reaching Samoa around February 1-2. Some regional seismicity in Samoa and Tonga may be enhanced while this storm is in the area." (February 1, 2021)

 

Today a series of moderately large earthquakes hit the Loyalty Islands as Tropical Cyclone Lucas passed over these epicenter and in Fiji as Tropical Cyclone Bima passed over that epicenter. These earthquakes were almost certainly triggered by stresses from these tropical cyclones.

 

The center of TC Lucas had been placed on February 3 in the Loyalty Islands at:

 

TC    LUCAS    2021-02-03  00:00 UT  21.9S  168.1E   50 kts  Loyalty Islands

 

The earthquakes in the area southeast of the Loyalty Islands occurred within an hour either side of local solar noon, a time for maximum tidal and geomagnetic triggering. This area is near the geomagnetic equator. The combination of these stresses and the passing of TC Lucas through the area at this time probably triggered today's activity. The last earthquakes of M>=5.7 within about 250 km of today's activity occurred on January 8, 2021 to the northeast and prior to that on September 6, 2019 with M 6.1 and 5.9 respectively. Forecast 131080 had expected this activity was likely around February 3-6, 2021. This activity is at 145 degrees from the Dodecanese Islands M 7.0 of October 30, 2020; the seventh node (51.4 degrees) from the M 7.0 in Mindanao, Philippines of January 21, 2021 and may have been promoted by energy from this source.

 

O: 03FEB2021 00:42:18  22.6S  172.2E Mw=5.6  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 02FEB2021 23:50:41  22.7S  172.0E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 03FEB2021 00:05:33  22.7S  171.9E mb=5.2  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 03FEB2021 00:51:35  22.7S  172.0E mb=5.3  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 03FEB2021 01:44:33  22.7S  171.9E mb=4.9  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O: 03FEB2021 00:49:44  22.9S  171.9E mb=5.0  EMSC   SOUTHEAST OF LOYALTY ISLANDS

O:  2FEB2021 23:58:34  22.6S  172.1E Mw=5.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P:  3FEB2021 131080    21.0S  169.0E 4.0-5.4 ABBAA  Loyalty Islands            

P:  6FEB2021 131080    23.0S  169.0E 4.0-5.4 BABAA  Loyalty Islands            

 

The center of TC Bima had been placed on February 2 and 3 at:

 

TC    BIMA     2021-02-02  00:00 UT  15.6S  178.5E   45 kts  West of Samoa

TC    BIMA     2021-02-03  00:00 UT  15.6S  179.5E   45 kts  West of Samoa

 

The M 5.7 in Fiji preceded the activity in the Loyalty Islands by about three hours. This is the strongest earthquake within about 250 km of this epicenter in Fiji since an M 5.8 on August 29, 2018 and prior to that an M 5.9 on August 8, 2012. Forecast 131060 had expected this activity within about 100 km was likely around February 5.

 

NEIC reported this earthquake of M 5.7 in Fiji  was felt with intensity VII in the area(s) of  Fiji at Tavua, Western Fiji and  with III in Suva, Central Fiji.

 

O:  2FEB2021 20:49:27  16.2S  178.0E Mw=5.7  EMSC   FIJI                         

P:  5FEB2021 131060    17.0S  178.0E 4.0-5.4 BAAAA  Fiji Islands               

 

The strongest earthquake in the world today was an M 6.7 in the West Chile Rise. This follows the M 6.7 in the Los Lagos event of December 27, 2020. Both of these were located along the path of the total eclipse of the sun which occurred on December 14, 2020. Both were probably promoted by high tidal stresses. The next annular Solar Eclipse will be visible on June 10, 2021 and will be visible in northern North America including the northeastern U.S.

 

This earthquake is the strongest within about 400 km of this epicenter in at least the historical record for the area. Earthquakes in this area of M 6.5 hit on 1934, 1937, 1954, 1975, 1997 and 1999.   It occurred within about an hour of local solar midnight, a time when geomagnetic effects are prominent and may have been related to those as well as to tidal stresses which maximize near this hour. Forecast 131093 had expected today's event within about 50 km was likely around February 8 in the Chile Rise area. The antipode of this epicenter is in China north of Nepal at 36N 83E. Recent activity in Nepal including an M 4.6 today and an M 5.2 yesterday may be related.

 

O:  3FEB2021 05:23:44  36.2S   97.7W Mw=6.7  EMSC   WEST CHILE RISE              

P:  8FEB2021 131093    36.0S   97.0W 4.0-5.4 BAAAA  Chile Rise                 

 

 

MODERATE QUAKES IN MOZAMBIQUE, NEPAL AND TURKEY

 

EARTHQUAKE SUMMARY FOR FEBRUARY 1, 2021

 

The strongest earthquakes in the world today, on a relatively calm seismic

day occurred as an M 5.1 in Turkey and an M 5.2 in Nepal. An unusual series

of moderate quakes also occurred in northern Mozambique with M 4.2, 4.4, 4.3. The activity in Turkey was accompanied by other shocks of of M 4.6 and 4.7. This is follow-up activity to a series in the region yesterday described in this summary in the previous issue as:

 

 

"Three moderate earthquakes of M 4.8 were felt in Turkey today. These were reported by NEIC to have been felt with intensity II-III in Izmir, Turkey at Dikili, Karaburun, Izmir, Menderes, and in Ip;slaa Edirne and Silivri, Istanbul and in Greece at Marmarn, Khios, Hios. These are the strongest earthquakes within about 100 km of these epicenters since an M 6.3 on June 12, 2017 and an aftershock on June 17, 2017 of M 5.2. An M 7.0 hit the area about 150 km southeast of this epicenter on October 30, 2020. Forecast 130904 had expected today's activity was likely around February 3, 2021. This epicenter is located at the third node (120 degrees) from the South Shetland Islands event of January 23 and may have been promoted by energy from that source." (February 1, 2021)

 

NEIC reported this earthquake of M 4.5 in Turkey was felt with intensity II-III in the area(s) of Turkey at Kayseri and Sivas. Events of M 5.2, 4.8 and  M 4.9 earlier in the day were felt with intensity IV in Lesvos, Greece at Skoutaros, Moria, Mitilini, Eresos and Pamfila and in Izmir, Turkey and in Menderes, in Canakkale, Izmir, and in Balikesir at Balikesir, Edremil, Ayvalik.

 

O: 01FEB2021 13:10:15  39.0N   26.0E mb=4.7  EMSC   NEAR THE COAST OF WESTERN TURKEY

O: 01FEB2021 20:46:16  39.0N   26.1E Mw=4.6  EMSC   NEAR THE COAST OF WESTERN TURKEY

O:  1FEB2021 08:35:17  39.0N   26.1E mb=5.1  EMSC   NEAR THE COAST OF WESTERN TURK

P:  3FEB2021 130904    38.0N   26.0E 3.0-4.6 AAAAA  Aegean Sea                 

 

The largest earthquake in the world today - the M 5.2 in Nepal was lightly felt in that area. It is the largest reported in Nepal since an M 5.3 on September 15, 2020. NEIC reported this earthquake of M 5.2 in Nepal was felt with intensity II-III in the area(s) of Nepal at Lalitpur, Pokhara, Kaski. Forecast 130611 had expected today's activity to the south in Nepal around January 30.

 

O:  2FEB2021 02:31:15  28.9N   87.6E Mw=5.2  EMSC   WESTERN XIZANG               

P: 30JAN2021 130611    27.0N   88.0E 3.5-5.4 ABAAA  Nepal                       

 

A series of three moderate earthquakes also occurred today in northern Mozambique. Tropical Cyclone Eloise made landfall in this region about a week ago and probably helped promote today's activity as noted at the time in this summary:

 

"Tropical Cyclone Eloise continued today North of Madagascar with winds up to 80 kts. It made landfall today in northern Madagascar. A moderate earthquake in the Mayotte area accompanied landfall and was probably promoted by that event." (January 22, 2021)

 

Forecast 130784 had expected today's activity was likely within about 200 km  of this epicenter around January 28. The last earthquake of M>=4.4 within about 250 km of today's epicenter was an M 4.8 on July 26, 2020. This activity is at 144 degrees from the M 7.6 of October 19, 2020 in the Alaska Peninsula and at the fifth node (72 degrees) from the South Shetland Islands M 7.1 of January 23, 2021 and may have been promoted by strong energy concentration from those sources.

 

O: 01FEB2021 16:55:28  20.2S   33.0E mb=4.3  EMSC   MOZAMBIQUE

O: 01FEB2021 23:51:53  21.5S   34.9E mb=4.4  EMSC   MOZAMBIQUE

O:  2FEB2021 01:06:02  21.5S   34.9E mb=4.2  EMSC   MOZAMBIQUE                   

P: 28JAN2021 130784    22.0S   33.0E 4.0-5.6 BABAA  So. Indian Ocean           

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in Hawaii. NEIC reported it was felt with intensity IV in Papaikou and III in Pahoa, Mountain View, Volcano, Kurtistown, Hawaii National Park, Keaau, Hilo, Pepeekeo and Hakalau. The last earthquake of larger magnitude in Hawaii was an M 4.7 on January 15, 2021. Forecast 130864 had expected today's activity in early February, 2021.

 

O: 02FEB2021 00:13:10  19.4N  155.1W ML=4.1  EMSC   ISLAND OF HAWAII, HAWAII

O:  2FEB2021 05:43:56  19.2N  155.5W ML=3.1  EMSC   ISLAND OF HAWAII, HAWAII     

P:  2FEB2021 130864    18.8N  155.2W 3.0-4.5 AAAAA  Hawaii                     

P:  5FEB2021 130864    19.2N  155.2W 3.0-4.5 BAAAA  Hawaii                     

 

Coincidences happen!  Although this summary often stretches when apparent coincidences occur, there are times when they are just what they appear - simultaneous happenstances. Case in point is the M 2.8-2.9 off northern California today. Today is TWOSday (Tuesday) 2-2-2021 (2 February 2021). The strongest earthquake in California today was this M 2.9 of the coast of Northern California. It occurred at 02:22 UT (rounded) on 2-2-2002. The coast of California north to Vancouver B.C. could see a moderate earthquake in the next two days however. A strong nor'easter hit the northeastern U.S. today. Such storms are frequently accompanied by enhanced seismicity along the western Boundary of North America, perhaps through a resonance effect. Some of the strongest earthquakes in that area in recent years have occurred with strong hurricane and nor'easter strikes in northeastern U.S. This does not always happen, but is frequent enough to take note of.

 

NEIC reported this earthquake of M 2.8-2.9 off northern California  was felt with intensity II-III in the area(s) of northern California in Pleasant Hill.

 

Today's earthquake off the coast of Northern California had been expected to

occur around February 3 about 50 km east of today's epicenter (forecast 130997).

 

O:  2FEB2021 02:21:29  40.4N  125.7W ML=2.8  EMSC   OFF COAST OF NORTHERN CALIFORN

O:  2FEB2021 02:21:30  40.4N  125.7W ML=2.9  EMSC   OFF COAST OF NORTHERN CALIFORN

P:  3FEB2021 130997    40.6N  124.9W 2.5-4.9 AAAAA  Off Coast of No. Calif     

 

As noted in previous issues of this summary several tropical cyclones are currently in the area of Samoa, Vanuatu and the Loyalty Islands. This is an area where strong cyclones can and often do, trigger moderate seismicity. Although this area did not see any moderate events today, watch for some in the next several days.

 

"Tropical cyclone Lucas (17P) continued in the region of Southern Vanuatu with winds up to 50 kts. It is expected to track to the south over the next week reaching the Loyalty Islands and southern Vanuatu around February 1-2. Some seismic enhancement may occur in Vanuatu while this storm is in the area." (February 1, 2021)

 

and

 

"Tropical Cyclone Bima (16P) continued west of Samoa today with winds up to 50 kts. It is expected to track to the east over the next several days reaching Samoa around February 1-2. Some regional seismicity in Samoa and Tonga may be enhanced while this storm is in the area." (February 1, 2021)

 

UNPRECEDENTED EARTHQUAKE SHAKES GUYANA, NORTHEASTERN SOUTH AMERICA

 

EARTHQUAKE SUMMARY FOR JANUARY 31, 2021

 

An unprecedented earthquake of M 5.7 shook areas of southern Guyana, Brazil, Suriname and Venezuela today. NEIC reported this earthquake was felt with intensity IV in Guyana at Lethem and Mahalcony and in Venezuela at Ciudad Guayana Bolivar and Tucupita Delta Amacuro, Venezuela. Intensity II-III was also felt in Georgetown, Paradise, Anna Regina, Guyana and in Moengo, Suriname, and Manaus, Brazil. The M 5.7 was followed by a series of moderate aftershocks.  The only earthquake within about 300 km of today's epicenter recorded in history of M>=5.5 was recorded with M 5.5 on June 19, 1964 and again on August 15, 1965.

There have been no other events recorded in this area in at least 400 years. Forecast 130819 had expected today's activity was likely in early February. 

 

In the previous issue of this summary, this area had been pointed out as a potential area where antipodal triggering from activity north of Australia was possible at this time as:

 

"It was not pointed out that the largest earthquake in South America yesterday occurred as an M 4.7 in central Venezuela. This may have been promoted by antipodal focusing of energy from the Australia event. The M 5.6 in Australia, as noted above, combined with antipodal energy from the two Tropical Cyclones  and an M 5.6 in the Flores Sea of January 11 and an M 7.0 in southern Mindanao may have contributed additional antipodal energy to help activate the region of northern South America and the southern Windward Islands in the Caribbean which sees most of the regional activity in Trinidad and Tobago. With the full moon, this regional activation is likely to continue for several more days." (January 31, 2021)

 

O: 31JAN2021 19:22:52   2.5N   59.5W ML=2.9  EMSC   GUYANA

O: 31JAN2021 19:24:28   2.5N   59.5W ML=3.3  EMSC   GUYANA

O: 31JAN2021 19:32:28   2.5N   59.5W mb=4.2  EMSC   GUYANA

O: 31JAN2021 19:34:47   2.5N   59.5W ML=3.8  EMSC   GUYANA

O: 31JAN2021 19:36:47   2.5N   59.5W mb=4.3  EMSC   GUYANA

O: 31JAN2021 19:48:47   2.5N   59.5W mb=3.8  EMSC   GUYANA

O: 31JAN2021 20:03:45   2.5N   59.5W mb=4.3  EMSC   GUYANA

O: 31JAN2021 19:05:15   2.7N   59.7W Mw=5.7  EMSC   GUYANA

O: 31JAN2021 19:20:40   2.5N   59.5W ML=3.4  EMSC   GUYANA                       

P:  2FEB2021 130819     2.0N   60.0W 4.0-5.4 AAAAA  Guyana                     

 

An M 4.4 earthquake at the antipode of the Guyana M 5.7 occurred several hours earlier today in the area of Majene, Sulawesi, Selatan, Indonesia with intensity IV. Note the antipodal nature of these two epicenters (3N vs 3S and 122E vs 59W). Epicenters are exactly antipodal when the signed latitudes add to zero (the same in both north and south latitudes) and the unsigned longitudes add to 180. Forecasts 130849 and 130539 had expected this activity in Sulawesi, Indonesia at the end of January or early February.  This epicenter is located at the third node (120 degrees) from the South Shetland

 Islands event of January 23 and may have been promoted by energy from that source.

 

O: 31JAN2021 09:29:16   3.0S  122.3E ML=3.7  EMSC   SULAWESI, INDONESIA

O: 31JAN2021 12:13:10   3.0S  119.0E mb=4.4  EMSC   SULAWESI, INDONESIA          

P:  3FEB2021 130849     4.0S  123.0E 4.0-5.8 BACAA  Sulawesi area              

P: 31JAN2021 130539     0.0N  120.0E 4.0-5.6 ACAAA  Celebes Sea                

 

Three moderate earthquakes of M 4.8 were felt in Turkey today. These were reported by NEIC to have been felt with intensity II-III in Izmir, Turkey at Dikili, Karaburun, Izmir, Menderes, and in Ipsala Edirne and Silivri, Istanbul and in Greece at Marmarn, Khios, Hios. These are the strongest earthquakes within about 100 km of these epicenters since an M 6.3 on June 12, 2017 and an aftershock on June 17, 2017 of M 5.2. An M 7.0 hit the area about 150 km southeast of this epicenter on October 30, 2020. Forecast 130904 had expected today's activity was likely around February 3, 2021. This epicenter is located at the third node (120 degrees) from the South Shetland Islands event of January 23 and may have been promoted by energy from that source.

 

O: 01FEB2021 05:03:24  39.0N   26.1E ML=3.9  EMSC   NEAR THE COAST OF WESTERN TURKEY

O: 01FEB2021 05:46:52  39.0N   26.1E mb=4.8  EMSC   NEAR THE COAST OF WESTERN TURKEY

O: 01FEB2021 05:47:53  39.0N   26.0E Mw=4.8  EMSC   NEAR THE COAST OF WESTERN TURKEY

O: 01FEB2021 06:00:05  39.0N   26.1E ML=4.8  EMSC   NEAR THE COAST OF WESTERN TURKEY

O:  1FEB2021 06:34:11  38.9N   26.1E ML=4.0  EMSC   NEAR THE COAST OF WESTERN TURK

P:  3FEB2021 130904    38.0N   26.0E 3.0-4.6 AAAAA  Aegean Sea                 

 

A strong swarm occurred today in the Canary Islands of Spain today. This followed the M 4.7 in the Madeira Islands yesterday and had been anticipated in this summary in the previous issue as:

 

An M 4.7 occurred in the Madeira Islands, Portugal today. This follows a similar event in the area on January 1, 2021. That event was followed by a series in the Canary Islands of Spain to the south of the Madeira Islands. At the time this summary noted:

 

"An unusually large earthquake of M 4.7 shook the Madeira Islands of Portugal today. The last earthquake of M>=4.7 in the Madeira Islands area within about 250 km of today's event was an M 5.2 on March 7, 2020, the only such event in the area in the past 30 years. Forecast 129667 had expected regional activity around January 1 in the Canary Islands about 400 km to the south  of today's epicenter. That region also continued active and may in preparatory stages for an eruption of Tenirefe Volcano." (January 31, 2021)

 

Following is a listing of events of M>2.0 in the Canary Islands today. A more extensive listing can be found in the regional "EUROPE" section of this summary.

 

Forecast 130602 had expected today's activity was likely in the Canary Islands  around January 31. This activity is at the fourth node (90 degrees) from  the M 7.6 in the Alaska Peninsula of October 19, 2020 and was probably promoted by energy from that source.

 

O: 31JAN2021 16:25:18  28.5N   17.9W ML=2.4  EMSC   CANARY ISLANDS, SPAIN REGION

O: 31JAN2021 13:21:23  28.6N   17.8W ML=2.2  EMSC   CANARY ISLANDS, SPAIN REGION

O: 31JAN2021 14:00:51  28.6N   17.8W ML=2.5  EMSC   CANARY ISLANDS, SPAIN REGION

O: 31JAN2021 15:45:50  28.6N   17.9W ML=2.2  EMSC   CANARY ISLANDS, SPAIN REGION

O: 31JAN2021 08:54:53  28.5N   17.9W ML=2.3  EMSC   CANARY ISLANDS, SPAIN REGION 

P: 31JAN2021 130602    28.0N   16.0W 3.0-4.6 AAAAA  Canary Islands             

 

The swarm in the region of Granada, Spain also continued at renewed intensity today. Forecast 130926 had expected this swarm would continue in early February.

 

O: 31JAN2021 13:53:23  37.2N    3.8W ML=3.0  EMSC   SPAIN

O: 31JAN2021 16:21:37  37.2N    3.7W ML=2.0  EMSC   SPAIN

O: 31JAN2021 17:43:52  37.2N    3.7W ML=2.5  EMSC   SPAIN

O: 31JAN2021 23:00:21  37.2N    3.7W ML=2.5  EMSC   SPAIN

O: 31JAN2021 19:02:16  37.1N    2.6W ML=3.3  EMSC   SPAIN                        

O: 31JAN2021 09:41:45  37.2N    3.7W ML=2.5  EMSC   SPAIN                        

P:  4FEB2021 130926    37.0N    3.0W 3.5-5.1 BAAAA  Morocco/Spain              

 

The swarm of earthquakes in southern California today continued. The largest of these was an M 3.3 and was accompanied by a series of a dozen events of events of M>=2. Forecast 130948 had expected today's activity was likely around February 2.

 

O: 01FEB2021 04:18:47  32.8N  115.8W ML=3.3  EMSC   SOUTHERN CALIFORNIA

O: 01FEB2021 04:48:52  32.8N  115.8W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 01FEB2021 00:17:39  33.2N  115.6W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 01FEB2021 04:42:15  33.2N  115.6W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 31JAN2021 20:42:00  33.2N  115.6W ML=2.5  EMSC   SOUTHERN CALIFORNIA

O: 31JAN2021 20:43:29  33.2N  115.7W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 31JAN2021 11:44:58  33.5N  116.5W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O:  1FEB2021 04:23:23  32.6N  115.7W ML=2.3  EMSC   BAJA CALIFORNIA, MEXICO      

O:  1FEB2021 00:12:39  33.2N  115.7W ML=2.6  EMSC   SOUTHERN CALIFORNIA          

P:  2FEB2021 130948    32.4N  115.8W 2.5-4.5 AAAAA  So. California             

 

AUSTRALIA M 5.6; MADEIRA ISLANDS M 4.7 COULD SIGNAL FURTHER ACTIVITY

 

EARTHQUAKE SUMMARY FOR JANUARY 30, 2021

 

An M 4.7 occurred in the Madeira Islands, Portugal today. This follows a similar

event in the area on January 1, 2021. That event was followed by a series in

the Canary Islands of Spain to the south of the Madeira Islands. At the time

this summary noted:

 

"An unusually large earthquake of M 4.7 shook the Madeira Islands of Portugal today. The last earthquake of M>=4.7 in the Madeira Islands area within about 250 km of today's event was an M 5.2 on March 7, 2020, the only such event in the area in the past 30 years. Forecast 129667 had expected regional activity around January 1 in the Canary Islands about 400 km to the south  of today's epicenter. That region also continued active and may in preparatory stages for an eruption of Tenirefe Volcano. Earthquakes of M>=4.7 in the Canary Islands in the past 30 years included an M 5.4 on December 28, 2013 and M 4.7's on March 29, 2013, November 8, 2008 and March 21, 1991." (January 2, 2021)

 

Today's activity follows a major swarm in the Granada, Spain region over the past four days. That swarm saw only minor events today and may be dying out. The M 4.7 in the Madeira Islands occurred within about an hour of local solar noon and may have been enhanced by tidal stresses of the full moon which maximize near this hour. Forecast 130602 had expected the area would be activity with a moderate quake of M 4.6 around January 31. This activity is at 100 degrees from the South Shetland Islands and may have been promoted by concentrated energy from the M 7.1 which occurred there on January 23.

 

O: 30JAN2021 11:15:10  32.0N   16.5W mb=4.7  EMSC   MADEIRA ISLANDS, PORTUGAL REGI

O: 30JAN2021 14:46:53  28.0N   16.2W ML=2.1  EMSC   CANARY ISLANDS, SPAIN REGION 

P: 31JAN2021 130602    28.0N   16.0W 3.0-4.6 AAAAA  Canary Islands             

 

This summary commented on the highly unusual M 5.6 north of Western Australia yesterday as:

 

"An earthquake of M 5.6 also hit northwest of Australia today. NEIC reported it was felt with intensity VI in Broome Western Australia. As noted in the previous issues of this summary this area has seen enhanced seismicity in the past week related to landfall of Tropical Storm 14S in late January, 2021. This summary had noted this is the previous issue as:

 

The last earthquake within about 250 km of this epicenter of larger magnitude was an  M 5.7-5.8 in the Flores area on April 19, 2013. Other events in the region in the past 30 years with M>=5.6 occurred on February 12, 1996 (M 6.1) and April 29, 2006 (M 5.7) in the region of Sumbawa, Indonesia. This is the farthest to the south by at least 200 km of any such event in the past 30 years. Forecast 130764 had expected an M 5.6 quake was likely northeast of this epicenter

in the Flores Island area around January 30.

 

"The strongest earthquake in the world today was an M 5.4 in the Virgin Islands. NEIC reported maximum intensity IV in the British Virgin Islands at Road Town and II-III in the U.S. Virgin Islands at Saint John, Saint Thomas and Frederiksted. It was also felt in the Netherlands Antilles at Low Lands, Simpson ay, Cul De Sac; in Anguilla at the Valley, the Farrington and in Marigot, Saint Martin, Guadeloupe.

This is the strongest earthquake in the Virgin Islands within about 200 km of this epicenter since an M 6.1 on October 11, 2008. This summary previous suggested the area was likely to see enhanced seismicity at this time due to  it's antipodal position from the land fall of Tropical Cyclone 14S on the coast of Northwestern Australia as:

 

 

"A strong swarm of minor earthquakes was felt in the Dominican Republic today. This contained at least a dozen event of M>=3. It may be related to the landfall of Tropical Storm 14S at the antipode in western Australia today as noted in this and previous summaries:

 

"Tropical cyclone 14S formed north of western Australia today with winds up to 50 kts. It is expected to make landfall today south of Broome, Australia. Some seismicity at the antipode near the Virgin Islands, Puerto Rico and the Dominican Republic, Caribbean may be triggered by antipodal energy concentration from this storm." (January 21, 25, 2021)

 

Further activity in this region related to this Tropical Cyclone is to be expected in the next several days." (January 28-29, 2021)

 

A second Tropical Cyclone in this area formed today January 29 as noted in this summary:

 

"A tropical Cyclone may be forming over northwestern Australia. This system is currently located at 18S 124E with winds up to 30 kts. and moving WSW over Australia. Some seismic enhancement may occur as this storm moves through the area." (January 29, 2021)

 

This may have helped promote the M 5.6 earthquake north of this storm.

 

This epicenter is located at 104 degrees from the M 7.1 in the South Shetland Islands of January 23, 2021. Energy from large earthquakes is concentrated at the surface at this distance and can help promote enhanced seismicity following those events, as was probably the case here." (January 29-30, 2021)

 

O: 29JAN2021 19:47:55  14.0S  121.9E Mw=5.6  EMSC   NORTHWEST OF AUSTRALIA       

P: 30JAN2021 130764    10.0S  124.0E 4.0-5.6 ACBAA  Flores Island area         

 

It was not pointed out that the largest earthquake in South America yesterday occurred as an M 4.7 in central Venezuela. This may have been promoted by antipodal focusing of energy from the Australia event. The M 5.6 in Australia, as noted above, combined with antipodal energy from the two Tropical Cyclones  and an M 5.6 in the Flores Sea of January 11 and an M 7.0 in southern Mindanao may have contributed additional antipodal energy to help activate the region of northern South America and the southern Windward Islands in the Caribbean which sees most of the regional activity in Trinidad and Tobago. With the full moon, this regional activation is likely to continue for several more days.

 

 

O: 29JAN2021 19:23:38   7.1N   72.1W mb=4.7  EMSC   APURE, VENEZUELA             

P: 27JAN2021 130543     7.0N   73.0W 4.0-5.5 AAAAA  Colombia                   

 

The strongest earthquake in the U.S. or Canada today was an M 3.5 in western Texas near Odessa. NEIC reported this earthquake of M 3.5 in Western Texas was felt with intensity II-III in the area(s) of  Las Cruces, New Mexico. This follows a series of smaller regional events in earlier January, 2021 but is the strongest event within about 200 km of this epicenter in western Texas since an M 3.9 on October 28, 2020. Forecast 130663 had expected today's activity with the full moon was likely around January 29. Today's activity in the region began with an M 2.6 within about 15 minutes of local solar midnight, a time when tidal stresses are maximized with the full moon. This activity is at 102 degrees from the South Shetland Islands M 7.1 of January 23 and may have been promoted by energy from that source. Similar earthquakes today at this distance from the South Shetland Islands included the M 5.6 north of Australia and an M 3.5 in the Azores. The Madeira Islands area at 100 degrees from the South Shetland Islands.

 

O: 30JAN2021 09:10:29  31.7N  104.4W ML=3.5  EMSC   WESTERN TEXAS

O: 30JAN2021 22:47:39  31.7N  104.4W mb=2.5  EMSC   WESTERN TEXAS

O: 30JAN2021 23:11:46  31.7N  104.4W mb=2.6  EMSC   WESTERN TEXAS

O: 30JAN2021 07:13:45  31.7N  104.4W ML=2.6  EMSC   WESTERN TEXAS                

P: 29JAN2021 130663    31.5N  103.6W 2.0-4.1 AAAAA  SW U.S.A                   

 

A nor’easter is forming in the northeastern U.S. Depending on the motion and strength of this storm, it may resonate with the North American Plate and trigger a moderate to large earthquake in the western edge of the plate. More details as this develops.

 

MODERATE QUAKES IN PANAMA AND COSTA RICA

 

EARTHQUAKE SUMMARY FOR JANUARY 29, 2021

 

Several moderate earthquakes shook the area near the border of Panama and Costa Rica today. An M 5.5 was reported felt with maximum intensity VI in Puerto Armuelles, V in Finca Corredor and David, Chiriqui, Panama. The M 5.5 was an aftershock of an M 5.6 in the same area which NEIC reported was felt with intensity VII in Puerto Armuelles, IV in Los Lomas, and II-III in Panama City, Guarumal, David, Boquette, Chiriqui, Panama and in Costa Rica at Puerto Cortes and Jaco, Puntarenas. These may have been promoted by high tidal stresses associated with the full moon which arrived on January 28 as noted in previous issues of this summary:

 

"The full moon arrived on January 28, 2021 at 19:16 UT. Longitudes which were at sub-solar conditions at this time area near 110 West and 70 East longitude. These include in the West regions of the Rocky Mountains and western North America and in the east Afghanistan and Central Asia. These areas may see enhanced seismicity due to tidal effects over the next week. Seismicity may shift to times closer to local solar noon and midnight during this period, and a moderately large earthquake is possible at this time due to tidal triggering." (January 26-29, 2021)

 

The M 5.6 is the strongest earthquake within about 150 km of these epicenters since an M 5.6 on September 4, 2020 about 25 km north of today's M 5.6. The last of  larger magnitude in this region occurred with M 6.1 and 6.2 on May 12 and June 26, 2019. Forecast 130544 had expected today's activity in this region was likely around January 30. This activity is located at 145-146 degrees from the M 7.0 in Mindanao, Philippines of January 21; at 101 degrees from the M 7.0 in the Dodecanese Islands of October 30, 2020; at the fifth node (72 degrees from the South Shetland Islands M 7.1 of January 23  and at the third node (120 degrees) from the M 6.7 in Mongolia of January 11 and was probably promoted by energy from those sources.

 

O: 29JAN2021 16:44:30   7.7N   82.8W ML=4.3  EMSC   SOUTH OF PANAMA

O: 29JAN2021 11:25:42   7.8N   83.0W ML=4.1  EMSC   SOUTH OF PANAMA

O: 29JAN2021 13:42:30   8.0N   82.9W ML=4.5  EMSC   SOUTH OF PANAMA

O: 29JAN2021 14:10:30   8.0N   82.9W ML=4.0  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 29JAN2021 15:03:30   8.0N   82.9W ML=4.8  EMSC   SOUTH OF PANAMA

O: 29JAN2021 13:08:30   8.1N   82.9W ML=4.2  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 29JAN2021 15:09:30   8.1N   82.9W ML=4.6  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 29JAN2021 12:41:39   8.2N   83.0W Mw=5.6  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 29JAN2021 11:23:28   8.3N   83.0W mb=4.9  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 29JAN2021 13:14:45   8.3N   82.9W Mw=5.5  EMSC   PANAMA-COSTA RICA BORDER REGION

O: 29JAN2021 22:16:30   8.4N   82.9W ML=4.0  EMSC   PANAMA-COSTA RICA BORDER REGIO

P: 30JAN2021 130544     8.0N   82.0W 3.5-5.1 AAAAA  Costa Rica                 

 

An earthquake of M 5.6 also hit northwest of Australia today. NEIC reported it was felt with intensity VI in Broome Western Australia. As noted in the previous issues of this summary this area has seen enhanced seismicity in the past week related to landfall of Tropical Storm 14S in late January, 2021. This had been noted in this summary as:

 

"Tropical cyclone 14S formed north of western Australia today with winds up to 50 kts. It is expected to make landfall today south of Broome, Australia. Some seismicity at the antipode near the Virgin Islands, Puerto Rico and the Dominican Republic, Caribbean may be triggered by antipodal energy concentration from this storm." (January 21, 25, 2021)

 

Further activity in this region related to this Tropical Cyclone is to be

expected in the next several days." (January 28-29, 2021)

 

A second Tropical Cyclone in this area formed today January 29 as noted in this summary:

 

"A tropical Cyclone may be forming over northwestern Australia. This system is currently located at 18S 124E with winds up to 30 kts. and moving WSW over Australia. Some seismic enhancement may occur as this storm moves through the area." (January 29, 2021)

 

This may have helped promote the M 5.6 earthquake north of this storm.

 

 

The last earthquake within about 250 km of this epicenter of larger magnitude was an M 5.7-5.8 in the Flores area on April 19, 2013. Other events in the region in the past 30 years with M>=5.6 occurred on February 12, 1996 (M 6.1) and April 29, 2006 (M 5.7) in the region of Sumbawa, Indonesia. This is the farthest to the south by at least 200 km of any such event in the past 30 years. Forecast 130764 had expected an M 5.6 quake was likely northeast of this epicenter in the Flores Island area around January 30.

 

This epicenter is located at 104 degrees from the M 7.1 in the South Shetland

Islands of January 23, 2021. Energy from large earthquakes is concentrated at the surface at this distance and can help promote enhanced seismicity following those events, as was probably the case here.

 

O: 29JAN2021 19:47:55  14.0S  121.9E Mw=5.6  EMSC   NORTHWEST OF AUSTRALIA       

P: 30JAN2021 130764    10.0S  124.0E 4.0-5.6 ACBAA  Flores Island area         

 

The strongest earthquake in the U.S., Canada or vicinity today was an M 3.7 in northern Baja California. It was not reported felt in this remote area but is an unusual event. It is the strongest quake within about 125 km of this epicenter since September 15, 2010 and the strongest within about 100 km since an M 4.9 and 5.1 on May 1, 2006 and a similar pair on February 19, 2008. An M 7.0 shook the region about 100 km to the east of this on April 12, 2012. Forecast 130662 expected today's activity within about 150 km was likely to the north around January 30.

 

This epicenter is located at 102 degrees from the M 7.1 in the South Shetland

Islands of January 23, 2021. Energy from large earthquakes is concentrated at the surface at this distance and can help promote enhanced seismicity following those events, as was probably the case here.

 

O: 29JAN2021 09:27:20  28.9N  114.3W ML=3.7  EMSC   BAJA CALIFORNIA, MEXICO      

P: 30JAN2021 130662    30.2N  114.1W 2.0-4.1 ABAAA  SW U.S.A                   

 

MODERATE QUAKES SHAKE TAIWAN

 

EARTHQUAKE SUMMARY FOR JANUARY 28, 2021

 

The strongest earthquake in the world today was an M 5.0 in the region of Taiwan. It was followed by an M 4.0 aftershocks. This follows moderate quakes over the past several days in the southwestern Ryukyu  Islands northeast of Taiwan. CWB reported this earthquake of M 5.0 was felt with intensity IV in Taitung, II in Chiayi and Pingtung and I in Tainan, Chiayi, Yunlin, Nantou and Changhua Counties, Taiwan. The M 4.0 was felt with intensity IV in Taitung and I in Pingtung. Forecasts 130617 and 130618 had expected today's activity was likely at the end of January. This activity is located at 141 degrees from the South Shetland Islands M 7.1 of January 23 and may have been promoted by energy from that source.

 

O: 28JAN2021 07:29:32  22.6N  121.0E mb=4.8  EMSC   TAIWAN REGION

O: 28JAN2021 08:05:04  22.5N  121.0E ML=4.1  EMSC   TAIWAN                       

O: 28JAN2021 07:29:31  22.5N  121.0E ML=5.0  TAI    Hualien, Taiwan              

O: 28JAN2021 08:05:04  22.5N  121.0E ML=4.1  TAI    Hualien, Taiwan              

P: 25JAN2021 130617    23.0N  121.0E 4.0-5.4 BAAAA  Taiwan                     

P: 30JAN2021 130618    24.0N  122.0E 4.0-5.5 ABAAA  Taiwan                     

 

The strong swarm of earthquakes in the area of Granada, Spain continued today. The strongest of the day was an M 4.3 felt with intensity IV in Granada, Spain.

This summary noted regarding this swarm in previous issues:

 

 

"The series of moderate earthquakes in Granada, Southern Spain continued today. The largest of these today was an M 4.4 felt with maximum intensity VI in Granada at Atarfe, Maracena; V in Albolote, IV in Pulianas, Granada, Pinos Genil and Lanjaron, and III in Armilla, Cenes de la Vega, and Almunecar. This is the most active the area has been since an M 4.4 occurred on January 23.

The M 4.4 events are the strongest in Spain in at least a year. The last earthquake of M>=4.4 in the Granada, Spain area occurred on January 31, 2012 with M 4.4. The last of larger magnitude was an M 4.5 on November 16, 2003. Forecast 130640 had expected activity in this area in late January, 2021." (January 26-27, 2021)

 

O: 28JAN2021 18:49:48  37.2N    3.7W ML=4.3  EMSC   SPAIN

O: 28JAN2021 18:06:28  37.2N    3.7W ML=3.6  EMSC   SPAIN                        

P: 29JAN2021 130648    37.0N    6.0W 3.5-5.3 AABAA  Morocco/Spain              

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the Alaska Peninsula southeast of the aftershock zone of the M 7.6 of October 19, 2020. This is the strongest earthquake within about 150 km of this epicenter since an M 4.5 on July 1, 2018. Forecast 130749 had expected regional seismicity at the end of January. Like the activity in Taiwan today, this event is located at 144 degrees from the M 7.1 in the South Shetland Islands of January 23, 2021. It, along with other activity in Alaska today was probably enhanced by seismic energy from that source.

 

O: 29JAN2021 06:33:26  58.4N  156.8W mb=4.4  EMSC   ALASKA PENINSULA              

P: 23JAN2021 130749    60.2N  151.7W 3.2-5.0 CBCCA  Central Alaska             

 

A light earthquake of M 3.2 continued elevated seismicity in Western Australia which followed landfall of TC 14S in the area in late January, 2021. This was noted in regard to enhanced seismicity at the antipode in the northeastern

Caribbean, especially in the Virgin Islands area as:

 

 

"The strongest earthquake in the world today was an M 5.4 in the Virgin Islands. NEIC reported maximum intensity IV in the British Virgin Islands at Road Town and II-III in the U.S. Virgin Islands at Saint John, Saint Thomas and Frederiksted. It was also felt in the Netherlands Antilles at Low Lands, Simpson ay, Cul De Sac; in Anguilla at the Valley, the Farrington and in Marigot, Saint Martin, Guadeloupe. This is the strongest earthquake in the Virgin Islands within about 200 km of this epicenter since an M 6.1 on October 11, 2008. This summary previous suggested the area was likely to see enhanced seismicity at this time due to it's antipodal position from the land fall of Tropical Cyclone 14S on the coast of Northwestern Australia as:

 

 

"A strong swarm of minor earthquakes was felt in the Dominican Republic today. This contained at least a dozen event of M>=3. It may be related to the landfall of Tropical Storm 14S at the antipode in western Australia today as noted in this and previous summaries:

 

"Tropical cyclone 14S formed north of western Australia today with winds up to 50 kts. It is expected to make landfall today south of Broome, Australia. Some seismicity at the antipode near the Virgin Islands, Puerto Rico and the Dominican Republic, Caribbean may be triggered by antipodal energy concentration from this storm." (January 21, 25, 2021)

 

Further activity in this region of Australia related to this Tropical Cyclone is to be expected in the next several days.

 

O: 28JAN2021 23:53:20  18.4S  120.4E ML=3.2  EMSC   WESTERN AUSTRALIA            

 

MODERATE QUAKE SHAKES COAST OF NORTHERN CALIFORNIA

 

EARTHQUAKE SUMMARY FOR JANUARY 27, 2021

 

The strongest earthquake in the U.S. or Canada and the strongest felt earthquake in the world today was an M 4.6 off the coast of Northern California. NEIC reported it was widely felt on the California coast with light intensity at Arcata, Point Arena, San Francisco, Martinez, Citrus Heights and Redwood City, California and in Coos Bay and Ashland, Oregon. This is the strongest earthquake within about 100 km of this epicenter off the coast of Northern California since an M 5.5 on May 28, 2020. That event was preceded by a foreshock of M 4.7. This event is probably related to the current activation of California and was expected in this summary in the previous issue at this time as:

 

"The seismic watch for California which followed the M 7.1 in the South Shetland Islands of January 23, 2021 is being modified. As a number of light earthquakes have occurred in the watch area since that time including a swarm near the Baja and Southern California, several in the San Fernando Valley and others in eastern Los Angeles and today's in the Santa Catalina Islands area south of Los Angeles, triggering does appear to be occurring from the South Shetland area. But none of these have been large enough to warrant the expectation of a large event in the next several days. California, however, will remain in a precautionary state of elevated seismic risk associated with this, the largest geomagnetic storm in two month, and the full moon for the next five days. A moderate earthquake of M>=4 is expected in this region in this period." (January 26-27, 2021)

 

Forecast 130712 had expected today's event to the north of this was likely

around January 26.

 

O: 27JAN2021 16:25:16  40.4N  127.1W Mw=4.6  EMSC   OFF COAST OF NORTHERN CALIFORN

P: 26JAN2021 130712    42.5N  126.8W 3.0-4.5 ABAAA  Off Coast of Oregon        

 

The current swarm on the California-Baja California border continued today with a series of more than 6 events of M>=2, the largest of which was an M 2.5. These area located near 103 degrees from the South Shetland Islands M 7.1 of January 23 and may have been promoted by energy from that source. Forecast 130666 had expected today's activity was likely around January 25.

 

O: 27JAN2021 09:01:12  32.7N  115.8W ML=2.0  EMSC   SOUTHERN CALIFORNIA

O: 27JAN2021 20:50:59  32.8N  115.8W ML=2.1  EMSC   SOUTHERN CALIFORNIA

O: 28JAN2021 05:30:52  33.2N  115.6W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 28JAN2021 05:40:34  33.2N  115.6W ML=2.5  EMSC   SOUTHERN CALIFORNIA

O: 28JAN2021 06:26:58  33.2N  115.6W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 27JAN2021 11:29:11  32.4N  115.2W Ml=2.1  EMSC   BAJA CALIFORNIA, MEXICO      

P: 25JAN2021 130666    32.6N  116.1W 2.5-4.6 AAAAA  So. California             

 

It was a relatively quiet day in global seismicity. The largest earthquakes in the world, both of M 5.0, occurred in the Southwest Pacific and were not reported felt. Forecast 130774 had expected activity in this area at the end of January.

 

O: 27JAN2021 09:10:39  20.3S  178.1W mb=5.0  EMSC   FIJI REGION                  

P: 26JAN2021 130774    18.0S  180.0W 4.0-5.8 ACBAA  Tonga Islands              

 

The other event of M 5.0 in the Bougainville Region, PNG, followed larger earthquakes in the area over the last several days. This summary noted this activity in the previous issue as:

 

 

"A similar earthquake in the Bougainville Region of PNG occurred on January 6, 2021 with M 5.8 and prior to that an M 5.5 on November 16, 2020. Today's event was probably an aftershock of those earlier events. Forecast 130570 had exepcted today's event was likely within about 100 km around January 24." (January 25-26, 2021)

 

O: 28JAN2021 06:03:21   6.4S  154.1E mb=5.0  EMSC   BOUGAINVILLE REGION, P.N.G.  

P: 26JAN2021 130559     6.0S  154.0E 4.0-5.4 AAAAA  New Britain                

 

MODERATE QUAKES IN HOKKAIDO; GRANADA, SPAIN

 

EARTHQUAKE SUMMARY FOR JANUARY 26, 2021

 

The largest earthquake in the world today was an M 5.2 in Hokkaido Japan.

NEIC reported this earthquake of M 5.2 in Hokkaido, Japan was felt with intensity II-III in the area(s) of Hokkaido, Japan in Shizunai, Sapporo and Otofuke and in Aomori. This is the largest event in Hokkaido since an M 6.0 on January 12, 2021 about 250 km northwest of today's epicenter. The last event of larger or similar activity in Hokkaido within about 200 km of this epicenter was an M 5.3 on December 16, 2020. Forecast 130695 expected today's event within about 100 km was likely around January 26.

 

O: 27JAN2021 05:06:52  42.8N  142.0E Mw=5.2  EMSC   HOKKAIDO, JAPAN REGION       

P: 26JAN2021 130695    42.0N  142.0E 3.5-5.8 AAAAA  Hokkaido, Japan            

 

The series of moderate earthquakes in Granada, Southern Spain continued today. The largest of these today was an M 4.4 felt with maximum intensity VI in Granada at Atarfe, Maracena; V in Albolote, IV in Pulianas, Granada, Pinos Genil and Lanjaron, and III in Armilla, Cenes de la Vega, and Almunecar. This is the most active the area has been since an M 4.4 occurred on January 23. The M 4.4 events are the strongest in Spain in at least a year. The last earthquake of M>=4.4 in the Granada, Spain area occurred on January 31, 2012 with M 4.4. The last of larger magnitude was an M 4.5 on November 16, 2003. Forecast 130640 had expected activity in this area in late January, 2021.

 

 

O: 26JAN2021 21:44:17  37.2N    3.7W ML=4.2  EMSC   SPAIN

O: 26JAN2021 21:54:54  37.2N    3.7W mb=4.4  EMSC   SPAIN

O: 26JAN2021 22:00:00  37.2N    3.7W ML=3.5  EMSC   SPAIN

O: 26JAN2021 21:36:32  37.2N    3.7W ML=4.1  EMSC   SPAIN                        

P: 29JAN2021 130648    37.0N    6.0W 3.5-5.3 BABAA  Morocco/Spain              

 

Other light to moderate earthquakes in Europe today occurred as an M 3.0 in Austria, Syria (M 4.4, 4.9); Albania (M 3.8) and Macedonia (M 3.4).

 

NEIC reported the earthquake of M 4.9 in Syria was felt with intensity II-III in the area(s) of Turkey at Kizitepe, Mardin.  Forecast 130684 had expected this activity was likely around January 27.

 

O: 26JAN2021 11:17:42  36.2N   41.3E mb=4.9  EMSC   SYRIA-IRAQ BORDER REGION

O: 26JAN2021 10:02:11  36.2N   41.2E ML=4.4  EMSC   SYRIA-IRAQ BORDER REGION     

P: 27JAN2021 130684    38.0N   43.0E 3.5-4.9 ABBAA  Turkey                     

 

NEIC reported the earthquake of M 4.5 in Albania was felt with intensity II-III in the area(s) of Albania at Mamurras Kruje. Forecast 130717 had expected today's activity was likely around January 25.

 

O: 26JAN2021 14:32:44  41.6N   19.5E ML=3.8  EMSC   ALBANIA                      

O: 26JAN2021 14:32:44  41.6N   19.5E ML=4.5  ANSS   ALBANIA                      

P: 25JAN2021 130717    41.0N   20.0E 3.0-5.5 AAAAA  Romania/NW Turkey          

 

O: 27JAN2021 00:44:00  47.4N   15.0E ML=3.0  EMSC   AUSTRIA                      

P: 29JAN2021 130689    46.0N   14.0E 3.0-5.6 ABAAA  Austria                    

 

O: 27JAN2021 06:44:08  41.7N   20.8E ML=3.4  EMSC   REPUBLIC OF NORTH MACEDONIA  

P: 25JAN2021 130717    41.0N   20.0E 3.0-5.5 AAAAA  Romania/NW Turkey          

 

The strongest seismicity in California today occurred in the islands off the southern coast of Los Angeles. The strongest of these was an M 2.9-3.0 in the Gulf of Santa Catalina where an aftershock of M 2.1 also occurred. An M 2.4 was recorded after this in the San Pedro Channel south of Los Angeles. The M 3.0 in the Gulf of Catalina was the strongest in that region since an M 3.2 on November 21, 2019. These may be related to triggering from the M 7.1 of January 23, 2021 which was expected to enhance seismicity in this area at this time due to its distance from the area. Forecast 130669 had expected today's event was likely within about 50 km of this epicenter around January 26.

 

NEIC reported the earthquake of M 3.1 in the Gulf of Santa Catalina, California  was felt with intensity II-III in the area(s) of  the Gulf of Santa Catalina, California at Carlsbad, Oceanside, Encinitas, San Clemente, Vista, Escondido, San Diego, Aliso Viejo and Temecula.

 

O: 26JAN2021 07:48:46  33.1N  117.6W ML=2.9  EMSC   GULF OF SANTA CATALINA, CALIF.

O: 26JAN2021 08:11:23  33.1N  117.6W Ml=2.1  EMSC   GULF OF SANTA CATALINA, CALIF.

P: 26JAN2021 130669    33.7N  117.5W 2.5-4.5 AAAAA  So. California             

 

The last earthquake of M>3in the San Pedro Channel of California was an M 3.2 on

December 7, 2019. Forecast 130667 had expected this area would be active within about 25 km around January 25.

 

O: 26JAN2021 15:16:31  33.5N  118.3W Ml=2.4  EMSC   SAN PEDRO CHANNEL, CALIFORNIA

P: 25JAN2021 130667    33.6N  118.5W 2.5-4.6 AAAAA  So. California             

 

The seismic watch for California which followed the M 7.1 in the South Shetland Islands of January 23, 2021 is being modified. As a number of light earthquakes have occurred in the watch area since that time including a swarm near the Baja and Southern California, several in the San Fernando Valley and others in eastern Los Angeles and today's in the Santa Catalina Islands area south of Los Angeles, triggering does appear to be occurring from the South Shetland area. But none of these have been large enough to warrant the expectation of a large event in the next several days. California, however, will remain in a precautionary state of elevated seismic risk associated with this, the largest geomagnetic storm in two month, and the full moon for the next five days. A moderate earthquake of M>=4 is expected in this region in this period.

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the Kenai Peninsula of Alaska. This event occurred within about 30 minutes of local solar noon and was probably promoted by strong tidal stresses associated with the full moon of January 18. It is the strongest earthquake recorded in the Kenai Peninsula in the past year. The last such event of larger magnitude was an M 4.5 on December 1, 2019. An M 5.8 shook the area on May 27, 2019. Forecast 130751 had expected today's activity was likely at the end of January.

 

NEIC reported this earthquake of M 4.3-4.4 in Kenai Peninsula, Alaska was felt with intensity II-III in the area(s) of Kenai Peninsula, Alaska at Homer, Anchor Point and Anchorage. This epicenter is at 142 degrees from the M 7.1 in the South Shetland Islands of January 23 and may have been promoted by energy from that source.

 

O: 26JAN2021 22:23:24  59.2N  151.7W mb=4.4  EMSC   KENAI PENINSULA, ALASKA      

P: 29JAN2021 130751    61.3N  152.3W 3.2-5.1 BBAAA  Central Alaska             

 

MODERATE QUAKES IN NEW GUINEA; RYUKYU ISLANDS

 

EARTHQUAKE SUMMARY FOR JANUARY 25, 2021

 

The largest earthquakes in the world today occurred with magnitudes in the lower 5's. The largest of these was an M 5.4 in the Bougainville Region, Papua New Guinea and an M 5.2 and an M 5.1 in New Britain, PNG and M 5.2 northeast of Taiwan in the region of the Ryukyu Islands, Japan.

 

A similar earthquake in the Bougainville Region of PNG occurred on January 6, 2021 with M 5.8 and prior to that an M 5.5 on November 16, 2020. Today's event was probably an aftershock of those earlier events. Forecast 130570 had exepcted today's event was likely within about 100 km around January 24.

 

O: 26JAN2021 04:17:57   7.0S  155.8E Mw=5.4  EMSC   BOUGAINVILLE REGION, P.N.G.  

P: 24JAN2021 130570     8.0S  156.0E 4.0-5.4 AAAAA  Solomon Islands            

 

The M 5.2 in New Britain follows a similar M 5.2 on January 2, 2021 and an M 5.4 on December 27, 2020. Forecast 130559 had expected this activity within about 50 km at the end of January.

 

NEIC reported this earthquake of M 5.2 in New Britain, PNG was felt with intensity II-III in the area(s) of New Britain, PNG at Kokopo New Britain.  This activity is located at the third node from the Dodecanese Islands M 7.0 of October 30, 2020 and may have been promoted by energy from that source.

 

O: 25JAN2021 07:53:22   4.6S  152.2E Mw=5.2  EMSC   NEW BRITAIN REGION, P.N.G.   

O: 25JAN2021 21:26:13   5.6S  151.9E mb=5.1  EMSC   NEW BRITAIN REGION, P.N.G.   

P: 29JAN2021 130559     5.0S  152.0E 4.0-5.4 BAAAA  New Britain                

 

A series of moderate sized earthquakes which occurred in the Southwestern Ryukyu

Islands of Japan today were felt in Taiwan. The strongest of these was an M 5.2 but others of M 4.9 and 4.4 also occurred. CWB reported this earthquake of M 4.8 was felt with intensity III in Yilan, II in Taipei and Hualien and I in Taoyuan, Hsinchu, Taichung, Nantou, Miaoli, Changhua and Taitung Counties, Taiwan.

CWB reported the earthquakes of M 5.2 and 4.8 were felt with intensity III in Taitung, II in Changhua and I in Hualien, Yilan, Nantou, Taichung, Yunlin, Miaoli and Hsinchu Counties, Taiwan. NEIC reported this earthquake of M 5.2 in the Southwest Ryukyu Islands, Japan was felt with intensity II-III in the area(s) of the Southwest Ryukyu Islands, Japan in Taichung, Taiwan. The M 5.2 in the Ryukyu Islands is the strongest within about 150 km of this epicenter since an M 5.3 on March 30, 2020. Forecast 130619 had expected today's activity within about 100 km was likely around January 27. This activity in the Ryukyu Islands is located at 142-143 degrees from the M 7.1 in the South Shetland Islands of January 23 and was probably promoted by energy from  that source. The largest earthquake in the U.S. - an M 4.9 in southern Alaska occurred at this same distance from the South Shetland Islands.

 

 

O: 25JAN2021 11:39:23  24.8N  122.2E ML=4.8  TAI    Hualien, Taiwan              

O: 25JAN2021 07:25:37  23.3N  123.4E ML=5.2  TAI    Hualien, Taiwan              

O: 25JAN2021 09:05:57  23.3N  123.4E ML=4,8  TAI    Hualien, Taiwan              

O: 25JAN2021 07:25:36  23.6N  123.6E Mw=5.2  EMSC   SOUTHWESTERN RYUKYU ISL., JAPAN

O: 25JAN2021 11:39:23  24.8N  122.2E mb=4.4  EMSC   TAIWAN REGION

O: 25JAN2021 09:05:54  23.5N  123.7E Mw=4.9  EMSC   SOUTHWESTERN RYUKYU ISL., JAPA

P: 27JAN2021 130619    24.0N  123.0E 4.0-5.6 AAAAA  Taiwan                     

 

The earthquake swarm in southern Spain continued today with a number of light earthquakes, the largest of which was M 3.3. In the previous issue of this summary it had been noted:

 

"NEIC reported this earthquake of M 4.3 in Granada, Spain was felt with intensity II-III in the area(s) of Granada, Spain in Armilla and Granada (IV) and in Talvera de la Reina, Toledo." (January 24-25, 2021)

 

Forecast 130648 had expected this activity at the end of January, 2021. This series is expected to expand and increase in magnitude in the next several days. This activity is located at 102 degrees from the Los Lagos M 6.7 of December 27, 2020 and may have been promoted by energy from that source.

 

O: 25JAN2021 09:09:42  37.2N    3.7W ML=3.3  EMSC   SPAIN                        

P: 29JAN2021 130648    37.0N    6.0W 3.5-5.3 BABAA  Morocco/Spain              

 

The largest earthquakes in the U.S. or Canada today were an M 4.9 in the Rat Island, which was unfelt, and an M 4.9 in southern Alaska. NEIC reported the event in Southern Alaska was felt with intensity II-III in Alaska at Valdez, Seward, Anchorage, Chugiak and Homer. The last earthquake of M>=4.9 in the Rat Islands, Aleutians was an M 4.9 on September 24, 2020. The only event of larger magnitude in the Rat Islands in the past year was an M 5.3 on February 4, 2020. Forecast 130741 had expected today's event was likely in the Rat Islands around January 23.

 

O: 25JAN2021 17:22:37  51.5N  177.8E mb=4.9  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 23JAN2021 130741    50.0N  178.0E 4.0-5.6 ABAAA  Rat Islands                

 

The last earthquake in Southern Alaska with M>=4.9 within about 150 km of today's epicenter in the Kenai Peninsula was an M 5.3 about 150 km to the west on November 27, 2017 and prior to that an M 5.0 on May 2, 2016 about 150 km to the southeast. Forecast 130748 had expected today's activity was likely in this area around January 27.  This activity in Southern Alaska is located at 142-143 degrees from the M 7.1 in the South Shetland Islands of January 23 and was probably promoted by energy from that source.

 

O: 25JAN2021 22:02:00  60.3N  146.0W Mw=4.9  EMSC   SOUTHERN ALASKA              

P: 27JAN2021 130748    61.3N  147.2W 3.2-5.0 AAAAA  Central Alaska             

 

A series of light earthquakes near the Baja-Southern California border area occurred today. The largest of these, and M 2.8, near local solar noon, was probably promoted by high tidal stresses which maximize near this hour. Forecast 130666 had expected today's activity was likely within about 25 km around January 25. This activity is located at 105-106 degrees from the M 7.1 in the South Shetland Islands and was probably promoted by concentrated energy from that source. Other earthquakes today near this distance from the South Shetland Islands occurred today in West Texas, Missouri, and the Santa Cruz Islands north of Vanuatu.

 

O: 25JAN2021 20:52:28  32.7N  115.9W ML=2.8  EMSC   SOUTHERN CALIFORNIA

O: 26JAN2021 04:12:33  32.7N  115.8W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 26JAN2021 04:21:58  32.8N  115.8W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 25JAN2021 21:29:13  33.0N  116.4W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 25JAN2021 08:16:18  33.2N  115.6W ML=2.5  EMSC   SOUTHERN CALIFORNIA

O: 25JAN2021 08:18:28  33.2N  115.6W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 25JAN2021 15:41:10  32.7N  115.8W Ml=2.1  EMSC   SOUTHERN CALIFORNIA          

P: 25JAN2021 130666    32.6N  116.1W 2.5-4.6 AAAAA  So. California             

 

Other activity in Southern California south of Los Angeles today occurred  as an M 2.2 in eastern Los Angeles. Should a larger event occur in the general area of Los Angeles, it could see smaller events in this area and in the area of the Pacific Ocean south of Los Angeles - in the Gulf of Catalina - in the next several days. This is typical of regional events leading to  larger areal events. Forecast 130671 had expected today's activity in  Los Angeles was likely around January 26.

 

O: 25JAN2021 17:35:27  34.3N  117.8W Ml=2.2  EMSC   SOUTHERN CALIFORNIA          

P: 26JAN2021 130671    34.3N  118.5W 2.5-4.5 AAAAA  So. California             

 

MODERATE QUAKE SHAKES VIRGIN ISLANDS

 

EARTHQUAKE SUMMARY FOR JANUARY 24, 2021

 

The strongest earthquake in the world today was an M 5.4 in the Virgin Islands. NEIC reported maximum intensity IV in the British Virgin Islands at Road Town and II-III in the U.S. Virgin Islands at Saint John, Saint Thomas and Frederiksted. It was also felt in the Netherlands Antilles at Low Lands, Simpson ay, Cul De Sac; in Anguilla at the Valley, the Farrington and in Marigot, Saint Martin, Guadeloupe. This is the strongest earthquake in the Virgin Islands within about 200 km of this epicenter since an M 6.1 on October 11, 2008. This summary previous suggested the area was likely to see enhanced seismicity at this time due to it's antipodal position from the land fall of Tropical Cyclone 14S on the coast of Northwestern Australia as:

 

 

"A strong swarm of minor earthquakes was felt in the Dominican Republic today. This contained at least a dozen event of M>=3. It may be related to the landfall of Tropical Storm 14S at the antipode in western Australia today as noted in this and previous summaries:

 

"Tropical cyclone 14S formed north of western Australia today with winds up to 50 kts. It is expected to make landfall today south of Broome, Australia. Some seismicity at the antipode near the Virgin Islands, Puerto Rico and the Dominican Republic, Caribbean may be triggered by antipodal energy concentration from this storm." (January 21, 2021)

 

Forecast 130298 had expected today's activity in the Dominican Republic was likely around January 19. This activity is also at 146 degrees from the M 7.0 in

the Philippines and may have enhanced by energy from that source." (January 21-22, 2021)

 

Forecast 130585 had expected today's event within about 100 km of this epicenter to occur at the end of January.

 

O: 24JAN2021 23:21:41  18.3N   64.1W ml=5.4  ANSS   Bay U.S. Virgin Islands      

P: 28JAN2021 130585    19.0N   64.0W 3.0-5.3 BAAAA  Leeward Islands            

 

A series of moderate earthquakes shook North Island, New Zealand today in the area of Rotorua, a popular region near Lake Taupo. The largest of these was an M 5.2 with NEIC reported was felt with intensity VI in Rotorua and Kawerau and IV in Whakatane with intensity III in the Bay of Plenty area at Murupara, Te Puke, Maketu and Tauranga. An M 4.6 foreshock was reported felt with intensity V in Rotorua, Kawerau and Whakatane. GEONET reported the M 5.0 was felt with moderate intensity northeast of Rotorua and in northwestern North Island. Light to moderate intensity was reported throughout much of northern and western North Island. More than 5235 people reported feeling this earthquake with 2115 reports of weak intensity; 1993 of light intensity; 956 with moderate intensity; 151 with strong intensity; and 14 of severe intensity and 6 of extreme shaking.

The M 4.5 was felt with moderate intensity northeast of Rotorua and in northwestern North Island. Light to moderate intensity was reported throughout much of northern and western North Island. More than 3217 people reported feeling this earthquake with 1269 reports of weak intensity; 1412 of light intensity; 486 with moderate intensity; 46 with strong intensity; and 3 of severe intensity and 1 of extreme shaking. The last earthquake within about 150 km of this epicenter in the Rotorua area with M>5.2 occurred at an intermediate focus on November 23, 2019 with M 5.8. The last shallow focus earthquake in the region with M>=5.2 was an M 5.3 on July 13, 2012. Forecast 130804 had expected this activity was likely around January 23, 2021.

This activity is at the fifth node (72 degrees) from the South Shetland Islands

and may have been promoted by energy from that source.

 

O: 24JAN2021 18:57:01  38.1S  176.5E ML=4.7  EMSC   NORTH ISLAND OF NEW ZEALAND

O: 24JAN2021 19:02:18  38.1S  176.5E ML=3.5  EMSC   NORTH ISLAND OF NEW ZEALAND

O: 24JAN2021 19:16:47  38.1S  176.5E ML=3.8  EMSC   NORTH ISLAND OF NEW ZEALAND

O: 24JAN2021 21:21:03  38.1S  176.5E ML=4.1  EMSC   NORTH ISLAND OF NEW ZEALAND

O: 24JAN2021 21:40:50  38.1S  176.5E ML=3.6  EMSC   NORTH ISLAND OF NEW ZEALAND

O: 25JAN2021 00:48:41  38.1S  176.5E ML=4.0  EMSC    NORTH ISLAND OF NEW ZEALAND

O: 24JAN2021 20:26:32  37.9S  176.8E ML=4.1  EMSC   NORTH ISLAND OF NEW ZEALAND  

O: 24JAN2021 19:12:35  38.2S  176.5E mb=5.2  EMSC   NORTH ISLAND OF NEW ZEALAND  

O: 24JAN2021 19:12:34  38.1S  176.5E ML=5.0  GEONET Felt with moderate intensity

O: 24JAN2021 18:57:02  38.1S  176.5E ML=4.5  GEONET Felt with moderate intensity

P: 23JAN2021 130804    40.0S  176.0E 3.0-4.4 ABAAA  North Island, N.Z.         

 

A moderate M 5.2 also shook areas of Tajikistan and Pakistan today. Maximum intensity V was reported from Tall, North-west Frontier, Pakistan. This is at the longitude of maximum tidal stress with the coming full moon as noted in this summary and may have been promoted by strong tides as:

 

 

"The full moon will arrive on January 28, 2021 at 19:16 UT. Longitudes which will be at sub-solar conditions at this time area near 110 West and 70 East longitude. These include in the West regions of the Rocky Mountains and western North America and in the east Afghanistan and Central Asia. These areas may see enhanced seismicity due to tidal effects over the next week. Seismicity may shift to times closer to local solar noon and midnight during this period, and a moderately large earthquake is possible at this time due to tidal triggering." (January 24-25, 2021)

 

Forecast 130642 had expected today's activity was likely around January 27.

 

O: 24JAN2021 11:54:13  36.5N   71.4E mb=4.3  EMSC   HINDU KUSH REGION, AFGHANISTAN

P: 27JAN2021 130642    36.0N   70.0E 3.8-5.2 BAAAA  Hindu Kush/Pakistan        

 

O: 24JAN2021 19:01:21  37.1N   71.7E mb=5.2  EMSC   TAJIKISTAN                   

P: 20JAN2021 130336    37.0N   71.0E 3.8-5.3 BAAAA  Hindu Kush/Pakistan        

P: 27JAN2021 130642    36.0N   70.0E 3.8-5.2 BBAAA  Hindu Kush/Pakistan        

 

The strongest earthquake in the U.S. or Canada today was an M 5.4 in the Alaska Peninsula aftershock zone of the October 19, 2020 mainshock. NEIC reported this earthquake of M 5.4 in  the Alaska Peninsula was felt with intensity IV in the area(s) of  the Alaska Peninsula at King Cover and Sand Point. This epicenter was probably enhanced by energy from the M 7.1 in the South Shetland Islands of January 23, 2021 as it lies at 143 degrees from that event, a distance at which energy is concentrated by reflection and refraction off core boundary and redirected to this distance on the surface after large earthquakes. A similar M 5.2 in Taiwan today occurred at 143 degrees from the South Shetland Islands. At M 5.1-5.4, this is the strongest earthquake within about 150 km of this epicenter since an M 5.5 on August 8, 2020, following the major earthquake of M 7.8 in the Alaska Peninsula July 2, 2020. Forecast 130746 had expected today's activity was likely around January 24.

 

O: 24JAN2021 21:16:21  54.5N  162.2W mb=5.4  EMSC   ALASKA PENINSULA             

O: 24JAN2021 21:16:22  54.4N  162.1W mb=5.1  ANSS   ALASKA PENINSULA             

P: 24JAN2021 130746    54.3N  161.4W 3.5-5.1 AAAAA  Unimak Islands, Aleutians  

 

An M 5.4-5.5 aftershock also occurred in the South Shetland Islands today and was accompanied by a series moderate shocks. This follows the M 7.1 in the region of January 23. Several of today's events occurred near local solar noon and were probably promoted by high tidal stresses which maximize at this hour. An earthquake near 103 degrees from this occurred in the San Fernando Valley of Southern California with M 2.2. This is an area which, in the past, has been activated by strong earthquakes in the South Shetland Islands. Forecast 130813 had expected this activity in the South Shetland Islands  was likely around January 23.

 

O: 24JAN2021 12:14:45  61.7S   55.2W Mw=5.5  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 09:29:05  61.8S   55.2W mb=4.7  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 13:40:49  61.8S   55.4W mb=4.9  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 20:34:13  61.8S   55.3W mb=4.8  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 18:11:01  61.6S   55.1W mb=4.9  EMSC   SOUTH SHETLAND ISLANDS       

P: 23JAN2021 130813    61.0S   58.0W 4.0-5.5 AABAA  Southern  Ocean            

 

Two moderate earthquakes in the south Atlantic also occurred today with an M 5.1 southwest of Africa and an M 4.8 east of South Sandwich Islands. These had not been anticipated in this summary. They were unusual and were probably  triggered by energy from the South Shetland Islands. The last event within about 300 km of the M 4.8 East of the South Sandwich Islands  with similar or larger magnitude was an M 5.0 west of this on September 10, 2019 and prior to that an M 5.3 on November 15, 2017.

 

O: 24JAN2021 10:26:06  58.4S   14.6W mb=4.8  EMSC   EAST OF SOUTH SANDWICH ISLANDS

 

The M 5.1 in the area southwest of Africa is at the antipode of the western Andreanof Islands in Alaska. A moderate event in that area may follow within days. The last earthquake of M>=5.1 within about 200 km of this epicenter was an M 5.9 on August 9, 2020 and prior to that an M 5.3 and 5.1 in December, 2019 and January 2020.

 

 

O: 24JAN2021 15:11:13  52.9S   10.1E mb=5.1  EMSC   SOUTHWEST OF AFRICA          

 

UNPRECEDENTED MAJOR EARTHQUAKE IN SOUTH SHETLAND ISLANDS, ANTARCTICA

 

EARTHQUAKE SUMMARY FOR JANUARY 23, 2021

 

The strongest earthquake in the world today was an M 6.9-7.1 in the South Shetland Islands south of Chile. NEIC reported it was felt with light intensity as far as Punta Arenas, Magellanes, Chile. GUC reported this earthquake of  7.1 was felt with intensity  III in  Magallanes and Antartida, Chilena at Antartida.

In addition to being the largest earthquake in the world since an M 7.6 in the

Alaska Peninsula October 19, 2020, this M 7.1 is the first in the South Shetland Islands within about 400 km of this epicenter of M>=7.0 since an M 7.0 on July 11, 1983 and a similar M 7.0 on November 18, 1941 and the strongest recorded in this area, tied with an M 7.0-7.1 on February 8, 1971. This began the same time as solar flare 5990 - a B1.3 event - and may have been promoted by SFE. This epicenter is near 103 degrees from the M 5.8 in New Guinea which occurred yesterday and at the third node (120 degrees) from both the M 7.0 in the Dodecanese Islands of October 20, 2020 and the M 7.0 in the Philippines of

January 21 - the last two major earthquakes in the world - and may have been promoted by energy from these sources as well.

 

The South Shetland Islands most recently became active in late August 2020 and as seen an M 5.8 on October 2, 2020 and an M 6.0 on November 6, 2020. The last earthquakes of M>6 in this area occurred on January 15, 2012 with M 6.6 and on June 17, 1992 with M 6.2. The event in 2012 was followed by an M 4.89 a month later in southern California and an M 4.5 in Los Angeles on August 8, 2012 while the event in June, 1992 was followed 11 days later by the M 7.3 Lander earthquake east of Los Angeles, California on June 28, 1992. Events in the South Shetland Islands of M 7.0 in November, 1941 were accompanied by an M 5.5 in the Los Angeles area and an M 6.0 Coalinga quake in July 1983. The reason this may be important is that southern California is at 103-105 degrees from the South Shetland Islands, a distance at which strong energy concentration occurs following major earthquakes due to reflection and  refraction off core-mantle boundaries of seismic energy. It is of particular note that the largest earthquake in the South Shetland Islands prior to today's occurred on February 8, 1971 (M 7.0-7.1) because less than a day later, an M 6.7 did much damage in the Los Angeles, California area (the San Fernando quake).

 

With this in mind this summary is placing southern California and especially areas of Los Angeles and south of that under a seismic watch through early February 2021. A seismic watch means that historical conditions exist such that a significant or enhanced earthquake could  hit the area in this period or thereafter in the short-term. In addition, because of the unusual nature of this event, much stress may have been propagated to far-field locations and global seismicity is expected experience a marked increase in the next several days.

 

Forecast 130813 had expected today's event within about 100 km was likely around January 23, 2021. This epicenter is located at 143 degrees from the Alaska Peninsula event of M 7.6 on October 19, 2020 and near the third node from the Dodecanese Islands an the Philippine and may have been promoted by energy from those source.

 

O: 23JAN2021 23:48:38  61.7S   55.2W mb=5.4  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 00:05:51  61.7S   55.5W mb=4.9  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 00:51:35  61.7S   55.4W mb=5.0  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 05:29:31  61.7S   55.1W mb=5.0  EMSC   SOUTH SHETLAND ISLANDS

O: 24JAN2021 00:03:16  61.9S   55.4W mb=5.0  EMSC   SOUTH SHETLAND ISLANDS

O: 23JAN2021 23:36:52  61.7S   55.2W Mw=7.1  EMSC   SOUTH SHETLAND ISLANDS       

O: 23JAN2021 23:36     61.7S   55.0W mb=7.1  GUC    Magallanes and Antartida, Chil

P: 23JAN2021 130813    61.0S   58.0W 4.0-5.5 AABAA  Southern  Ocean            

  

An earthquake of M 5.8 was also felt widely in the Santiago area of Central Chile today. NEIC reported maximum intensity V in Graneros, O'Higgins with IV ikn the Santiago, Chile area at Puente Alto, Lampa, Paine, Penaflor, Talagante and III in San Bernardo, Buin and San Felipe, Valparaiso. A foreshock to the east in Mendoza, Argentina of M 4.2 was felt with intensity III in Mendoza and Corrientes, Argentina. Large earthquakes in this area of Chile occur almost exclusively to the west of this epicenter by about 150+ km. The last earthquake within about 150 km of this epicenter with M>=5.8 as an M 6.4 on June 16, 2000. Forecast 130794 had expected today's event within about 100 km was likely around January 27. This epicenter is located at 145 degrees from the Philippines quake of M 7.0 on January 21, 2021 and may have been promoted by energy from that source.

 

O: 24JAN2021 00:07:44  33.4S   70.2W Mw=5.8  EMSC   REGION METROPOLITANA, CHILE  

P: 27JAN2021 130794    33.0S   71.0W 4.0-5.7 BAAAA  Central Chile              

 

An unusual earthquake of M 5.8 also occurred today in the Auckland Islands, New Zealand. It was not reported felt in this remote epicentral area. This is the strongest earthquake in the Auckland Islands since an M 6.1 on September 20, 2017. Forecast 130807 had expected regional seismic enhancement was likely around January 28.  This epicenter is located at 146 degrees from the Dodecanese  quake of M 7.0 on October 30, 2020 and may have been promoted by energy from that source.

 

O: 24JAN2021 05:47:53  51.2S  162.1E Mw=5.8  EMSC   AUCKLAND ISLANDS, N.Z. REGION

P: 28JAN2021 130807    47.0S  165.0E 3.0-5.1 BCBAA  Southern S. Isl. N.Z.      

 

 

MODERATE QUAKE SHAKES PAPUA NEW GUINEA

 

EARTHQUAKE SUMMARY FOR JANUARY 22, 2021

 

The strongest earthquake in the world today was an M 5.7 in eastern Papua New Guinea. NEIC reported it was felt with intensity II-III in Papua New Guinea at Lae Morbe and Bulojo. The last earthquake within about 200 km of this epicenter in New Guinea with M>=5.7 was an M 6.3 on October 8, 2020. The last such event within about 100 km of this epicenter was an M 6.0 on December 1, 2017. Forecast 130249 had expected this area of New Guinea would see enhanced seismicity within about 100 km of this epicenter in mid-January. This epicenter is at the third node (120 degrees) from the M 7.0 in the Dodecanese Islands of October 30, 2020 and also at 120 degrees from the M 6.7 in Los Lagos, Chile of December 27, 2020 and may have been promoted by energy from those source.

 

O: 23JAN2021 03:19:50   6.3S  147.6E Mw=5.7  EMSC   EASTERN NEW GUINEA REG., P.N.G

P: 16JAN2021 130249     6.0S  147.0E 4.0-5.4 CAAAA  New Ireland                

 

A moderate earthquake of M 5.4-5.6 also shook the Kermadec Islands in northern New Zealand today. It was not reported felt in this remote area. Most of the larger events in this region in the past several months have occurred west of this epicenter on the other side of the IDL. The last earthquakes of M>=5.4 in this region of the Kermadec Islands within about 150 km of today's epicenter occurred as an M 5.9 on December 10, 2020 and an M 7.3 and immediate aftershocks on June 17, 2020. This may be an aftershock of the June, 2020 event. Forecast 130802 had expected today's event within about 100 km was likely around January 25.

 

O: 22JAN2021 16:23:36  33.4S  178.8W Mw=5.4  EMSC   SOUTH OF KERMADEC ISLANDS    

O: 22JAN2021 16:23:42  33.2S  179.4W Mw=5.6  ANSS   SOUTH OF KERMADEC ISLANDS    

P: 25JAN2021 130802    34.0S  180.0W 4.0-5.4 BAAAA  So. Kermadec Islands       

 

The largest earthquake in the U.S. or Canada today was an M 3.4 in Baja California near the border with California. The M 3.4 today is the largest in the area since an M 3.4 on January 6 and an M 3.6 on December 28, 2020. Forecasts 130359 and 130666 had expected today's activity in mid-January  within about 50 km of today's epicenter.

 

NEIC reported this earthquake of M 2.9-3.4 in Southern California was felt with intensity II-III in the area(s) of Southern California at Thermal and Palm Springs.

 

O: 22JAN2021 07:20:46  32.0N  115.3W ML=3.4  EMSC   BAJA CALIFORNIA, MEXICO

O: 22JAN2021 13:43:43  32.3N  115.4W Ml=2.0  EMSC   BAJA CALIFORNIA, MEXICO

O: 22JAN2021 14:26:51  32.3N  115.4W Ml=2.0  EMSC   BAJA CALIFORNIA, MEXICO      

P: 17JAN2021 130359    33.0N  115.9W 2.5-4.6 BAAAA  So. California             

P: 25JAN2021 130666    32.6N  116.1W 2.5-4.6 BAAAA  So. California             

 

EARTHQUAKES SHAKE CENTRAL PERU, SEA OF OKHOTSK, RUSSIA

STRONG QUAKE SHAKES SOUTHERN MINDANAO, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR JANUARY 21, 2021

 

 

The strongest earthquake in the world today was an M 7.0-7.1 south of Mindanao, Philippines. NEIC reported it was felt in the Southern Mindanao area with maximum intensity VI in Buayan and Katangawan; V in Mayo, Klinan, Padada, Baganga, Polomolok and Satorga and III in Pundaguitan. PHIVOLCS reported this earthquake at M 7.1 was felt with intensity V in Jose Abad Santos, Davao Occidental; Governor Generoso, Davao Oriental; Kiamba, Glan, Maitum and Malungon, Sarangani; Mailta, Davao Occidental; General Santos City; Rosario and Talacogon, Agusan Del Sur; Carmen and Lingig, Surigao Del Sur; Babini, Pantukan, Davao de Oro; IV in Mati City, Davao City; Cotabato City, Digos City; Sta Cruz, Davao del Sur, Alabel, Maasim and Malapatan, Sarangani; Tagum City, Davao Del Norte, Koronadal City, Tupi, Lake Sebu, Banga, and Polomolok, South Cotabato, Sta Maria, Davao Occidental, Bagumbayan, SultanKudarat; Maco, Maragusan, New Bataan, Compostels and Mawab, Davao de Oro; III ikn San Francisoc, Southern Leyte, Datu Blah T. Sainsuat, Maguindanao; Zamboanga City, Cagayan, De Oro City, Tandag City, and Cantilan, Surigao Del Sur, Sto Nino, South Cotabato, Bansalan, Davao Del Sur, Lambayong, Sultan Kudarat; Arakan, Cotabato and I-II as far as Surigao City, Philippines. This is the strongest earthquake in the world in nearly three months - after a similar M 7.0 in the Dodecanese Islands, Greece on October 30, 2020. This may have been promoted by strong tidal stresses associated with the last new moon as previously noted in this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 12-18, 2021)

 

Today's event is the strongest within about 200 km of this epicenter since an

M 7.0 on December 29, 2018. The last of larger magnitude was an M 7.2 about 200 km southwest of this on February 11, 2009.  Forecast 130233 had expected today's event about 200 km to the southwest was likely around January 19 in the Mindanao area. The coast of California is near 103 degrees from the epicenter of this earthquake in the Philippines and may see enhanced seismicity related to incoming energy from this source in the near future.

 

O: 21JAN2021 14:40:30   5.0N  127.3E mb=4.5  EMSC   PHILIPPINE ISLANDS REGION

O: 21JAN2021 16:37:31   5.0N  127.4E mb=4.6  EMSC   KEPULAUAN TALAUD, INDONESIA

O: 21JAN2021 12:23:04   5.0N  127.5E Mw=7.0  EMSC   PHILIPPINE ISLANDS REGION    

P: 19JAN2021 130233     4.0N  126.0E 4.0-5.6 AABAA  Mindanao, Philippines      

 

An M 3.0 in the northern San Francisco area of California today was felt with intensity II-III at Concord, Pleasant Hill, Walnut Creek, Lafayette and Martinez, California according to NEIC. Forecast 130634 had expected this event within about 15 km was likely around January 24. This earthquake is at 103 degrees from the M 7.1 in Mindanao, Philippines, a distance where energy is concentrated on the surface after large earthquake. Subsequent seismicity is often enhanced at 103 degrees from large earthquakes. Watch for further enhancement in the area of Central and Northern California in the next week.

 

O: 22JAN2021 00:48:10  38.0N  121.9W ML=2.7  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 22JAN2021 00:48:10  38.0N  121.9W ML=3.0  ANSS   SAN FRANCISCO BAY AREA, CALIF.

P: 24JAN2021 130634    37.9N  122.0W 2.5-4.5 AAAAA  Central California         

 

A strong swarm of minor earthquakes was felt in the Dominican Republic today. This contained at least a dozen event of M>=3. It may be related to the landfall of Tropical Storm 14S at the antipode in western Australia today as noted in this and previous summaries:

 

"Tropical cyclone 14S formed north of western Australia today with winds up to 50 kts. It is expected to make landfall today south of Broome, Australia. Some seismicity at the antipode near the Virgin Islands, Puerto Rico and the Dominican Republic, Caribbean may be triggered by antipodal energy concentration from this storm." (January 21, 2021)

 

Forecast 130298 had expected today's activity in the Dominican Republic was likely around January 19. This activity is also at 146 degrees from the M 7.0 in the Philippines and may have enhanced by energy from that source.

 

O: 21JAN2021 13:30:16  20.3N   70.8W ML=3.0  EMSC   DOMINICAN REPUBLIC REGION

O: 21JAN2021 07:10:33  20.5N   71.0W ML=3.1  EMSC   DOMINICAN REPUBLIC REGION

O: 21JAN2021 07:49:57  20.5N   71.2W ML=3.1  EMSC   DOMINICAN REPUBLIC REGION

O: 21JAN2021 12:50:44  19.2N   70.1W ML=3.3  EMSC   DOMINICAN REPUBLIC

O: 21JAN2021 11:21:10  19.2N   70.1W ML=3.6  EMSC   DOMINICAN REPUBLIC           

O: 20JAN2021 21:18:31  20.2N   71.0W ML=3.1  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 15:07:43  20.3N   70.9W ML=3.6  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 18:15:25  20.3N   70.9W ML=4.0  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 20:12:14  20.3N   70.8W ML=3.6  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 21:13:02  20.3N   71.0W ML=3.1  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 21:59:48  20.3N   70.8W ML=3.5  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 22:30:13  20.3N   70.8W ML=3.4  EMSC   DOMINICAN REPUBLIC REGION

O: 21JAN2021 00:30:08  20.3N   70.9W ML=3.5  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 20:41:32  20.5N   70.9W ML=3.3  EMSC   DOMINICAN REPUBLIC REGION

O: 21JAN2021 03:55:17  20.5N   70.9W ML=3.2  EMSC   DOMINICAN REPUBLIC REGION

O: 20JAN2021 19:26:05  19.5N   70.2W ML=3.2  EMSC   DOMINICAN REPUBLIC           

P: 19JAN2021 130298    20.0N   71.0W 3.0-4.7 AAAAA  Bahamas/No. Caribbean      

 

A pair of light but unusual earthquakes in Western Australia also accompanied landfall of TC 14S. These occurred as this storm passed over the epicenters and were probably triggered by stresses related to TC 14S. The last earthquake within about 200 km of today's M 3.4 with equal or greater magnitude was an M 4.4 on June 15, 2019 and prior to that an M 4.5 on June 19, 2017 and July 14, 2011. Forecast 130791 had expected regional enhancement in seismicity in later January.

 

 

O: 21JAN2021 17:52:44  18.2S  120.3E ML=3.1  EMSC   WESTERN AUSTRALIA            

O: 22JAN2021 05:23:48  22.6S  120.1E ML=3.4  EMSC   WESTERN AUSTRALIA            

P: 26JAN2021 130791    30.0S  117.0E 2.0-3.9 BCBAA  Central Australia          

 

 

EARTHQUAKE SUMMARY FOR JANUARY 20, 2021

 

The strongest earthquake in the world today was an M 5.5 in Central Peru. NEIC reported it was felt with maximum intensity VI in Ica Peru at Marcona and Palpa; V in Nazca, Santiago, Vista Alegre, and Pisco and IV in Los Aquijes, Acari, San Juan Bautista and San Clemente. Moderate foreshocks of M 4.8, 5.3 and M 5.1 shook Nazca with intensity III-IV. NEIC reported aftershocks of M 4.8 and M 5.3 in Central Peru were felt with intensity II-III in the area(s) of Central Peru at Vista Alegre, Ica. This activity was likely promoted by strong tidal stresses associated with the new moon of January 13 as it occurred at the longitude where such stresses were maximized at the time as noted in previous issues of this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 12-18, 2021)

 

Forecasts 130475 and 130762 had expected today's activity between January 17 and 23 to the east of today's epicenter in Central Peru. An M 7.1 hit the region about 100 km southeast of today's epicenter on January 14, 2018 but the last event of M>=5.5 within about 200 km of today's epicenter occurred as an M 5.7 on December 27, 2020 and an M 5.6 on October 28, 2020. This activity is located at 144 degrees from the M 6.7 quake in Mongolia of January 11, 2021, the largest earthquake of the current year. Seismic energy is concentrated at this distance from major surface disturbances after reflection and refraction off core boundaries and can help promote further seismicity at this distance.

 

O: 20JAN2021 22:59:12  15.0S   75.6W Mw=5.5  EMSC   NEAR COAST OF CENTRAL PERU

O: 20JAN2021 23:09:16  15.0S   75.6W Mw=5.3  EMSC   NEAR COAST OF CENTRAL PERU

O: 21JAN2021 00:27:45  15.0S   75.6W mb=4.8  EMSC   NEAR COAST OF CENTRAL PERU

O: 20JAN2021 22:27:42  15.1S   75.7W Mw=5.1  EMSC   NEAR COAST OF CENTRAL PERU

O: 20JAN2021 22:49:26  15.0S   75.6W mb=4.8  EMSC   NEAR COAST OF CENTRAL PERU   

P: 17JAN2021 130475    15.0S   73.0W 4.0-5.8 BABAA  Central Peru               

P: 23JAN2021 130762    15.0S   73.0W 4.0-5.8 BABAA  Central Peru               

 

An M 5.5 in the Sea of Okhotsk, Russia also occurred today. NEIC reported it was felt with intensity V in Toyohara, Sakhalin, Russia. This deep focus earthquake (575 km depth) is the strongest in the Sea of Okhotsk within about 300 km of this epicenter since an M 6.0 on November 2, 2018; an M 5.7 on July 23, 2016 and an M 5.5 on November 23, 2005. The largest, and only event in the region with M>6 in the past 30 years was an M 7.3 on November 17, 2002. Forecast 130446 had expected today's event within about 35 km of this epicenter was likely around January 20.

 

O: 20JAN2021 16:00:40  49.7N  147.8E Mw=5.5  EMSC   SEA OF OKHOTSK               

P: 20JAN2021 130446    50.0N  148.0E 4.0-5.6 AAAAA  Sakhalin                   

 

An unusual earthquake of M 4.2 shook central Austria today.

NEIC reported this earthquake of M 4.1-4.2 in Austria was felt with intensity IV in the area(s) of Liezen, Austria and II-III in Austria at Hall Tirol, Micheldorf, Fohnsdorf, Sankt Valentin, Sahladming, Steiermark, Tamsweg, Salzburg, Linz, Linz, Oberosterreich, and in Budweis, Jihocesky, Czech Republic.

The only event of M>=4 in the past year in Austria was an M 4.0 on August 8, 2020. The last earthquake in Austria within about 150 km of today's epicenter with M>=4.3 occurred as an M 4.4 on October 1, 2004. The only event within  this area in the past 8 years within Austria and within about 200 km of today's epicenter was an M 4.3 on December 3, 2012. Forecast 130382 had expected today's event was likely in mid-January in Austria.

 

O: 20JAN2021 07:30:26  47.6N   14.4E ML=4.2  EMSC   AUSTRIA                      

P: 14JAN2021 130382    46.0N   13.0E 3.0-5.2 CBAAA  Austria                    

 

An M 3.3-3.5 in the greater Los Angeles, California area today was reported by NEIC to have been felt with maximum intensity IV in Los Angeles and Compton, California. Moderate earthquakes in this area of Los Angeles have been absent within about 75 km of this epicenter since an M 4.5 on September 19, 2020 and an M 4.2 on July 30, 2020. Forecast 130671 had expected today's event within about 10 km was likely around January 23.

 

O: 20JAN2021 16:31:57  33.9N  118.3W ML=3.3  EMSC   GREATER LOS ANGELES AREA, CALI

O: 20JAN2021 16:31:58  33.9N  118.3W ML=3.5  ANSS   GREATER LOS ANGELES AREA, CALI

P: 23JAN2021 130671    33.9N  118.3W 2.5-4.6 BAAAA  So. California             

 

 

An unusually large earthquake of M 5.2 occurred in the Gulf of California, Mexico today. It followed an M 4.2 which was probably promoted by strong tidal stresses as it occurred within about 30 minutes of local solar midnight, a time when such stresses maximize. The M 5.2 is the strongest event within about 150 km of its epicenter since an M 5.3 on September 24, 2020 and prior to that an M 6.3 on January 19, 2018.  Forecast 130302 had expected today's activity in this region was possible around January 19. Earthquakes in the Gulf of California can add stress to faults to the north in California promoting further seismicity in that region. The M 3.5 in Los Angeles, California today occurred about 1.5 hours after the M 5.2 in the Gulf of California and may have been enhanced from that event. Both these events in the Gulf of California and the M 3.5 in Los Angeles, California today are at 102-104 degrees from the M 7.0 in the Dodecanese Islands, Greece of October 30 and were probably enhanced by concentrated energy from that source.

 

 

O: 20JAN2021 14:59:48  26.4N  111.0W Mw=5.2  EMSC   GULF OF CALIFORNIA

O: 20JAN2021 07:48:07  26.0N  110.5W ML=4.2  EMSC   GULF OF CALIFORNIA           

P: 19JAN2021 130302    28.0N  112.0W 3.5-4.9 ABBAA  Gulf of California         

 

STRONG GAMMA RAY BURST ASSOCIATED WITH M 6.5 IN ARGENTINA

 

EARTHQUAKE SUMMARY FOR JANUARY 19, 2021

 

Moderate aftershocks continued to be felt in the San Juan, Argentina area today.

The strong, damaging earthquake in San Juan, Argentina early on the morning of January 19, 2021 was probably promoted by effects from a strong GRB, the first since January 12. This GRB was first observed within about 10 minutes of the earthquake in Argentina (02:54 UT vs 02:46 UT) as noted in the EXTERNAL FIELDS section of this report with the following preliminary SWIFT parameters:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on January  19, 2021 at 02:54 UT with BAT Fluence n/a erg/sqcm. (MAGNITUDE: n/a), Associated earthquake: San Juan Argentina 02:46 UT M 6.4)" (January 19, 2021)

 

This summary noted in regard to the Argentina event earlier today:

 

"No major damage was reported. The only similar earthquake in San Juan, Argentina with M>=6.4 in the past 30 years was an M 6.4 on November 20, 2016. That event occurred at an intermediate depth of 116 km but today's event at 5-10 km depth is an unusual shallow focus. The last such event at shallow focus of M>=6 within about 250 km of today's events was an M 6.0 on February 27, 2010, the only such event in the region in the past 30 years. Today's event which occurred near local midnight (at 23:50) was probably promoted by strong tidal stresses associated with the new moon of January 13" (January 18-19, 2021)

 

 

O: 19JAN2021 07:45:50  31.8S   68.8W ML=3.9  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 23:48:29  31.8S   68.8W ML=4.0  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 17:56:17  31.9S   69.0W ML=4.0  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 03:37:48  31.8S   68.7W mb=5.3  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 03:51:53  31.8S   68.9W mb=4.9  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 04:01:42  31.8S   68.8W mb=4.8  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 03:03:43  31.9S   68.8W mb=4.9  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 02:46:21  31.8S   68.8W Mw=6.4  EMSC   SAN JUAN, ARGENTINA          

O: 19JAN2021 02:46     31.8S   69.1W mb=6.5  GUC    Coquimbo at Illapel, Paiguano,

O: 20JAN2021 04:07:48  31.9S   69.0W mb=4.4  EMSC   SAN JUAN, ARGENTINA          

P: 14JAN2021 130507    31.0S   71.0W 4.0-5.9 BABAA  Central Chile              

 

The strongest earthquake in the U.S. or Canada today was an M 3.8 in the Alaska Peninsula aftershock zone. The last earthquake within about 100 km of this epicenter with M >=3.8 was an M 4.7 on December 25, 2020 but more recent events of similar magnitude have occurred on January 4 (M 3.5) and January 14 (M 3.7). Forecast 130430 had expected today's activity was likely around January 17.

 

O: 20JAN2021 02:06:50  54.9N  160.3W ml=3.8  EMSC   ALASKA PENINSULA              

P: 17JAN2021 130430    54.9N  159.7W 3.5-4.9 AAAAA  Alaska Peninsula           

 

An M 3.6 in the Mayotte Region north of Madagascar today renewed seismicity in that region. A similar M 3.6-3.7 quake hit the region on January 13, 2021, the such event in the past two months since an M 3.9 on November 22, an M 4.8 on November 10 and an M 4.5 on September 25, 2020. Throughout the first eight months of 2020 Mayotte was active with a moderate event nearly every week. Today's earthquake occurred as Tropical Storm Eloise made landfall in the area and had been expected in this summary as a possible consequence of that landfall as:

 

"Tropical Cyclone Eloise continued today east of Madagascar with winds up to 65 kts. It is expected to track to the east over the next several days possibly enhancing seismicity in the Mayotte area." (January 18-19, 2021)

 

Forecast 130478 had expected today's event in the Mayotte or Madagascar area in mid-January. This epicenter is at 104 degrees from the Los Lagos, Chile M 6.7 of December 27, 2020 and may have been promoted by energy from that source. Earthquakes in Vancouver, Canada were at a similar distance from Los Lagos.

 

O: 20JAN2021 04:07:12  12.8S   45.5E ML=3.6  EMSC   MAYOTTE REGION               

P: 14JAN2021 130478    13.0S   44.0E 3.0-4.4 CABAA  Madagascar area            

 

 

 

 

 

STRONG QUAKE SHAKES CHILE AND ARGENTINA

 

EARTHQUAKE SUMMARY FOR JANUARY 18, 2021

 

A strong M 6.4-6.8 earthquake was widely felt in Chile and Argentina today. It was reported by NEIC to have been felt with maximum intensity VI in Argentina at San Juan; V in San Martin, Mendoza and IV in Mendoza. In Chile it was reported with V in Llaillay, Valparaiso; IV in Valparaiso at San Felipe, La Ligua, Calera and in Santiago with lesser shaking of III in Los Andes, Cabildo, Valparaiso. GUC reported it at M 6.5 and that it was felt with intensity  V in  Coquimbo at Illapel, Paiguano, Vicuna; IV in Salamanca, Monte Patria, La Serena, Combarbala, III in Andocollo, Coquimbo, La Higuera, Ovalle, Rio Hurtado and II in Canela, Los Vilos, in Atacama with IV in Alto del Carmen; III in Copiaopo, Freirina, Tierra Amarilla, Vallenar and II in Huasco; in Valparaiso with V in La Lgua, Quilpue, Valparaiso, Zapallar; IV in Catemu, El Tabo, San Antonio, San Felipe, Santa Maria, Villa Alemana and III in Casablanca; in Santiago with V in Macul, Melipilla, and San Jose de Maipo; IV in El Bosque, Las Condes, Pedro Aguirre Cerda, Penalolen, Providencia, Pudahuel, Quinto Normal and III in La Florida, Maipu, Santiago and II in Puente Alto and Recoleta; in O'Higgins with IV in Mostazal, Rancagua and III in Chepica, Lolol, Peumo, Santa Cruz and in Maule with III in Curico, Rauco and II in Pencahue and Sagrada Familia, Chile. No major damage to people or services was reported by GUC. No tsunami was reported. Aftershocks of M 5.3, 4.8 and 4.9 were also felt in the area. Authorities in the area reported no injuries but damage impacted streets and highways in San Juan.

Some locations saw power cuts and damage occurred to homes in the town of Caucete with others evacuated in Zonda, San Juan. No major damage was reported. The only similar earthquake in San Juan, Argentina with M>=6.4 in the past 30 years was an M 6.4 on November 20, 2016. That event occurred at an intermediate depth of 116 km but today's event at 5-10 km depth is an unusual shallow focus. The last such event at shallow focus of M>=6 within about 250 km of today's events was an M 6.0 on February 27, 2010, the only such event in the region in the past 30 years. Today's event which occurred near local midnight (at 23:50) was probably promoted by strong tidal stresses associated with the new moon of January 13 as reported in the forecast for tidal triggering with that alignment in previous issues as:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-12, 2021)

 

An M 4.4 to the west occurred several hours earlier and was reported with maximum intensity IV in Santiago and Coquimbo, Chile and III in San Felipe and Lampa, Chile and III in Mendoza, Argentina. A moderate foreshock hit the same area of Argentina on January 16, 2021. This event of M 4.9 - also near local solar midnight. A larger M 6.1 occurred in Jujuy, Argentina on January 10, 2021 near local solar midnight and was reported here at the time as:

 

"The M 6.1 in northern Argentina was reported by NEIC to have been felt with intensity VI in Salta, Argentina; IV in Antofagasta, Chile and II in Iquique, Tarapaca, Chile. It was preceded by an M 4.5 foreshock that was felt with intensity III in Antofagasta. GUC reported this earthquake was felt with intensity  IV in  Antofagasta at Antofagasta, Calams, Mejillones and III in Taltal, Tocopilla; in Tarapaca with III in Iquique and II in El Loa, La Tirana, Pica, Pozo Almonte; and in Atacama with IV in Chararal, Diego de Almagro, El Salvador and III in Copiapo and Tierra Amarillo, Chile. This is the strongest earthquake within about 250 km of this epicenter since an M 6.3 on November 20, 2020 and prior to that an M 6.3 on April 15, 2017. ... The quake occurred within about 30 minutes of local solar midnight and may have been enhanced by strong tidal stresses which are maximized at this hour. Maximum stress with the next full moon on January 13 is near this longitude as noted in the tidal forecast" (January 10-11, 2021)

 

Forecast 130507 had expected seismic activation in mid-January about 150 km west of today's epicenter was likely.

 

O: 19JAN2021 03:37:48  31.8S   68.7W mb=5.3  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 03:51:53  31.8S   68.9W mb=4.9  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 04:01:42  31.8S   68.8W mb=4.8  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 03:03:43  31.9S   68.8W mb=4.9  EMSC   SAN JUAN, ARGENTINA

O: 19JAN2021 02:46:21  31.8S   68.8W Mw=6.4  EMSC   SAN JUAN, ARGENTINA          

O: 19JAN2021 02:46     31.8S   69.1W mb=6.5  GUC    Coquimbo at Illapel, Paiguano,

P: 14JAN2021 130507    31.0S   71.0W 4.0-5.9 BABAA  Central Chile              

 

Another M 4.4 occurred earlier in the day in the Yellow Sea of China near South Korea. It was reported felt in South Korea at Taech on Chungchongnam, Mokpo, Cholianam, Haenam, Onyang, Suigen Kyonggi, Seoul, Hwado, Gumi, Changsungoo and Gyeongju with intensity III-IV. This epicenter is in the antipodal area of the later M 6.4 in Argentina. This is the strongest earthquake within about 250 km of this epicenter near South Korea since an M 4.8 near this epicenter on April 20, 2013. Forecast 130400 had expected activation in this area to the northeast around January 20.

 

O: 18JAN2021 18:21:27  35.8N  124.1E mb=4.4  EMSC   YELLOW SEA                    

P: 20JAN2021 130400    41.0N  129.0E 3.5-5.4 ACCAA  NE China                   

 

The strongest activity in the U.S. or Canada today occurred in the region of the Alaska Peninsula with M 4.0 and 3.9. These are not uncommon events in this region of aftershocks of the M 76. of October 19, 2020 and were not reported felt in this area. They had been expected at this time in  forecasts 130430 and 130457.

 

O: 19JAN2021 02:24:15  54.6N  159.6W ml=3.9  EMSC   SOUTH OF ALASKA              

P: 17JAN2021 130430    54.9N  159.7W 3.5-4.9 AAAAA  Alaska Peninsula           

 

O: 18JAN2021 21:43:20  58.3N  156.2W mb=4.0  EMSC   ALASKA PENINSULA             

P: 18JAN2021 130457    60.1N  153.4W 3.2-4.9 ABBAA  Central Alaska             

 

The most widely felt earthquake in the U.S. today was an M 2.7 north of San Francisco. NEIC reported this earthquake of M 2.7 north of San Francisco, California  was felt with intensity II-III in the area(s) north of San Francisco, California in Santa Rosa, Fulton, Windsor, Rohnert Park and Sebastopol. This appears to be part of a regional activation of the past several days which now appears to be diminishing. Forecast 130328 had expected today's event around January 19.

 

O: 19JAN2021 04:22:20  38.5N  122.7W Md=2.7  EMSC   NORTHERN CALIFORNIA          

P: 19JAN2021 130328    38.5N  122.7W 2.5-4.6 AAAAA  Central California         

 

LIGHT SWARM AT MOUNT HOOD, OREGON MAY BE RELATED TO VOLCANIC EPISODE

 

EARTHQUAKE SUMMARY FOR JANUARY 17, 2021

 

A series of light to moderate earthquakes shook the area of Mount Hood, Oregon today. These were reported by NEIC to have been felt with maximum intensity V in Oregon at Hood River and I-III in Government Camp, Mount Hood Parkdale, The Dalles, Gresham, Portland, Oregon. The strongest of today's events in the Mount Hood area was M 2.8. These follow a strong swarm in the Mammoth Lakes area of California several days ago. A strong swarm in Mammoth Lakes in May, 1980 followed the eruption of Mt. St. Helens in Washington about a week later. Some relation between volcanic areas in Washington and Oregon and those in California is possible. The last earthquake of M>=2.8 in the Mount Hood area was an M 2.8 on October 10, 2017. The last of larger magnitude was an M 3.0 on May 14, 2010 and an M 3.3 on July 7, 2003. The strongest earthquake in the area in the past 30 years was an M 4.5 on June 29, 2002.

 

At the time of the June 29, 2002 event this summary noted:

 

"A strong swarm of earthquakes hit the Mt. Hood Oregon area this  morning. This swarm included several Ml>=3 events and a Ml 4.5 earthquake which was the largest earthquake ever recorded in the Mt. Hood region. The previous largest had occurred on Dec. 13, 1974 (Ml 4.1)." (June 30, 2002)

 

"... most significant swarm since 2002 when more than 200 quakes - including a widely felt event of M 4.5 struck the mountain on June 29-30, 2002. Nearly 1400 quakes have hit the mountain in the past 30 years - about half of which have been in these swarms of unknown origin. Of these 180 have been of M>=2.

 

The first swarm in recent years occurred in July, 1980 two months after the eruption of Mt. St. Helens, 100 km away. A connection between the two  swarms was considered at the time but a mechanism could not be determined for such a relation. Quakes increased from 1987 to 1994 and averaged about 15 a year. A second pulse of quakes started in 1998 and ended with the 2002 swarm.

 

The last eruption of Mt. Hood occurred 200 years ago. The 2002 swarm did not appear to have indicated new volcanic unrest." (June 30, 2002)

 

Forecast 130415 had expected today's event was likely at Mount Hood within

about 5 km of these epicenters around January 20. This activity is at the fifth node (72 degrees) from the M 6.7 in Mongolia of January 11, 2021 and may have been promoted by energy from that source.

 

O: 17JAN2021 23:03:54  45.3N  121.7W Ml=2.2  EMSC   MOUNT HOOD AREA, OREGON

O: 17JAN2021 23:24:45  45.3N  121.7W Md=2.2  EMSC   MOUNT HOOD AREA, OREGON

O: 17JAN2021 23:26:21  45.3N  121.7W ML=2.5  EMSC   MOUNT HOOD AREA, OREGON

O: 17JAN2021 23:38:31  45.3N  121.7W ML=2.8  EMSC   MOUNT HOOD AREA, OREGON

O: 18JAN2021 02:15:26  45.3N  121.7W Ml=2.2  EMSC   MOUNT HOOD AREA, OREGON

O: 17JAN2021 23:02:44  45.3N  121.7W Md=2.2  EMSC   MOUNT HOOD AREA, OREGON      

P: 20JAN2021 130415    45.3N  121.7W 2.0-4.4 BAAAA  Oregon state, U.S.         

 

A light earthquake of M 2.8 was felt in southeastern Maine today. NEIC reported it was felt with intensity II-III in Maine at Jonesboro, Columbia Falls, Jonesport, Harrington and Lebanon. This is the strongest earthquake within about 100 km of this epicenter since an M 3.5 on September 25, 2005. More recent quakes of this magnitude or larger slightly outside the 100 km distance as a series (M 2.8-3.2) to the west in late 2006 and an M 3.8 on January 10, 2019. An M 3.0 also occurred northeast of this epicenter on December 9, 2020. At the time this summary noted in this regard:

 

 

"An unusual earthquake of M 3.0 shook regions of south-central Maine today. NEIC reported it was felt with maximum intensity VI in Baileyville and II-III in Robbinston, Calais, Pembroke, Perry, Meddybemps, Baileyville and Whiting and in Saint Andrews, Saint Stephen, New Brunswick, Canada, This event followed a smaller M 2.4-2.7 two hours earlier which was also felt. The M 3.0 is the strongest within about 100 km of this epicenter since an M 3.8 to the east on January 10, 2019 and an M 3.3 on February 9, 2016." (December 10, 2020)

 

Forecast 130065 had expected enhanced seismicity within about 50 km of today's epicenter in mid-January.

 

O: 17JAN2021 18:37:41  44.7N   67.6W ML=2.8  EMSC   MAINE                        

P:  9JAN2021 130065    44.4N   68.2W 2.0-3.8 CAAAA  Maine                      

 

The strongest earthquake in the U.S. or Canada today was an M 3.5 in the Mina, Nevada area. This continues elevated seismicity in the region as discussed in the previous issue of this summary. It was not reported felt. Forecast 130322 had expected this activity around January 18, 2021.

 

O: 17JAN2021 18:12:15  38.2N  118.1W ml=2.0  EMSC   NEVADA

O: 18JAN2021 00:50:38  38.2N  117.7W ml=2.2  EMSC   NEVADA

O: 18JAN2021 05:00:53  38.2N  118.1W ml=3.5  EMSC   NEVADA

O: 17JAN2021 09:20:09  38.2N  118.1W ML=2.3  EMSC   NEVADA                       

P: 18JAN2021 130322    38.0N  118.0W 2.5-4.6 AAAAA  California/Nevada area     

 

The strongest earthquake in the world today was an M 5.4 in the South Sandwich Islands of the South Atlantic. This area has been active in January, 2021 with an M 5.6 on January 4; an M 5.2 on January 8 and an M 5.4 on January 11, 2021.

In the past year most of the strong activity in the South Sandwich Islands has been in the southern section with an M 6.4 in July and an M 6.1 in February, 2020. Earthquakes in this area, like today's are seldom felt. Forecast 130526 had expected today's event was likely within about 100 km in mid-January. This earthquake is located at 104 degrees from the last major earthquake in the world - the M 7.0 in the Dodecanese Islands of October 30,, 2020 and may have been promoted by energy from that source. Other earthquakes at this distance from Greece today occurred in Oaxaca, Mexico, Ecuador, Baja California, Sumbawa, Indonesia and El Salvador.

 

O: 17JAN2021 18:40:43  56.6S   27.3W Mw=5.4  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 14JAN2021 130526    56.0S   28.0W 4.0-5.7 BAAAA  So. Sandwich Islands       

P: 19JAN2021 130526    55.0S   28.0W 4.0-5.8 ABAAA  So. Sandwich Islands       

 

The South Sandwich Islands event was preceded by a near-antipodal M 5.1 in the region of Kamchatka, Russia. This was the only other event of M>=5 in the world today. It was not reported felt in this remote area. Forecast 130437 had expected this event within about 150 km was likely around January 18.

 

O: 17JAN2021 08:31:53  54.0N  161.9E Mw=5.1  EMSC   OFF EAST COAST OF KAMCHATKA  

P: 18JAN2021 130437    53.0N  160.0E 4.0-5.5 AABAA  E. of Kamchatka            

 

CENTRAL AND NORTHERN CALIFORNIA ACTIVE

 

EARTHQUAKE SUMMARY FOR JANUARY 16, 2021

 

The strongest earthquakes in the U.S. or Canada today were an M 4.2-4.4 off the coast of Central California and an M 4.4 off Northern California. These were accompanied by a series inland Central California including an M 4.0.  These follow two events in central California of M>=3.6 in the past two days. These included the M 3.9 in the region of Mammoth Lakes yesterday and an M 3.6 north of  San Francisco the day before. This suggests the area is somewhat unstable at this time, but may also indicate a longer term instability promoted by tidal stresses associated with the new moon of January 13, 2021. Strong to major earthquakes in the region generally occur in association with major solar or geomagnetic events. Earthquakes in this region off Central California have occasionally been followed by stronger earthquakes further to the east in the region of the San Andreas Fault zone. This activity is near 103 degrees from the M 7.0 in the Dodecanese Islands of M 7.0 of October 30, 2020, the last major earthquake in the world and was probably promoted by energy from that source.

 

NEIC reported the earthquake near Monterey Bay, Central California was felt with maximum intensity IV in California at Aromas, San Juan Bautista, Salinas, Watsonville, Castroville, Moss Landing, Gilroy. Aftershocks were also felt in the area. The last earthquakes of M>=4.4 within about 100 km of today's epicenter occurred on October 15, 2019 with M 4.5 north of San Francisco and an M 4.7 fourteen hours later near today's epicenter. The earthquake north of San Francisco this year occurred near the same location as in 2019 on January 14, 2021 at 19:18. Today's earthquake of M 4.4 was expected in this region by forecast 130326 within this area.

 

 

O: 17JAN2021 04:04:36  36.9N  121.6W Md=2.1  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 04:06:03  36.9N  121.6W ML=2.8  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 04:14:10  36.9N  121.6W Md=2.0  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 04:01:26  36.7N  122.0W ML=4.4  EMSC   MONTEREY BAY, CALIFORNIA     

P: 15JAN2021 130326    36.8N  121.3W 2.5-5.0 AAAAA  Central California         

P: 16JAN2021 130326    37.3N  121.6W 2.5-4.9 AAAAA  Central California         

 

An earthquake of M 4.4 also occurred off the coast of northern California today. It was reported by NEIC to have been felt lightly in Ferndale, McKinleyville, Crescent City and Willits. The last earthquake of M>=4.4 within about 75 km of this epicenter off northern California occurred on March 9, 2020 with M 5.8 and an aftershock of M 4.9 3.5 hours later. An M 4.4 also hit the region on March 24, 2019. Forecast 130409 had expected today's event was likely within about 30 km of this epicenter around January 16. This event occurred near local solar midnight and may have been promoted by tidal stresses.

 

O: 17JAN2021 06:25:11  40.3N  125.6W Mw=4.4  EMSC   OFFSHORE NORTHERN CALIFORNIA 

P: 16JAN2021 130409    40.5N  125.8W 2.5-4.8 AAAAA  Off Coast of No. Calif     

 

A series of light earthquakes in the East Tulare County area of Central California also occurred earlier in the day. This event is to the east near the Nevada border. NEIC reported it was felt with intensity II-III in East Tulare County, Lone Pine, Springville, Inyokern, Kernville, Onyx, Three Rivers, Lake Isabella, Porterville, and Wofford Heights. Associated shocks of M 3.2 and 3.8 followed and were lightly felt in the area. An M 5.5 hit east of this on June 4, 2020 and was followed by an M 4.2 about an hour later within about 25 km of today's epicenter. A second M 4.2 hit this area to the north by about 30 km on September 11, 2020, the last such event in this region. Forecast 130319 had expected today's event within about 30 km was likely around January 14.

 

 

O: 17JAN2021 02:53:12  36.2N  118.1W ML=2.5  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 02:57:51  36.2N  118.1W ML=2.5  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 03:14:49  36.2N  118.1W Mw=3.8  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 03:30:32  36.2N  118.1W ML=3.0  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 03:31:46  36.2N  118.1W ML=2.5  EMSC   CENTRAL CALIFORNIA

O: 17JAN2021 02:49:08  36.2N  118.1W Mw=4.0  EMSC   CENTRAL CALIFORNIA           

P: 14JAN2021 130319    36.3N  117.8W 2.5-4.7 BAAAA  California/Nevada area     

 

The strongest earthquake in the world today occurred in Hindu Kush, Afghanistan with M 5.5. NEIC reported it was felt with intensity V in Afghanistan at Faizabad and IV in Handud, Kabul, Mardan, Pakistan, Dushanbe and Navabadski,  Tajikistan,  and with lesser intenstiy in Peshawar and Mingaora, Pakistan, Nurak, Tajikistan and Mahmoud Raqui, Afghanistan. This is the strongest earthquake in Afghanistan since an M 5.6 on June 16, 2020 and prior to that

an M 6.1 on December 20, 2019. Forecast 130336 had expected today's earthquake within about 50 km was likely around January 20, 2021.

 

O: 16JAN2021 20:02:44  36.5N   70.8E mb=5.5  EMSC   HINDU KUSH REGION, AFGHANISTAN

P: 20JAN2021 130336    37.0N   71.0E 3.8-5.3 BAAAA  Hindu Kush/Pakistan        

 

STRONG EARTHQUAKE OFF SOUTHERN GUATEMALA

 

EARTHQUAKE SUMMARY FOR JANUARY 15, 2021

 

The strongest earthquake in the world today was an M 5.9 off the coast of Guatemala. NEIC reported it was felt with maximum intensity VII in Champerico, Retalhuleu, Guatemala d IV in Quetzaltenango with lesser shaking in Chimaltenango, Sacatepequez, Itzapa, and Escuintla. The mainshock was followed by several aftershocks including an M 4.9 felt with intensity III in Santa Catarina Pinula, Guatemala. This may have been promoted by high tidal stresses associated with the new moon as noted in previous issues of this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-12, 2021)

 

This is the largest earthquake in the region of Guatemala in the past year - an

M 5.8 occurred near this epicenter on August 4, 2020. The last earthquake in the area of M>5.9 was an M 6.6 on February 1, 2019 and prior to that an M 6.1 on October 28, 2018. Forecast 130274 had expected today's activity in Guatemala was likely around January 17. This earthquake activity is located at 103 degrees from the M 7.0 in the Dodecanese Islands, Greece of October 30, 2020 - the last major earthquake in the world. It was likely promoted by concentrated energy from that source. A series of moderate earthquakes at this distance from Greece also occurred today in Ecuador today, and were probably also promoted by tidal stresses and by energy from the Dodecanese Islands.

 

O: 15JAN2021 23:41:07  13.3N   91.8W mb=4.1  EMSC   OFFSHORE GUATEMALA

O: 16JAN2021 04:27:06  13.7N   92.4W ML=4.1  EMSC   OFFSHORE GUATEMALA

O: 15JAN2021 18:47:05  13.8N   92.1W ML=4.0  EMSC   OFFSHORE GUATEMALA

O: 15JAN2021 16:10:50  14.0N   92.1W Mw=5.9  EMSC   OFFSHORE GUATEMALA

O: 15JAN2021 18:00:02  14.1N   92.8W ML=4.0  EMSC   OFFSHORE CHIAPAS, MEXICO

O: 15JAN2021 21:32:59  14.1N   91.9W mb=4.9  EMSC   OFFSHORE GUATEMALA           

P: 17JAN2021 130274    13.0N   91.0W 3.5-5.3 AAAAA  Guatemala                  

 

Forecast 130243 had expected this activity in Ecuador was likely around January 15.

 

O: 15JAN2021 10:35:17   1.1N   79.7W mb=4.7  EMSC   NEAR COAST OF ECUADOR

O: 15JAN2021 18:45:49   1.1N   79.7W ML=4.2  EMSC   NEAR COAST OF ECUADOR

O: 15JAN2021 19:37:03   1.1N   79.6W ML=4.3  EMSC   NEAR COAST OF ECUADOR

O: 15JAN2021 23:35:26   1.1N   79.8W ML=4.3  EMSC   NEAR COAST OF ECUADOR

O: 15JAN2021 21:54:46   1.2N   79.7W ML=4.4  EMSC   NEAR COAST OF ECUADOR

O: 15JAN2021 21:56:50   1.2N   79.8W ML=4.0  EMSC   NEAR COAST OF ECUADOR

O: 15JAN2021 19:21:16   1.0N   79.8W mb=4.8  EMSC   NEAR COAST OF ECUADOR        

O: 15JAN2021 23:44:50   2.6S   82.1W ML=4.0  EMSC   OFF COAST OF ECUADOR         

P: 15JAN2021 130243     1.0S   81.0W 4.0-5.7 ABAAA  Ecuador                    

 

A moderate earthquake of M 5.5 was also widely felt in southern Iran today. NEIC reported it was felt with maximum intensity V in Bandar-e Langeh, HJormozgan, Iran and IV and III in the United Arab Emirates and at Dona, Qatar. This is the strongest earthquake in Southern Iran within about 250 km of this epicenter since an M 5.8 and 5.5 on June 9, 2020. Forecasts 129973 and 130312 had expected today's event within about 100 km was likely in mid-January.

 

O: 15JAN2021 21:31:05  26.9N   55.3E Mw=5.4  EMSC   SOUTHERN IRAN                

P:  9JAN2021 129973    27.0N   56.0E 3.5-5.1 CAAAA  So. Iran/Persian Gulf      

P: 17JAN2021 130312    28.0N   55.0E 3.5-4.9 ABAAA  So. Iran/Persian Gulf      

 

A series of light earthquakes occurred in the Mammoth Lakes, California area today. The largest of these included an M 3.9 and were felt with intensity II-III in Bishop, June Lake, Benton, California. While a series of events have occurred about 50 km north of today's epicenter in Nevada starting with an M 5.2 on April 11, 2020, this is the strongest event in the Mammoth Lakes area since an M 4.1 on April 5, 2020. Forecast 130320 had expected today's event in this area was likely around January 15. Like activity in Guatemala and Ecuador, this is located near 100 degrees from the Dodecanese Islands and was probably promoted from that source.

 

O: 16JAN2021 00:53:25  37.6N  118.9W Md=2.3  EMSC   LONG VALLEY AREA, CALIFORNIA

O: 16JAN2021 05:08:20  37.6N  118.9W Md=2.0  EMSC   LONG VALLEY AREA, CALIFORNIA

O: 15JAN2021 08:37:26  37.9N  118.6W ml=2.0  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 17:52:08  37.9N  118.6W ml=2.3  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 20:02:03  37.9N  118.6W ml=3.3  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 20:38:11  37.9N  118.6W ML=2.8  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 20:47:01  37.9N  118.6W ML=2.1  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 21:13:21  37.9N  118.6W ml=2.1  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 22:11:07  37.9N  118.5W Mw=3.9  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 22:18:23  37.9N  118.6W ml=2.3  EMSC   CENTRAL CALIFORNIA

O: 15JAN2021 22:50:15  37.9N  118.5W ML=2.8  EMSC   CENTRAL CALIFORNIA

O: 16JAN2021 06:32:14  37.9N  118.6W MD=2.9  EMSC   CENTRAL CALIFORNIA

O: 16JAN2021 06:41:25  37.9N  118.6W Md=2.1  EMSC   CENTRAL CALIFORNIA

O: 16JAN2021 06:52:20  37.9N  118.7W ml=2.9  EMSC   CENTRAL CALIFORNIA

O: 16JAN2021 06:55:27  37.9N  118.5W MD=2.5  EMSC   CENTRAL CALIFORNIA

O: 16JAN2021 06:56:33  37.9N  118.6W ml=3.0  EMSC   CENTRAL CALIFORNIA

O: 16JAN2021 01:03:41  38.0N  118.6W ml=2.0  EMSC   NEVADA

O: 15JAN2021 23:42:42  37.4N  118.6W Md=2.0  EMSC   CENTRAL CALIFORNIA           

P: 15JAN2021 130320    37.4N  118.6W 2.5-4.5 AAAAA  California/Nevada area     

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the eastern Andreanof Islands, Aleutians, Alaska.  This follows an M 4.9 about 100 km northwest of today's event on January 14, 2021. Forecast 130432 had expected today's event in this area was likely around January 17.

 

O: 16JAN2021 03:37:42  52.8N  174.8W mb=4.4  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 17JAN2021 130432    52.2N  173.9W 3.5-5.1 AAAAA  Andreanoff Isls, Aleutians 

 

 

 

 

STRONG EARTHQUAKE IN SULAWESI, INDONESIA

 

EARTHQUAKE SUMMARY FOR JANUARY 14, 2021

 

The strongest earthquake in the world today was an M 6.2 in Sulawesi, Indonesia. NEIC reported it was felt with damage in Sulawesi at Majene and Polewali with lesser shaking at Palu and Dengasar, Bali, Indonesia. BMG reported intensity IV-V in Majene; III in Palu and II in Makasar, Sulawesi, Indonesia. This follows a foreshock of M 5.7 which hit the area yesterday and was noted in this summary in the previous issue as:

 

"The strongest earthquake in the world today was an M 5.7 in Sulawesi, Indonesia. It was not reported felt in this area but was probably felt lightly in the epicentral area. This event occurred within about an hour of local solar noon and was probably enhanced by tidal stresses associated with the new moon as noted in previous issues of this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-12, 2021)

 

It is also located near the geomagnetic equator and may have been promoted by the geomagnetic storm two days ago. Forecast 130260 had expected today's event within about 200 km of this epicenter was likely around January 16. This area often sees a series of moderate to large earthquakes and more such activity may be seen in the next several days. This epicenter is at  the seventh node (51-52 degrees) from the M 6.7 in Mongolia of January 11 and may have been promoted by energy from that source." (January 13-14, 2021)

 

Like the M 5.7 foreshock, the M 6.2 was also probably promoted by high tidal stresses as it occurred near local solar midnight. The last earthquake within about 300 km of today's event of equal or greater magnitude was an M 7.5 on September 28, 2018 about 300 km northeast of today's epicenter. The last within about 250 km was an M 6.3 on August 18, 2012 and prior to that an M 6.3 on January 23, 2005, the largest events in this area in the past 30 years. Forecast 130260 had expected today's event in this area was likely around January 16.

 

O: 14JAN2021 18:41:54   2.9S  118.9E ML=4.0  EMSC   SULAWESI, INDONESIA

O: 14JAN2021 18:28:17   3.0S  118.9E Mw=6.2  EMSC   SULAWESI, INDONESIA

O: 15JAN2021 00:25:27   3.0S  119.0E ML=4.3  EMSC   SULAWESI, INDONESIA

O: 14JAN2021 18:39:55   3.3S  118.7E ML=3.9  EMSC   SULAWESI, INDONESIA          

P: 16JAN2021 130260     1.0S  120.0E 4.0-5.5 ACBAA  Sulawesi area              

 

The most widely felt earthquake in the U.S. today was an M 3.6 in the San Francisco Bay area of California. NEIC reported it was felt with intensity III in Concord, Pleasant Hill, Walnut Creek, Lafayette and Martinez, California among many other communities within about 150 km of the epicenter. This is the strongest earthquake within about 100 km of this epicenter in the San Francisco Bay area since an M 4.3 on July 16, 2019. Forecast 130327 had expected this earthquake was likely around January 12 within about 10 km of the epicenter. The M 3.6 occurred within about 45 minutes of local solar noon, a time when tidal stresses are maximized and may have been promoted by those stresses which are high with the new moon.

 

O: 14JAN2021 19:26:24  38.0N  122.0W Md=2.2  EMSC   SAN FRANCISCO BAY AREA, CALIF.

O: 14JAN2021 19:18:10  38.0N  122.0W Mw=3.6  EMSC   SAN FRANCISCO BAY AREA, CALIF.

P: 12JAN2021 130327    37.9N  122.0W 2.5-4.9 AAAAA  Central California         

 

The strongest earthquake in the U.S. or Canada today was an M 4.0-4.7 in Hawaii. NEIC reported it was felt with intensity V in Pahala and IV in Captain Cook and II-III in Hawaii National Park, Naalehu, Volcano, Pahoa, Mountain View, Hilo and Holualoa and Kurtistown. This is part of the continuing eruption of Kilauea Volcano on Hawaii but is the strongest event in the region since the current eruption began. An M 4.7 hit north of this on July 27, 2020 but the last in the area of Kilauea was an M 5.3 on March 13, 2019 and at the end of the previous eruption on August 2, 2018. Forecast 130276 had expected a moderate quake in Hawaii was likely in mid-January.

 

O: 15JAN2021 04:15:09  19.2N  155.4W mb=4.7  EMSC   ISLAND OF HAWAII, HAWAII     

P: 12JAN2021 130276    19.2N  155.1W 3.0-4.5 BAAAA  Hawaii                     

 

An unusual earthquake of M 2.9 was felt in the Panhandle of Texas today with intensity IV in Amarillo and Panhandle, Texas. The last earthquake with M>=2.9 within about 100 km of today's epicenter was an M 3.7 on October 20, 2018 and prior to that an M 3.1 on February 2, 2015. Forecast 130357 had expected today's event within about 35 km of this epicenter was likely around January 13.

 

O: 14JAN2021 23:30:10  35.2N  101.6W mb=2.9  EMSC   TEXAS PANHANDLE REGION       

P: 13JAN2021 130357    35.4N  101.8W 2.0-4.1 AAAAA  SW U.S.A                   

 

MODERATELY STRONG QUAKE IN SULAWESI, INDONESIA

 

EARTHQUAKE SUMMARY FOR JANUARY 13, 2021

 

The strongest earthquake in the world today was an M 5.7 in Sulawesi, Indonesia.

It was not reported felt in this area but was probably felt lightly in the epicentral area. This event occurred within about an hour of local solar noon and was probably enhanced by tidal stresses associated with the new moon as noted in previous issues of this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-12, 2021)

 

It is also located near the geomagnetic equator and may have been promoted by the geomagnetic storm two days ago. Forecast 130260 had expected today's event within about 200 km of this epicenter was likely around January 16. This area often sees a series of moderate to large earthquakes and more such activity may be seen in the next several days. This epicenter is at  the seventh node (51-52 degrees) from the M 6.7 in Mongolia of January 11 and may have been promoted by energy from that source.

 

O: 14JAN2021 06:35:50   2.9S  118.9E Mw=5.7  EMSC   SULAWESI, INDONESIA          

P: 16JAN2021 130260     1.0S  120.0E 4.0-5.5 ABAAA  Sulawesi area              

 

The strongest earthquake in the U.S. or Canada today was an M 4.9 in the eastern Andreanof Islands, Aleutians, Alaska. It was not reported felt in this remote area. This is the strongest earthquake within about 150 km in the eastern Andreanof Islands since an M 5.3 on October 1, 2020 and prior to that an M 5.0 on February 13, 2020. Forecast 130432 had expected today's activity within about 100 km was likely around January 13.

 

O: 14JAN2021 05:13:52  51.6N  174.0W mb=4.9  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 13JAN2021 130432    51.1N  174.6W 3.5-5.0 AAAAA  Andreanoff Isls, Aleutians 

 

NEW MOON BRINGS ELEVATED SEISMICITY

 

EARTHQUAKE SUMMARY FOR JANUARY 12, 2021

 

The strongest earthquake in the world today was an M 5.9 in New Guinea. NEIC reported it was felt with intensity VIII in Nabire, Papua New Guinea. This is the strongest earthquake within about 200 km of this epicenter since an M 6.1 about 200 km northeast of this and an M 6.3 event five days earlier on June 24 and June 19, 2019. An M 7.0 hit the area on July 27, 2015 and April 6, 2013.

This epicenter is at 103 degrees from southern California and appears to have promoted activity in that area in the past, usually with the strongest triggered events about a month later the the large quake in Papua. Forecast 130263 had expected today's event was likely in mid-January, 2021. This epicenter is near  the sixth node (60 degrees) from the earthquake in Mongolia of January 11, 2020 and may have been promoted by energy from that source.

 

O: 12JAN2021 18:17:33   3.2S  136.9E Mw=5.9  EMSC   PAPUA, INDONESIA             

P: 17JAN2021 130263     3.0S  135.0E 4.0-5.6 BABAA  West Irian, PNG            

 

A series of moderate earthquakes occurred today in southern Greece. NEIC reported these events were felt with intensity V in Rododafni, Ahaia and IV in Lidorikion, Aiyion, Aktaio, Patrai, Demenika,and Agrinon and II-III in Rion, Stirion and Karpenision, Greece. Several aftershocks of M 4.7 were also felt in the area. These events appear to have been promoted by tidal stresses associated with the new moon which arrived within minutes of the M 5.1 in Greece. That event occurred within about 15 minutes of local solar midnight an hour when tidal stresses are maximized. This was noted in this and previous summaries as:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-12, 2021)

 

Local solar midnight occurs at 22:30 UT. The last earthquake within about 150 km of today's epicenter with M>=5.1 occurred as an M 5.3 on February 15, 2016. Forecast 130345 had expected today's activity was likely within about 50 km to occur around January 14, 2021. Today's activity is located near the third node (120 degrees) from the Dodecanese Islands M 7.0 of October 30, 2020 and at the sixth node (60 degrees) from the earthquake in Mongolia of January 11, 2020 and may have have been promoted by energy from those source.

 

O: 12JAN2021 22:29:37  38.4N   22.0E mb=4.6  EMSC   GREECE

O: 12JAN2021 22:32:55  38.4N   22.1E ML=4.1  EMSC   GREECE

O: 12JAN2021 22:56:46  38.4N   22.1E mb=4.5  EMSC   GREECE

O: 12JAN2021 22:09:55  38.4N   22.1E Mw=5.1  EMSC   GREECE                       

P: 14JAN2021 130345    38.0N   22.0E 3.0-4.6 AAAAA  No. Greece                 

 

The strongest earthquake in the U.S. or Canada today was an M 4.3-4.5 off the coast of Northern California. NEIC reported it was felt along the coast with intensity II-III in Northern California at Ferndale, Eureka, Trinidad, Quincy. The last activity within about 100 km of today's event with M>=4.3 was an M 4.8 on March 22, 2020, an aftershock of an M 5.8 on March 9, 2020. Forecast 130409  had expected today's event within about 25 km was likely around January 16, 2021.

 

Exactly 20 years ago an M 5.6 hit this same area off the coast of Northern California. It was widely felt along the coast. For more details see the "HISTORY" section of this summary.

 

O: 13JAN2021 04:12:18  40.4N  124.8W ML=2.7  EMSC   OFFSHORE NORTHERN CALIFORNIA

O: 12JAN2021 18:52:23  40.6N  125.5W ML=3.0  EMSC   OFFSHORE NORTHERN CALIFORNIA

O: 12JAN2021 13:22:02  40.4N  125.5W Mw=4.4  EMSC   OFFSHORE NORTHERN CALIFORNIA 

O: 12JAN2021 13:22:02  40.4N  125.5W Mw=4.3  ANSS   OFFSHORE NORTHERN CALIFORNIA 

P: 16JAN2021 130409    40.5N  125.8W 2.5-4.8 BAAAA  Off Coast of No. Calif     

 

An aftershock of M 4.5 also occurred in zone of the M 7.6 in the Alaska Peninsula today. It was not reported felt in this remote area. This is the largest aftershock in this area since an M 4.7 on December 21, 2020.  Forecast 130430 expected today's event was likely around January 13, 2021.

 

O: 12JAN2021 15:48:34  54.4N  159.7W mb=4.5  EMSC   SOUTH OF ALASKA              

P: 13JAN2021 130430    54.8N  158.7W 3.5-4.9 AAAAA  Alaska Peninsula           

 

The earthquake of M 6.7 in Russia/Mongolia and the M 6.0 in Northern Japan late on January 11 and early on January 12, 2021 were closely associated with a strong GRB which was first recorded early on January 12 about an hour before the quake in Hokkaido, Japan. Effects from this and the associated geomagnetic storm may have helped promote these earthquakes at this time. The specs on the GRB are not yet available but will be published in this report when available. Current data on this GRB is found in the EXTERNAL FIELDS section of this report as:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on January  12, 2021 at 01:37 UT with BAT Fluence n/a erg/sqcm. (MAGNITUDE: n/a), Associated earthquake: Russia/Mongolia M 6.7 1-11 21:32 UT, Northern Japan M 6.0 1-12 02:39 UT)" (January 12-13, 2021)

 

Aftershocks continued today in the Russia-Mongolia area today with the strongest with magnitudes in the mid-fours. Forecast 130447 had expected this activity within about 150 km of this epicenter was likely around January 15.

 

NEIC reported the earthquake of M 4.4 and M 4.7 in Mongolia were felt with intensity II-III in the area(s) of Mongolian in Ulaanbaatr and in  Irkutsk, Russia (IV).

 

O: 12JAN2021 21:55:32  51.3N  100.3E mb=4.4  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 16:31:16  51.4N  100.3E mb=4.5  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 13JAN2021 02:33:26  51.4N  100.3E mb=4.0  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 12:53:13  51.5N  100.5E mb=4.1  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 09:08:45  51.2N  100.4E mb=4.7  EMSC   RUSSIA-MONGOLIA BORDER REGION

P: 15JAN2021 130447    51.0N   98.0E 3.0-4.4 BABAA  So. Siberia                

 

STRONG EARTHQUAKES SHAKE MONGOLIA/SIBERIA AND HOKKAIDO, JAPAN

 

EARTHQUAKE SUMMARY FOR JANUARY 11, 2021

 

Strong earthquakes hit the regions of Mongolia and Siberia (M 6.7) and northern Hokkaido, Japan (M 6.0) today. The earthquake in Hokkaido was reported by NEIC with intensity III in Hokodate, Hokkaido and Misawa, Aomori, Japan.

The last earthquake of M>=5.9 within about 200 km of today's event in the eastern Sea of Japan was an M 7.7 on July 12, 1993.  Forecast 130059 had expected today's event about 200 km to the east of today's epicenter was likely around January 9, 2021. This earthquake may have been promoted by tidal stresses associated with the new moon of January 13. It occurred within about 15 minutes of local solar noon, a time when tidal stresses are maximized as noted in this and previous issues of this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-11, 2021)

 

O: 12JAN2021 02:39:41  43.7N  140.1E Mw=6.0  EMSC   HOKKAIDO, JAPAN REGION       

O: 12JAN2021 02:39:42  43.7N  140.0E mw=6.0  ANSS   Eastern Sea of Japan        

P:  9JAN2021 130059    43.0N  142.0E 3.5-5.8 BABAA  Hokkaido, Japan            

 

The M 6.7 in Mongolia was widely felt in that area and in Siberia, Russia. The mainshock of M 6.7 was reported with minor damage in Moron, Hovsgol, Mongolia and IV in Shelekhov, Irkutsk, Erzin, Gusinoozyorsk, Burjatya, Russia and in Mongolia at Suhbaatar, Erdenet, and III in Usolye-Sibirskoye, Cheremkho, Angarsk, Irkutsk, Russia. Aftershocks of M 4.8 and M 5.0 were felt in Irkutsk, Russia (IV) and in Zuunharaa, Selenge, Mongolia (V). The mainshock occurred as the strongest geomagnetic storm in two months reached maximum at 21:00 UT as noted in this and previous issues of this summary as:

 

"The geomagnetic field saw active conditions today. The AP level was 14.  High latitude geomagnetic field also saw minor storm conditions with AP 20. This is the strongest disturbance in the geomagnetic field since in more than a month - since AP index reached  27 on November 27, 2020. Geomagnetic storms such as this can bring increases seismicity at high latitudes and near the geomagnetic equator over the next several days." (January 11, 2020)

 

and

 

"The maximum disturbance in the geomagnetic field today occurred with KP 4 at 21:00, January  11, 2021." (January 11, 2021)

 

Today's event of M 6.7 is the strongest in the world in two weeks - since an M 6.7 in Los Lagos, Chile on December 27, 2020. The only earthquake within about 300 km of this epicenter of equal or larger magnitude in this region near the Russia-Mongolia border was an M 6.7 about 300 km to the west on February 26, 2012 - the only such event in this region in the past 30 years. This epicenter is at the seventh node (52 degrees) from both the Dodecanese Islands of October 30, 2020 and from the M 7.6 in the Alaska Peninsula of October 19, 2020. It is also located in the antipodal area of the M 6.7 in Los Lagos, Chile of December 27, 2020. It was probably promoted by energy from these sources. One of the strongest earthquakes in this area in recent times occurred as an M 7.5 on January 12, 1862 exactly 159 years ago. This is detailed in the "HISTORY" section of this report.

 

O: 11JAN2021 22:22:44  51.2N  100.3E mb=4.5  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 11JAN2021 22:44:24  51.2N  100.3E mb=4.4  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 11JAN2021 22:02:56  51.3N  100.4E mb=5.0  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 00:36:10  51.3N  100.3E mb=4.8  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 11JAN2021 21:53:00  51.4N  100.3E mb=5.2  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 11JAN2021 23:02:23  51.4N  100.4E mb=5.0  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 00:34:05  51.4N  100.1E mb=4.5  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 00:27:11  51.5N  100.4E mb=4.0  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 00:31:40  51.5N  100.5E mb=4.2  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 01:49:53  51.5N  100.2E mb=4.7  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 11JAN2021 23:13:35  51.6N  100.3E mb=4.6  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 12JAN2021 01:10:34  52.0N   99.9E mb=4.4  EMSC   RUSSIA-MONGOLIA BORDER REGION

O: 11JAN2021 21:32:58  51.2N  100.5E Mw=6.7  EMSC   RUSSIA-MONGOLIA BORDER REGION

P:  8JAN2021 130118    51.0N   98.0E 3.0-4.4 BABAA  So. Siberia                

P: 15JAN2021 130447    51.0N   98.0E 3.0-4.4 BABAA  So. Siberia                

 

An M 5.4 was also felt in the Azores Islands of Portugal today. NEIC reported it was felt with intensity VI in Horta, Azores. This event may have been promoted by strong tidal stresses associated with the upcoming new moon of January 13. It occurred near local solar noon, an hour when such stresses are maximized. The M 5.4 is the strongest earthquake in the Azores within about 300 km of this epicenter since an M 5.5 on August 30, 2017, the strongest in the region since an M 6.2 on July 9, 1998 and the second largest in the past 30 years. Forecast 130075 and 130348 had expected today's activity within about 150 km  was likely between January 9-12 with magnitude up to M 6.1.

 

O: 11JAN2021 19:05:05  38.8N   29.4W ML=3.4  EMSC   AZORES ISLANDS, PORTUGAL

O: 11JAN2021 21:48:51  38.8N   29.4W ML=3.4  EMSC   AZORES ISLANDS, PORTUGAL

O: 12JAN2021 04:06:02  38.9N   29.5W ML=3.8  EMSC   AZORES ISLANDS, PORTUGAL

O: 11JAN2021 12:47:01  38.8N   29.4W Mw=5.4  EMSC   AZORES ISLANDS, PORTUGAL     

P:  9JAN2021 130075    40.0N   30.0W 4.0-5.3 ABAAA  No. Mid-Atlantic Ridge     

P: 12JAN2021 130348    38.0N   32.0W 4.0-6.1 AABAA  No. Mid-Atlantic Ridge     

 

The strongest earthquake in the U.S. or Canada today was an M 5.1, followed by an M 4.2 aftershock in the Unimak Island area of Alaska west of the Alaska Peninsula. The only earthquake in the Unimak Island area of equal or greater magnitude than M 5.1 occurred on August 13, 2020 with M 5.6. Forecast 130439 had expected today's event was likely around January 12.

 

O: 11JAN2021 07:19:04  53.8N  164.1W Mw=5.1  EMSC   UNIMAK ISLAND REGION, ALASKA 

O: 11JAN2021 10:44:56  53.8N  164.0W mb=4.2  EMSC   UNIMAK ISLAND REGION, ALASKA

P: 12JAN2021 130439    53.5N  165.8W 3.5-5.1 AAAAA  Fox Islands, Aleutians     

 

QUAKES AROUND NEW ZEALAND MAY INDICATE UPCOMING GLOBAL SEISMIC ENHANCEMENT

 

EARTHQUAKE SUMMARY FOR JANUARY 10, 2021

 

Earthquakes of M 5.5 each hit two oceanic ridge areas today - in the Southern East Pacific Rise and in the Balleny Islands south of New Zealand. These were not reported felt in these remote areas. The earthquake in the southern East Pacific Rise is the strongest within about 250 km of that epicenter since an M 5.7 on May 14, 2020 and prior to that an M 5.8 on September 27, 2019. Forecast 130183 had expected enhanced activity in this area was likely in early January, 2021. This earthquake is at 143 degrees of the Dodecanese quake of October 30, 2020 and may have been promoted by energy from that source.

 

O: 10JAN2021 15:44:47  35.4S  105.9W Mw=5.5  EMSC   SOUTHERN EAST PACIFIC RISE   

P: 01JAN2021 130183    36.0S  097.0W 4.0-5.4 AAAAA  Chile Rise                 

 

An earthquake of M 4.5 occurred near the antipode of the M 5.5 in the East Pacific Rise about 30 minutes prior to that event and may have been related to it through external forces. Forecast 130336 had expected today's event wasl likely within about 100 km of this epicenter around January 12.

 

O: 10JAN2021 15:14:41  36.6N   70.9E mb=4.5  EMSC   HINDU KUSH REGION, AFGHANISTAN

P: 12JAN2021 130336    36.0N   72.0E 3.8-5.2 AAAAA  Hindu Kush/Pakistan        

 

The M 5.5 south of New Zealand in the Balleny Islands was also located at an unusual epicenter. The last earthquakes within about 300 km of this epicenter in the Balleny Islands with M>=5.5 occurred in 2016 on January 31 (M 6.0) and June 15 (M 5.6). Today's event followed a series of unusual moderate earthquakes west of New Zealand.  Events in this region often precede strong enhancement in global seismicity, especially in the area of the coast of South America as detailed in this summary several days prior to the last strong earthquake in the world - the M 6.7 in Los Lagos, Chile as:

 

 

"An unusual earthquake occurred northwest of New Zealand today with M 4.8.  This is the strongest earthquake within about 300 km of this epicenter in at least 30 years. Previous earthquakes in this region have often  occurred within hours or days of strong earthquakes in southern Chile as discussed in this summary on February 24-25, 2010, ten years ago, several days before an M 8.8 in Central Chile" (December 26-27, 2020)

 

Some of today's activity may be related to strong tidal stresses related to the upcoming new moon as noted in previous issues of this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 8-10, 2021)

 

O: 11JAN2021 04:45:42  63.3S  170.8E mb=5.5  EMSC   BALLENY ISLANDS REGION       

 

Much of today's unusual activity occurred at the very deep focus of 750 depth within a limited time. This included strong deep focus earthquakes of M 5.6 in the Flores Sea, the largest in the world today, as well as both events west of New Zealand and a smaller quake in Mendoza, Argentina.  An external stressor may have been enabling of this activity.

 

O: 11JAN2021 01:20:38   7.2S  120.4E Mw=5.6  EMSC   FLORES SEA                   

O: 11JAN2021 01:38:47   7.3S  120.7E mb=4.8  EMSC   FLORES SEA

P: 10JAN2021 129902     8.0S  121.0E 4.0-5.6 AAAAA  Flores Island area         

 

An M 4.8 northwest of New Zealand is the strongest within about 250 km in this region in the past 30 years. It was not felt in the area. Forecast 130207 had expected regional activity would be enhanced around January 9.

 

O: 11JAN2021 01:28:03  38.5S  170.9E ML=4.8  EMSC   NORTHWEST OF NEW ZEALAND     

O: 11JAN2021 01:46:01  40.0S  168.3E ML=4.0  EMSC   OFF W. COAST OF S. ISLAND, N.Z

P:  9JAN2021 130207    43.0S  171.0E 3.0-5.2 ACBAA  So. Island, N.Z.           

 

O: 11JAN2021 00:45:26  36.7S  177.5E ML=3.5  EMSC   OFF E. COAST OF N. ISLAND, N.Z

P: 12JAN2021 130512    38.0S  179.0E 3.0-4.7 ABAAA  North Island, N.Z.         

 

The strongest earthquake in the U.S. or Canada today was an M 3.9 in the Alaska Peninsula. This epicenter is southeast of the aftershock zone of the October 19, 2020. M 7.6 in a somewhat unusual region of the Alaska Peninsula. The last earthquake within about 150 km of this epicenter with larger magnitude was an M 4.1 on October 19, 2020, in concert with the M 7.6 mainshock on that date. An M 4.1 hit the area two days before this on October 17, 2020 and may have been precursory to the M 7.6. Forecast 130430 had expected activity southwest of this around January 13.

 

 

O: 10JAN2021 13:17:35  57.0N  155.5W mb=3.9  EMSC   ALASKA PENINSULA              

P: 13JAN2021 130430    54.8N  158.7W 3.5-4.9 BCBAA  Alaska Peninsula           

 

The current swarm in Southern California near the Baja border continued today and included an M 3.3. This event occurred near local solar midnight and may have been enhanced by tidal stresses which maximize at this hour. This swarm restarted on January 4, 2021 with an M 4.0. Forecast 130359 had expected this activity around January 15.

 

NEIC reported these earthquakes of M 3.2 and M 2.7 in Southern California were felt with intensity II-III in the area(s) of Southern California in Calipatria, Westmorland, La Quinta and San Diego.

 

O: 10JAN2021 21:28:45  32.8N  115.8W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 07:01:48  33.2N  115.6W ML=2.8  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 07:59:01  33.2N  115.6W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 08:21:03  33.2N  115.6W ML=3.3  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 08:23:46  33.2N  115.6W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 08:53:56  33.2N  115.6W ML=2.1  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 08:53:56  33.2N  115.6W ML=2.1  EMSC   SOUTHERN CALIFORNIA

O: 10JAN2021 08:02:15  33.3N  115.5W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 11JAN2021 04:58:37  32.7N  115.8W Ml=2.2  EMSC   SOUTHERN CALIFORNIA           

P: 15JAN2021 130359    32.8N  115.4W 2.5-4.6 BAAAA  So. California             

 

RONG EARTHQUAKES IN VANUATU AND NORTHERN CHILE

 

EARTHQUAKE SUMMARY FOR JANUARY  9, 2021

 

Strong earthquakes in Vanuatu (M 6.1) and northern Argentina (M 6.1) continued seismic enhancement in those areas today. The earthquake of M 6.0-6.1 in Vanuatu was reported by NEIC to have been felt with intensity III in Luganville, Sanma, Vanuatu. The last earthquake within about 200 km of this epicenter in central Vanuatu with M>6.0 occurred with M 6.2 on September 6, 2020 with M 6.2 and prior to that as an M 6.4 on August 5, 2020. Forecasts 130161 and 130491 had expected today's activity within about 15 km was likely around January 8-12. This activity is near 103 degrees from the M 6.7 in Los Lagos of December 29, 2020 and was probably promoted by energy from that source.

 

O: 10JAN2021 06:48:20  16.1S  167.9E Mw=6.0  EMSC   VANUATU                      

P:  8JAN2021 130161    16.0S  168.0E 4.0-5.6 AAAAA  Vanuatu Islands            

P: 12JAN2021 130491    16.0S  168.0E 4.0-5.5 AAAAA  Vanuatu Islands            

 

The M 6.1 in northern Argentina was reported by NEIC to have been felt with intensity VI in Salta, Argentina; IV in Antofagasta, Chile and II in Iquique, Tarapaca, Chile. It was preceded by an M 4.5 foreshock that was felt with intensity III in Antofagasta. GUC reported this earthquake was felt with intensity  IV in  Antofagasta at Antofagasta, Calams, Mejillones and III in Taltal, Tocopilla; in Tarapaca with III in Iquique and II in El Loa, La Tirana, Pica, Pozo Almonte; and in Atacama with IV in Chararal, Diego de Almagro, El Salvador and III in Copiapo and Tierra Amarillo, Chile. This is the strongest earthquake within about 250 km of this epicenter since an M 6.3 on November 20, 2020 and prior to that an M 6.3 on April 15, 2017. Forecasts 130163 and 130165 had expected today's event was likely in early January. The quake occurred within about 30 minutes of local solar midnight and may have been enhanced by strong tidal stresses which are maximized at this hour. Maximum stress with the next full moon on January 13 is near this longitude as noted in the tidal forecast for that alignment in this summary:

 

"The new moon will arrive at 05:00 UT on January 13. Longitudes which are at sub-lunar conditions (local solar midnight) at this time are near 75 West and those at sub-solar conditions (local solar noon) are near 105 East. These include in the west, the west coast of South America and eastern North America and in the east western and central Indonesia, the Philippines and Taiwan among others. These areas are most likely to see tidally enhanced seismicity in the next week through January 17, 2021. Tidal enhancement is most likely near local solar noon and midnight. A strong global earthquake is likely in this period." (January 9-10, 2021)

 

O: 10JAN2021 03:54:10  24.0S   66.7W Mw=6.1  EMSC   JUJUY, ARGENTINA             

O: 10JAN2021 03:54     24.0S   67.1W mb=5.9  GUC    Antofagasta at Antofagasta, Ca

P:  5JAN2021 130163    24.0S   67.0W 4.0-5.8 BAAAA  Argentina                  

P:  9JAN2021 130165    24.0S   69.0W 4.0-5.8 AABAA  Coast No. Chile            

 

Strongly felt earthquakes continued to be felt in the region of Zagreb, Croatia today. An M 4.8 was reported (NEIC) felt with intensity IV in Croatia at Sisak, Kulina, and II-III in Kuce, Gradici, Nicevec, Cazma, Ilova, Kozinscak and Kupinec and in Bosnia and Herzegovina. This is aftershock activity of the M 6.4 of December 29, 2020. Forecast 130051 had expected today's activity was likely around January 6.

 

O:  9JAN2021 21:29:09  45.4N   16.4E ML=4.5  EMSC   CROATIA                      

P:  6JAN2021 130051    45.0N   16.0E 3.0-5.2 BAAAA  Adriatic Sea               

 

An unusual earthquake of M 4.8 occurred today in the State of Chuuk, Micronesia. It was not reported felt in this remote area. The last earthquake of M>=4.8 within about 300 km of this epicenter occurred 10 years ago on November 26, 2011 after an M 5.7 on November 9, 2011. The only quake within 200 km of today's event at this magnitude was an M 4.8 about 150 km northwest on October 1, 1994. Forecast 130294 had expected enhanced regional seismicity around January 12, 2021.

 

O:  9JAN2021 15:00:57   9.7N  148.1E mb=4.8  EMSC   STATE OF CHUUK, MICRONESIA   

P: 12JAN2021 130294    12.0N  144.0E 4.0-5.5 BCCAA  So. Marianas/Guam          

 

The strongest earthquake in the U.S. or Canada today was an M 4.6 in the eastern Rat Islands, Aleutians, Alaska. An M 4.6 hit this area of the Rat Islands on January 6, 2021 but the last event of larger magnitude in the Rat Islands was an M 4.9 on September 24, 2020. Forecasts 130116 and 130445 had expected this event within about 50 km in early to mid-January, 2021.

 

O: 10JAN2021 02:44:36  51.9N  178.6E mb=4.6  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P:  4JAN2021 130116    50.0N  178.0E 4.0-5.7 CBAAA  Rat Islands                 

P: 15JAN2021 130445    52.0N  178.0E 4.0-5.6 BAAAA  Rat Islands                

 

STRONG SEISMIC ENHANCEMENT CONTINUES IN SOUTHWESTERN PACIFIC AREA

 

EARTHQUAKE SUMMARY FOR JANUARY  7, 2021

 

Seismicity in the Southwestern Pacific near the geomagnetic equator continued

today with events of M 6.1 in Vanuatu and M 6.3 in the northern Kermadec Islands of New Zealand. The earthquake in the northern Kermadec Islands is part of an activation of the region which began on January 6, 2021 with an M 6.2. This was expected to continue as noted in the previous issue of this summary:

 

"Two earthquakes of M 4.9 each were recorded in the northern Kermadec Islands, of New Zealand today. They were not reported felt in this remote area. These appear to be aftershocks of the M 6.2 that hit the area yesterday. Strong earthquakes in the northern Kermadec Islands tend to occur in clusters and more of this activity is expected in the next several days." (January 6-7, 2021)

 

and

 

"The largest earthquake in the world today was an M 6.2 in the northern Kermadec Islands, New Zealand. It was not reported felt in this remote area. This is the strongest earthquake in the northern Kermadec Islands within about 200 km of this epicenter since an M 6.2  on June 21, 2019, an event which followed an M 7.2 about 300 km southwest of today's epicenter which occurred on June 15, 2019. Forecasts 130187 and 130167 had expected today's activity between January 6 and 9, 2021 was likely within about 10 km of today's epicenter." (January 5-6, 2021) 

 

Forecast 130187 had expected today's event of M 6.3 was likely within about 100 km of this epicenter around January 6.

 

O:  8JAN2021 00:28:44  29.5S  178.8W Mw=6.3  EMSC   KERMADEC ISLANDS, NEW ZEALAND

P:  6JAN2021 130187    30.0S  178.0W 4.0-5.4 AAAAA  No. Kermadec Islands       

 

The M 6.1 in Southern Vanuatu was reported felt with intensity IV in New Caledonia at Tadine and III in Noumea. This is the strongest earthquake in southern Vanuatu within about 200 km of this epicenter since an M 6.4 more than a year ago on October 21, 2019. Forecast 130166 had expected today's event within about 100 km was likely around January 4, 2021.

 

O:  8JAN2021 05:01:04  20.7S  169.9E Mw=6.1  EMSC   VANUATU                      

P:  4JAN2021 130166    21.0S  169.0E 4.0-5.5 BAAAA  Loyalty Islands            

 

An unusual earthquake, the largest in the U.S. or Canada today, of M 4.7 occurred off the east coast of New York in the North Atlantic today. The only earthquake within about 250 km of this epicenter in the past 30 years of M>=3.5 occurred as an M 4.2 on March 18, 2007. Today's event is the strongest in the area in at least three decades.

 

O:  6JAN2021 11:02:12  40.3N   53.7W MB=4.7  ECAN North Atlantic Ocean           

 

An aftershock of M 4.4 also occurred in the aftershock zone of the Alaska Peninsula following the M 7.6 of October 19, 2020. This is the strongest aftershock in this area since an M 4.5 on December 30, 2020. Forecast 130100 had expected this activity was likely around January 7, 2021.

 

O:  7JAN2021 15:51:31  54.6N  159.8W ML=3.0  EMSC   SOUTH OF ALASKA              

O:  8JAN2021 01:59:22  54.7N  159.7W mb=4.4  EMSC   SOUTH OF ALASKA              

P:  7JAN2021 130100    54.8N  158.7W 3.5-4.9 AAAAA  Alaska Peninsula           

 

GLOBAL SEISMICITY TURNS ACTIVE

 

EARTHQUAKE SUMMARY FOR JANUARY  6, 2021

 

It was an active in global seismicity. The largest earthquakes in the world occurred in New Guinea and Indonesia with the strongest of these an M 6.1 in the Minahassa, Sulawesi, Indonesia. Moderately strong earthquakes also were registered in Papua New Guinea west of the Solomon Islands (M 5.8) and Southern Sumatra, Indonesia (M 5.5). This activity may have been enhanced by effects from the current geomagnetic storm as most of it is located near the geomagnetic equator. For further details on this storm see the External Effects section of this and previous report.

 

The M 6.1 in Sulawesi, Indonesia was reported with intensity II at Gorontalo and in Luwuk, Sulawesi, Indonesia by NEIC. BMG reported this earthquake with M 6.5 was felt throughout the area of Sulawesi with intensity III-V. An M 6.1 hit within about 100 km of this epicenter on January 19, 2020 but the last of larger magnitude within about 200 km was an M 7.4 on November 16, 2008 about 200 km northwest of today's epicenter. Forecasts 129882 and 129919 had expected today's activity within about 100 km was likely in early January.

 

O:  6JAN2021 20:59:35   0.0N  122.9E Mw=6.1  EMSC   MINAHASA, SULAWESI, INDONESIA

P:  3JAN2021 129882     0.0N  122.0E 4.0-5.4 BAAAA  Celebes Sea                

P:  8JAN2021 129919     1.0S  122.0E 4.0-5.4 AAAAA  Sulawesi area              

P:  8JAN2021 129919     1.0S  124.0E 4.0-5.4 AAAAA  Sulawesi area              

 

The M 5.5 in southern Sumatra was reported by NEIC to have been felt with intensity IV in Bengkulu, Indonesia. BMG reported this event at M 5.8 and noted it was felt with intensity IV-V in Southern Sumatra. This event is the strongest within about 200 km of this epicenter since a pair of events of M 6.8 and 6.9 on August 18, 2020. Forecast 129917 had expected today's event was likely in this area around January 6, 2021.

 

O:  6JAN2021 17:28:35   4.3S  102.7E Mw=5.5  EMSC   SOUTHERN SUMATRA, INDONESIA  

P:  5JAN2021 129917     6.0S  103.0E 4.0-5.3 ABAAA  So. of Sumatera            

 

An earthquake of M 4.6 followed the earthquake in Sumatra near the antipode in northern Colombia and may have been enhanced by energy from Sumatra. Forecast 129886 expected the Colombia quake within about 20 km of this epicenter was likely around January 10.

 

O:  7JAN2021 04:37:36   6.8N   73.0W mb=4.6  EMSC   NORTHERN COLOMBIA            

P: 10JAN2021 129886     7.0N   73.0W 4.0-5.4 BAAAA  Colombia                   

 

NEIC reported the M 5.8 in the Solomon Islands was felt with intensity III in Gizo, Western Solomon Islands. The last event in the Solomon Islands within about 200 km of today's epicenter of M>=5.8 was an M 6.3 on April 25, 2020 and before that an M 6.2 on January 26, 2019. Forecast 129918 had expected today's event within about 25 km of the epicenter was likely around January 5, 2021.

 

O:  6JAN2021 16:52:12   7.0S  155.7E mb=5.8  EMSC   BOUGAINVILLE REGION, P.N.G.  

P:  5JAN2021 129918     7.0S  156.0E 4.0-5.4 AAAAA  Solomon Islands             

 

Two earthquakes of M 4.9 each were recorded in the northern Kermadec Islands, of New Zealand today. They were not reported felt in this remote area. These appear to be aftershocks of the M 6.2 that hit the area yesterday. Strong earthquakes in the northern Kermadec Islands tend to occur in clusters and more of this activity is expected in the next several days. Forecast 130167 had expected today's activity within about 15 km of these epicenter was likely around January 6.

 

O: 06JAN2021 16:17:44  29.1S  176.9W mb=4.9  EMSC   KERMADEC ISLANDS REGION

O:  6JAN2021 18:18:37  28.6S  177.6W mb=4.9  EMSC   KERMADEC ISLANDS REGION      

P:  9JAN2021 130167    29.0S  177.0W 4.0-5.4 BAAAA  No. Kermadec Islands       

 

The strongest aftershock to date of the M 6.4 in Croatia of December 29, 2020 was also recorded with M 5.0 and was widely felt with damage at intensity VIII in Croatia at Petrinja and IV in Gvozo, Gradici, Lupoglav, Zagreb, Lupogia, Kozinscak, and Adamovec and II-III in Micevec, Sesvete and Velika Gorica. This is the strongest aftershock to date of the M 6.4 on December 29, 2020. Five earthquake of M>=5 have occurred in Croatia in the past 30 years all with M<5.5 Forecast 130051 had expected enhanced seismicity in Croatia around January 6.

 

O:  6JAN2021 17:01:43  45.4N   16.3E mb=5.0  EMSC   CROATIA                      

P:  6JAN2021 130051    45.0N   16.0E 3.0-5.2 AAAAA  Adriatic Sea               

 

A pair of light earthquakes of M 2.4 and 3.2 occurred in the Yellowstone National Park, Wyoming today. The M 3.2 is the strongest located in the Yellowstone area since an M 3.4 on December 15, 2019 more than a year ago and prior to that an M 3.5 on August 15, 2019. Forecast 130098 had expected this activity was likely around January 4, 2021.

 

O: 06JAN2021 16:27:09  44.7N  110.7W Ml=2.4  EMSC   YELLOWSTONE NAT. PARK, WYOMING

O:  6JAN2021 15:38:33  44.7N  110.7W ML=3.2  ANSS   YELLOWSTONE NAT. PARK, WYOMING

P:  4JAN2021 130098    44.6N  110.8W 2.0-3.9 AAAAA  Yellowstone/Wyoming        

 

STRONG M 6.2 IN KERMADEC ISLANDS, NEW ZEALAND

 

EARTHQUAKE SUMMARY FOR JANUARY  5, 2021

 

The largest earthquake in the world today was an M 6.2 in the northern Kermadec Islands, New Zealand. It was not reported felt in this remote area. This is the strongest earthquake in the northern Kermadec Islands within about 200 km of this epicenter since an M 6.2  on June 21, 2019, an event which followed an M 7.2 about 300 km southwest of today's epicenter which occurred on June 15, 2019. Forecasts 130187 and 130167 had expected today's activity between January 6 and 9, 2021 was likely within about 10 km of today's epicenter. 

 

O:  6JAN2021 06:20:35  29.1S  177.1W Mw=6.2  EMSC   KERMADEC ISLANDS, NEW ZEALAND

P:  6JAN2021 130187    30.0S  178.0W 4.0-5.4 AAAAA  No. Kermadec Islands       

P:  9JAN2021 130167    29.0S  177.0W 4.0-5.4 BAAAA  No. Kermadec Islands       

 

The strongest earthquake in the U.S. or Canada today was an M 4.6 in the Rat Islands, Aleutians, Alaska. NEIC did not report this as felt. This is the strongest earthquake in the Rat Islands within about 200 km of this epicenter since an M 4.6 on August 27, 2020. The last event in the region of M>=5 was an M 5.3 on February 4, 2020. Forecast 130116 expected today's event within about 100 km was likely around January 4.

 

O:  6JAN2021 00:25:49  51.2N  178.9E mb=4.6  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P:  4JAN2021 130116    50.0N  178.0E 4.0-5.7 ABAAA  Rat Islands                

 

Moderate earthquakes occurred today in the eastern Caribbean in Antigua and Barbuda (M 4.3) and in the Gulf of Paria, Venezuela (M 4.5). The last event of M>=4.3 in Antigua was an M 4.3 on May 16 and March 31, 2020 - both with M 4.3. The last earthquake of larger magnitude in Antigua was an M 4.5 on November 10, 2018. Forecast 129936 had expected today's activity around January 8. 

 

O:  5JAN2021 07:39:40  17.8N   61.5W mb=4.3  EMSC   ANTIGUA AND BARBUDA REGION   

P:  8JAN2021 129936    17.0N   60.0W 3.0-4.9 BABAA  Leeward Islands            

 

The last earthquake of M>=4.5 in the Gulf of Paria, Venezuela region was an M 4.6 on July 27, 2020 and before that an M 4.7 on March 16, 2020. Forecast 129958 had expected today's event within about 100 km was likely around January 7.

 

O:  6JAN2021 02:35:44  10.5N   62.6W mb=4.5  EMSC   GULF OF PARIA, VENEZUELA     

P:  7JAN2021 129958    11.0N   62.0W 3.4-4.8 AAAAA  Windward Islands           

 

M 5.6 IN SOUTH SANDWICH ISLANDS FOLLOWS STRONG GRB

 

EARTHQUAKE SUMMARY FOR JANUARY  4, 2021

 

The strongest earthquake in the world today was an M 5.6 in the South Sandwich Islands. It was not reported felt in that remote area. This is the strongest earthquake within about 200 km in the South Sandwich Islands since an M 6.1 on November 2, 2019. It occurred within about an hour of local solar noon, a time when tidal stresses maximize and may have been enhanced by these. It also occurred about 50 minutes of a strong Gamma Ray Burst (GRB) as noted below:

 

"The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on January  04, 2021 at 11:26 UT with BAT Fluence n/a     erg/sqcm. (MAGNITUDE: > 16.3), Associated earthquake: M 5.6 South Sandwich Islands 12:16 UT 01-04-2021)" (January 4-5, 2021)

 

Forecast 130219 had expected today's event within about 150 of this epicenter was likely around January 7. This earthquake is located at 103-105 degrees from the M 7.0 in the Dodecanese Islands of October 30, 2020, the last major global earthquake. It was probably promoted by energy from that source. Other earthquakes today at this distance from the Dodecanese Islands included a strong swarm in southern Califoria including events of M 3.5 and 3.7; as well as an M 4.9 in Panama and moderate quakes in Guatemala and Bolivia.

 

O:  4JAN2021 12:16:14  57.1S   26.9W Mw=5.6  EMSC   SOUTH SANDWICH ISLANDS REGION

P:  7JAN2021 130219    58.0S   25.0W 4.0-6.0 BAAAA  So. Sandwich Islands       

 

An unusual earthquake of M 3.1 was widely felt in the area of South Dakota south of Mitchell today. NEIC reported intensity II-III in South Dakota at Tyndall, Scotland, Avon, Tabor, Springfield, Menno, Yankton, and ne Nebraska at Niobrara and Croften and in Sioux City, Iowa. The is the strongest earthquake in South Dakota or Nebraska within about 200 km of this epicenter since an  M 4.3 on November 3, 2002. That event had been noted in this summary on November 3, 2002 as possibly precursory to strong activity in the western U.S. as:

 

"The Alaskan earthquake today (M 7.9) was preceded by a Ml 4.3 event about an hour and a half prior in eastern Nebraska. Two earthquakes occurred in Kansas on  November 1 (Ml 3.0, 2.8). Such earthquakes often precede great earthquakes in Alaska and other areas on the borders of North America.  The resemblance of this great plains foreshock series to that which preceded the great  Alaska earthquake of March, 1964 is uncanny, if there is no causative  relation. In 1964 a Ml 4.3 earthquake was felt along the South Dakota/Nebraska border about 30 minutes before the Great quake in Alaska, one of the largest ever recorded in this region. This had been preceded by smaller earthquake in the same region on March 24 and 27. Today's Nebraska earthquake occurred 1.5 hours before the great Alaska event and had been preceded by the Kansas earthquakes by two days.  Since all of these are unusual events, their coincidence in time (in more than one occasion) may be significant." (November 3-4, 2002)

 

Today’s South Dakota event followed the GRB by several hours and may have been promoted by effects from that event.

 

O:  4JAN2021 14:55:45  43.1N   97.8W mb=3.1  EMSC   SOUTH DAKOTA                 

 

A pair of moderate earthquakes occurred in northern Europe today. These unfelt quakes of M 4.6 and 4.7 occurred in northern Iceland and in the Greenland Sea.

The earthquake in Iceland is the strongest within about 150 km of that epicenter since an M 4.9 on March 26, 2017.  Forecast 130133 had expected this event to the southeast was likely around January 3.

 

O:  4JAN2021 08:37:47  67.8N   19.1W mb=4.7  EMSC   ICELAND REGION               

P:  3JAN2021 130133    65.0N   16.0W 3.0-4.4 ACBAA  Iceland area               

 

The M 4.6-4.8 in the Greenland Sea is the strongest within about 150 km of that epicenter since an M 4.6 on October 17, 2020. Forecast 130140 had expected today's event was likely around January 7. This, and the event near Iceland are located at the 7th node (52 degrees) from the Alaska Peninsula M 7.6 of October 19, 2020 and may have been promoted by energy from that source.

 

O:  4JAN2021 14:38:51  73.1N    6.8E mb=4.6  EMSC   GREENLAND SEA                

O:  4JAN2021 14:38:51  73.1N    6.3E mb=4.8  ANSS   GREENLAND SEA                

P:  7JAN2021 130140    72.0N    0.0E 3.0-4.6 BBAAA  Norway                     

 

The strongest earthquake in the U.S. or Canada today was an M 3.8 ini the Northwest Territories of Canada. It was not reported felt by NEIC. The last earthquake of M>=3.8 within about 150 km of this epicenter was an M 4.4 on November 17, 2020. A series of moderate quakes occurred in this area beginning on July 25, 2020 and ending with an M 4.7 on October 24, 2020 and today's event may be an aftershock of those events. Forecast 130135 had expected today's event within about 25 km around January 4.

 

O:  5JAN2021 02:35:51  62.2N  124.5W ML=3.8  EMSC   NORTHWEST TERRITORIES, CANADA

P:  4JAN2021 130135    62.1N  124.2W 2.5-4.2 AAAAA  Northwest Terr., Canada    

 

Moderate earthquakes also continued to be felt in Croatia today. The strongest events in the area today were an M 4.5 and 3.5 and were aftershocks of the M 6.4 of December 29, 2020. NEIC reported this earthquake of M 3.5-4.0  in Croatia  was felt with intensity II-III in the area(s) of  Croatia at Zagreb. An earlier M 4.4-4.5 in Zabreb, Croatia was reported felt with intensity IV in Gvozd and II-III in Zabreb, Husain and in Trieste, Italy. Forecast 130051 had expected today's activity was likely around January 6.

 

O:  4JAN2021 18:28:57  45.4N   16.3E ML=3.5  EMSC   CROATIA                      

O:  4JAN2021 06:49:53  45.4N   16.2E ML=4.5  EMSC   CROATIA                      

P:  6JAN2021 130051    45.0N   16.0E 3.0-5.2 AAAAA  Adriatic Sea               

 

An earthquake of M 3.2 in the Canary Islands today was the strongest in the

current series in that area. An M 3.2 last occurred in the Canary Islands on December 31, 2020. Forecast 129961 had expected today's event was likely around January 4.

 

O:  5JAN2021 05:00:08  29.3N   14.5W ML=3.2  EMSC   CANARY ISLANDS, SPAIN REGION 

P:  4JAN2021 129961    28.0N   16.0W 3.0-4.6 ABBAA  Canary Islands             

 

STRONG EARTHQUAKE M 6.1 IN WESTERN ANDREANOF ISLANDS, ALEUTIANS, ALASKA

 

EARTHQUAKE SUMMARY FOR JANUARY  3, 2021

 

The strongest earthquake in the world today was an M 6.1 in the western Andreanof Islands, Alaska. NEIC reported it was felt with intensity III in Adak.

This follows a series of moderate events near the antipode which occurred southwest of Africa in the southern Atlantic over the past two days and a strong GRB near local solar noon. This summary had expected in previous issues that this could enhance seismicity in this area of the Rat and Andreanof Islands as:

 

 

"This activity may help enhance further activity in the eastern Rat Islands and the western Andreanof Islands in the next several days. As noted above these are at the antipode of the quakes in the South Atlantic. The last such quakes in this area of the Atlantic with M>=5.1 occurred on August 28, 2020 (M 5.8) and August 14, 2019 (M 5.2)." (January 2-3, 2021)

 

and prior to that on January 1, 2021 as:

 

 

"The strongest earthquakes in the world today were of M 5.1-5.2. One of these was an M 5.2 in the Southern Mid-Atlantic near the antipode of the Rat Islands, Alaska. It occurred several hours after an M 4.3 at the Rat Islands antipode but was probably not related to that event, the strongest in the Rat Islands since N 4.9 on September 24. Today's event occurred within about 15 minutes of local solar midnight in the South Atlantic and was likely promoted by strong tidal effects related to the full moon of December 30." (January 1, 2021)

 

Today's event occurred within about 30 minutes of local solar midnight  and may have been enhanced by tidal stresses which maximize near this hour. This is the strongest earthquake in the western Andreanof Islands in nearly a year - since an M 6.1 on January 26, 2020 and the strongest in the region of the astern Rat Islands since an M 6.4 on April 2, 2019.

 

This event in Alaska followed a strong Gamma Ray Burst - the first of 2020 - which occurred near local solar noon in Alaska (#210102C). Details are:

 

The last major Gamma Ray Burst (GRB) according to the online NASA Swift GRB Catalog was observed on January  02, 2021 at 20:38 UT with BAT Fluence 39X10-7 erg/sqcm. (MAGNITUDE: n/a ), Associated earthquake: M 6.1 Andreanof Islands 12:38 UT 01-03-2021)

 

O:  3JAN2021 12:38:49  51.3N  179.8W Mw=6.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  4JAN2021 130103    51.7N  179.7W 3.5-5.1 AAAAA  Andreanoff Isls, Aleutians 

 

A moderate earthquake of M 4.9 preceded the Andreanof event in the Kodiak area of Alaska. NEIC reported it was felt with intensity III in Kodiak. This is the strongest earthquake in the Kodiak Island area of Alaska since an 5.1 on July 8, 2020 about 150 km to the south of today's epicenter. The last such event within about 100 km of this was an 4.9 two years ago on January 2, 2019. Forecast 130126 had expected today's event was likely around January 4.

 

O:  3JAN2021 08:45:02  57.6N  153.9W Mw=4.9  EMSC   KODIAK ISLAND REGION, ALASKA 

P:  4JAN2021 130126    60.0N  153.5W 3.2-5.1 ACAAA  Central Alaska              

 

UN

MODERATE QUAKES ON SOUTHERN OCEAN RIDGES

 

EARTHQUAKE SUMMARY FOR JANUARY  2, 2021

 

The strongest activity in the world today was a series of moderate earthquakes

on Ocean Ridges with M 5.0-5.4. These were located in the South Shetland Islands (M 5.2-5.4); the Central Mid-Atlantic (M 5.1); the South Atlantic south of Africa (M 5.1, 5.1); and the Indian Ocean south of Africa (M 5.1).

 

The strongest earthquake in the world today was an M 5.2-5.4 in the Magallanes and Antarctica, Southern Chile. GUC reported it was felt in Antarctica with intensity IV. This follows a series in the South Shetland which began in late October and has included an M 6.0 on November 6, 2020. The activity has died down in recent weeks with the last event of M>=5.4 in the area on November 6.

Forecast 130223 had expected today's event within about 50 km was likely around January 5, 2021. This activity is at the third node (120 degrees) from the M 7.0 in the Dodecanese Islands of October 30, 2020, the last major global earthquake.

 

O:  2JAN2021 23:21:20  62.4S   58.2W Mw=5.2  EMSC   SOUTH SHETLAND ISLANDS       

O:  2JAN2021 23:21     62.5S   58.6W mb=5.4  GUC    Magallanes and Antarctica.   

P:  5JAN2021 130223    62.0S   58.0W 4.0-5.8 BAAAA  Southern  Ocean            

 

The two earthquakes in the Atlantic south of Africa followed similar activity there in the past several days as noted in previous issues of this report:

 

"The strongest earthquakes in the world today were of M 5.1-5.2. One of these was an M 5.2 in the Southern Mid-Atlantic near the antipode of the Rat Islands, Alaska. It occurred several hours after an M 4.3 at the Rat Islands antipode but was probably not related to that event, the strongest in the Rat Islands since N 4.9 on September 24. Today's event occurred within about 15 minutes of local solar midnight in the South Atlantic and was likely promoted by strong tidal effects related to the full moon of December 30." (January 1, 2021)

 

This activity may help enhance further activity in the eastern Rat Islands and the western Andreanof Islands in the next several days. As noted above these are at the antipode of the quakes in the South Atlantic. The last such quakes in this area of the Atlantic with M>=5.1 occurred on August 28, 2020 (M 5.8) and August 14, 2019 (M 5.2). Forecast 129875 had expected today's activity was

likely around December 31, 2020.

 

O: 03JAN2021 03:27:17  52.1S    5.0W mb=5.1  EMSC   SOUTHERN MID-ATLANTIC RIDGE

O:  3JAN2021 03:21:42  52.1S    4.9W mb=5.1  EMSC   SOUTHERN MID-ATLANTIC RIDGE  

P: 31DEC2020 129875    55.0S    2.0E 4.0-5.3 ACBAA  Atlantic-Indian Ridge      

 

The earthquake of M 5.1 in the Indian Ocean south of Africa today is within about 100 km of the antipode of the last major earthquake in the world - the M 7.6 in the Alaska Peninsula of October 19, 2020. The last earthquakes of M>=5 within about 300 km of today's event occurred on October 19, 2020 with the Alaska Peninsula event of that date with M 5.0. The last within about 200 km was an M 5.4 on January 10, 2020 and prior to that on December 2, 2018 with M 5.4.

Forecast 130215 had expected enhanced activity in this area around January 9, 2021. This activity could enhance further aftershocks in the Alaska Peninsula or the eastern Fox Islands, Aleutians in the next several days.

 

O:  2JAN2021 09:23:39  53.0S   20.9E mb=5.1  EMSC   SOUTH OF AFRICA              

P:  9JAN2021 130214    53.0S   19.0E 4.0-5.3 AAAAA  Atlantic-Indian Ridge      

 

An M 5.2 in the Central Mid-Atlantic today may be a regional aftershock of the M 6.7 that hit that area on September 18, 2020. It was not reported felt in this remote area. Two moderate earthquakes (M 5.2, 4.7) in the New Britain region today were located near the antipode of the Mid-Atlantic event. Forecast 129883 had expected the Atlantic event within about 25 km was likely around January 7, while the events in New Britain were expected in forecast 129618 within about 10-75 km. The activity  in New Britain is at the third node (120 degrees) from the M 7.0 in the Dodecanese Islands of October 30, 2020, the last major global earthquake.

 

O:  3JAN2021 05:25:20   1.0N   28.2W mb=5.2  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P:  7JAN2021 129883     1.0N   28.0W 4.0-5.4 BAAAA  Central Mid-Atlantic Ridg  

 

O:  2JAN2021 16:36:33   5.1S  153.0E mb=4.7  EMSC   NEW BRITAIN REGION, P.N.G.   

O:  2JAN2021 08:34:18   5.7S  153.1E mb=5.2  EMSC   NEW IRELAND REGION, P.N.G.   

P:  1JAN2021 129618     5.0S  153.0E 4.0-5.3 AAAAA  New Britain                

 

Another near-antipodal event occurred on January 1, 2021 in Northern Qinghai, China. This is the strongest earthquake recorded in northern Qinghai since an M 4.7 on  March 24, 2020. The epicenter is within about 200 km of the antipode  of the M 6.7 in Los Lagos of December 27, 2020 (compare 37N and 39S and 75W and 95E) for antipodality. Forecast 130035 had expected regional enhancement around January 2.

 

O:  1JAN2021 20:24:35  37.0N   94.6E mb=4.5  EMSC   NORTHERN QINGHAI, CHINA      

P:  2JAN2021 130035    32.0N   95.0E 3.5-5.0 ACAAA  So. China                   

 

The strongest earthquake in the U.S. or Canada today occurred as an M 4.3 in Central California south of San Francisco. NEIC reported it was felt with maximum intensity IV in California at Soledad, Hollister, Paicines and II-III in Gonzales, Salinas, San Juan Bautista. A foreshock of M 3.2 six minutes before the M 4.3 was felt with intensity II-III at Soledad, Hollister, Salinas, Greenfield, Los Banos, Seaside, Monterey, Aptos, Capitola and Santa Cruz, California. Aftershocks of intensity II-III were felt at Los Banos, California; as an M 3.4 in Gonzales, Soledad, Paicines, Salinas, Carmel Valley, Los Banos, Marina and Watsonville, This earthquake occurred in the Creeping section of the San Andreas in California. Moderate earthquakes in this section can increase stress in the non-creeping sections of the Fault near San Francisco and bring larger quakes in that area. The last earthquakes within about 75 km of today's epicenter occurred as an M 4.7 on October 15, 2019; an M 4.6 on November 13, 2017 and an M 4.4 on January 20, 2015. Forecasts 129987 and 129988 had expected today's activity was likely around January 4-7 within about 25 km of today's mainshock. Following is a list of aftershocks in the area of M>2.5. A more complete listing can be found in the "CALIFORNIA" section of this summary. As noted in the previous issue of this summary Central California is near 103 degrees from the Dodecanese M 7.0 of October 30 as:

 

"This activity is located at 103 degrees from the Dodecanese Islands quake of

M 7.0 on October 30, 2020 and was probably promoted from that source.

Other earthquakes at this distance from Greece today occurred in Central

California, the Gulf of California, Baja California, Banda and Ceram, Indonesia, Costa Rica." (January 1-2, 2021)

 

Events of M 5.1 in New Guinea and in Guatemala today joined these at or near

103 degrees from Greece.

 

 

O: 02JAN2021 14:42:22  36.6N  121.2W Mw=4.3  EMSC   CENTRAL CALIFORNIA

O: 02JAN2021 15:08:42  36.6N  121.2W Md=2.6  EMSC   CENTRAL CALIFORNIA

O: 02JAN2021 15:41:29  36.6N  121.2W MD=2.7  EMSC   CENTRAL CALIFORNIA

O: 02JAN2021 21:31:41  36.6N  121.2W Md=2.7  EMSC   CENTRAL CALIFORNIA

O: 02JAN2021 23:34:32  36.6N  121.2W MD=2.8  EMSC   CENTRAL CALIFORNIA

O: 03JAN2021 02:45:39  36.6N  121.2W Md=2.6  EMSC   CENTRAL CALIFORNIA

O: 03JAN2021 03:51:09  36.6N  121.2W Ml=3.1  EMSC   CENTRAL CALIFORNIA

O: 03JAN2021 05:21:59  36.6N  121.2W Ml=3.4  EMSC   CENTRAL CALIFORNIA

P:  4JAN2021 129987    36.6N  120.7W 2.5-4.7 AAAAA  Central California         

P:  4JAN2021 129988    36.9N  121.7W 2.5-5.1 AAAAA  Central California         

P:  7JAN2021 129988    36.7N  121.4W 2.5-5.0 BAAAA  Central California         

 

An earthquake of M 4.2 also occurred in southern Idaho on the border with Wyoming today. NEIC reported it was felt with maximum intensity IV in Idaho at Bern, Montpelier and II-III in Grace, Soda Springs, Thatcher, Paris, Preston, Afton and Auburn and at Smoot, Wyoming. This is not an aftershock of the series in southwestern Idaho following the M 6.5 there on March 31, 2020 but follows after several moderate aftershocks in that series in recent days. The last earthquake in southern Idaho within about 150 km of today's epicenter with M>=4.2 occurred on January 26, 2018 with M 4.3 - part of an aftershock series following an M 5.3 on September 2, 2017. That was the last such event in that series (until today). Today's event had been expected within about 75 km to occur around January 7 (forecast 130097).

 

O:  3JAN2021 05:35:28  42.6N  111.5W Ml=4.2  EMSC   SOUTHERN IDAHO                

P:  7JAN2021 130097    43.2N  111.0W 2.0-3.9 BAAAA  Yellowstone/Wyoming        

 

USUAL QUAKE SHAKES BELGIUM

 

EARTHQUAKE SUMMARY FOR JANUARY  1, 2021

 

An unusual earthquake of M 2.5 occurred in northwestern Germany near the Belgium border today. NEIC reported it was felt with intensity III in Raren, Belgium and in Nordrhein, West Falen, Germany at Aachen and Stolberg. The last earthquake located in Belgium with equal or greater magnitude was an M 3.0 on October 31, 2019. Earthquakes with M>=2.5 within about 100 km of today's epicenter have most recently occurred as an M 2.9 on May 25, 2018 and an M 2.9 on January 20, 2013.

The largest earthquake in the area in the past 30 years was an M 5.4 on April 13, 1992 - part of an induced swarm due to water injection. This was abandoned when it was realized it was causing earthquakes and the activity in the area ceased. Only seven earthquakes of M>=2.5 have been recorded in the area since 2008. Forecast 130112 had expected today's event was likely around January 4 within about 50 km of this epicenter.

 

O:  2JAN2021 06:36:28  50.6N    6.2E ML=2.5  EMSC   BELGIUM                      

P:  4JAN2021 130112    51.0N    6.0E 3.0-4.8 AAAAA  Netherlands/Belgium        

 

An M 5.1 also occurred in the Caucasus region of Russia. NEIC reported intensity VIII with damage in Gedzhukh, and IV in Dagestan, Russia. The last earthquake within about 200 km of this epicenter with M>=5.1 was an M 5.1 on February, 2019. The last of larger magnitude was an M 5.3 on June 5, 2018. Forecast 130054 had expected today's activity in the Caucasus around January 4.

 

O:  2JAN2021 01:05:51  42.1N   48.0E mb=4.7  EMSC   CASPIAN SEA                  

O:  2JAN2021 01:05:51  42.1N   48.0E mb=5.1  ANSS   CASPIAN SEA                  

P:  4JAN2021 130054    43.0N   44.0E 3.5-5.1 AACAA  Caucasus/Caspian Sea       

 

An unusually large earthquake of M 4.7 shook the Madeira Islands of Portugal today. The last earthquake of M>=4.7 in the Madeira Islands area within about 250 km of today's event was an M 5.2 on March 7, 2020, the only such event in the area in the past 30 years. Forecast 129667 had expected regional activity around January 1 in the Canary Islands about 400 km to the south  of today's epicenter. That region also continued active and may in preparatory stages for an eruption of Tenirefe Volcano. Earthquakes of M>=4.7 in the Canary Islands in the past 30 years included an M 5.4 on December 28, 2013 and M 4.7's on March 29, 2013, November 8, 2008 and March 21, 1991.

 

O:  1JAN2021 21:06:44  32.3N   16.7W mb=4.7  EMSC   MADEIRA ISLANDS, PORTUGAL REGI

P:  1JAN2021 129667    28.0N   16.0W 3.0-4.3 ACAAA  Canary Islands             

 

O:  2JAN2021 04:49:19  28.1N   16.2W ML=1.9  EMSC   CANARY ISLANDS, SPAIN REGION 

P:  1JAN2021 129667    28.0N   16.0W 3.0-4.3 AAAAA  Canary Islands             

 

A series of earthquakes also occurred in the region of Guatemala. This included an M 5.0 and several moderate shocks associated with it. NEIC reported this earthquake of M 5.0 in offshore Guatemala was felt with intensity II-III in the area(s) of  Guatemala at Villa Canales and Mixco.  NEIC reported this earthquake of M 4.3 in Sacatepequez was felt with intensity III-IV in the area(s) of  Sacatepequez, Guatemala at Ciudad Vieja and San Pedro. This activity is located at 103 degrees from the Dodecanese Islands quake of M 7.0 on October 30, 2020 and was probably promoted from that source. Other earthquakes at this distance from Greece today occurred in Central California, the Gulf of California, Baja California, Banda and Ceram, Indonesia, Costa Rica. Forecasts 129641 and 129933 had expected this activity in late December or in early January.

 

O: 01JAN2021 22:49:00  13.5N   90.8W mb=4.4  EMSC   OFFSHORE GUATEMALA

O: 02JAN2021 00:42:18  13.8N   91.2W mb=4.3  EMSC   OFFSHORE GUATEMALA

O:  1JAN2021 22:11:26  12.8N   91.2W Mw=5.0  EMSC   OFF THE COAST OF GUATEMALA   

P: 29DEC2020 129641    14.0N   92.0W 3.5-5.0 BBAAA  Guatemala                  

P:  8JAN2021 129933    13.0N   91.0W 3.5-5.4 CAAAA  Guatemala                  

 

This summary is adding additional data for earth-affecting events such as GRBs and X-Ray events, sunspot numbers and Radio frequency information. Many of these may be tied to the timing and magnitude of subsequent seismicity on the earth. This is located under the "GEOMAGNETIC" section of this summary.

 

ATLANTIC RIDGE SEES MODERATE ACTIVITY

 

EARTHQUAKE SUMMARY FOR DECEMBER 31, 2020

 

The strongest earthquakes in the world today were of M 5.1-5.2. One of these was an M 5.2 in the Southern Mid-Atlantic near the antipode of the Rat Islands, Alaska. It occurred several hours after an M 4.3 at the Rat Islands antipode but was probably not related to that event, the strongest in the Rat Islands since N 4.9 on September 24. Today's event occurred within about 15 minutes of local solar midnight in the South Atlantic and was likely promoted by strong tidal effects related to the full moon of December 30. Forecast 129875 had expected today's event around December 31.

 

O:  1JAN2021 00:40:35  52.2S    4.8W mb=5.2  EMSC   SOUTHERN MID-ATLANTIC RIDGE  

P: 31DEC2020 129875    55.0S    2.0E 4.0-5.3 ACCAA  Atlantic-Indian Ridge      

 

An unusual earthquake of M 5.1 also occurred in the Southern Azores of the North Atlantic today. The only such earthquakes within about 200 km of this epicenter in the past 20 years occurred on April 30, 2013 (M 5.8) and in early April, 2007 when a strong series including an M 6.3 hit the region. Today's event had not been anticipated in this summary.

 

O: 31DEC2020 22:55:56  36.9N   24.3W mb=5.1  EMSC   AZORES ISLANDS REGION        

 

Earthquakes of M 5.1-5.2 were also recorded in Indonesia today in the Admiralty Islands and in the Flores region. Neither was widely felt. Forecasts 129906 and 129615 had expected this activity at the end of December or in early January, 2021.

 

O: 31DEC2020 19:50:17   0.8S  146.8E Mw=5.2  EMSC   ADMIRALTY ISLANDS REGION, P.N.

P:  2JAN2021 129906     3.0S  146.0E 4.0-5.3 ACAAA  New Ireland                

 

NEIC reported the earthquake of M 5.1 in Flores Indonesia was felt with intensity II-III in the area(s) of Flores Indonesia at Maumere.

 

O: 31DEC2020 10:18:54   8.8S  122.3E Mw=5.1  EMSC   FLORES REGION, INDONESIA     

P: 26DEC2020 129615     8.0S  122.0E 4.0-5.6 BAAAA  Flores Island area         

P:  1JAN2021 129615     7.0S  121.0E 4.0-5.4 ABAAA  Flores Island area         

 

An M 4.0 earthquake shook areas of western Texas today and was preceded by light foreshocks and followed by several felt aftershocks. The mainshock was reported by NEIC to have been felt with maximum intensity VI in Texas at Lenorah and Midland with IV in Stanton and II-II in Knott, Tarzan, Big Song. NEIC reported aftershocks of M 2.6 and M 3.1 in Western Texas were felt with intensity II-III in the area(s) of Western Texas at Lenorah. The M 4.0 was preceded by a series starting with an M 3.3 at 18:21 UT. This is within about 15 minutes of local solar noon, a time when tidal stresses with the full moon of December 30 would have been maximized. It is likely this series was enhanced by these tidal stresses. Forecast 130024 had expected today's activity was likely within about 50 km of this epicenter in early January, 2021. The M 4.0 is the strongest within about 100 km of this epicenter in at least 30 years. A similar event of M 4.0 hit about 150 km to the northeast on September 20, 2019 and an M 4.3 occurred near that epicenter on September 11, 2011.

 

O: 31DEC2020 18:21:33  32.3N  101.8W mb=3.3  EMSC   WESTERN TEXAS

O: 31DEC2020 19:12:33  32.3N  101.8W mb=3.6  EMSC   WESTERN TEXAS

O: 31DEC2020 20:44:20  32.3N  101.8W Mw=4.0  EMSC   WESTERN TEXAS

O: 31DEC2020 20:56:56  32.3N  101.8W mb=2.5  EMSC   WESTERN TEXAS

O:  1JAN2021 04:49:35  32.3N  101.8W mb=2.6  EMSC   WESTERN TEXAS                

O:  1JAN2021 01:23:24  32.3N  101.8W mb=3.1  EMSC   WESTERN TEXAS                

P:  2JAN2021 130024    32.5N  101.6W 2.0-4.2 AAAAA  SW U.S.A                   

 

An M 4.0 and aftershocks also occurred in the southern Idaho aftershock zone today. NEIC reported this earthquake of M 3.9-4.0 in Southern Idaho was felt with intensity II-III in the area(s) of Southern Idaho at Ketchum, Twin Falls. It is located east of the normal aftershock zone of the M 6.5 of March 31, 2020 and may indicate a new seismic source. This is the strongest aftershock in southern Idaho since an M 4.7 on November 13, 2020. The only other such event in the past five months was an M 4.4 on November 6. Today's activity may have been promoted by strong X-ray solar flux event  minutes before the M 4.4 at 04:40 UT. Forecast 129760 had expected enhanced  seismicity in this aftershock zone in late December.

 

O: 01JAN2021 03:17:22  44.1N  114.9W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 01JAN2021 05:26:08  44.1N  114.9W Ml=4.0  EMSC   SOUTHERN IDAHO

O: 31DEC2020 11:32:14  44.3N  115.2W Ml=3.5  EMSC   SOUTHERN IDAHO

O: 31DEC2020 13:39:39  44.3N  114.8W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 31DEC2020 14:36:34  44.3N  115.0W Ml=2.5  EMSC   SOUTHERN IDAHO

O: 31DEC2020 14:36:34  44.3N  115.0W Ml=2.5  EMSC   SOUTHERN IDAHO

O: 31DEC2020 10:32:49  44.5N  115.2W Ml=2.1  EMSC   SOUTHERN IDAHO

O: 31DEC2020 23:38:15  44.5N  115.2W Ml=2.4  EMSC   SOUTHERN IDAHO

O: 31DEC2020 16:22:47  44.0N  115.0W ML=3.4  EMSC   SOUTHERN IDAHO               

P: 28DEC2020 129760    44.4N  115.2W 2.0-3.9 BAAAA  Montana/Idaho              

 

Another earthquake of M 4.0 in Canada today occurred west of British Columbia. The only event of M>=4.0 within about 100 km of this epicenter in this past year was an M 4.1 on September 22, 2020. Forecast 129784 had expected today's activity was likely at the end of December.

 

O: 31DEC2020 11:10:39  47.5N  129.0W MB=4.0  ECAN Tofino, BC                     

P: 29DEC2020 129784    49.5N  127.2W 2.8-4.8 ABBAA  Vancouver Island area      

 

Aftershocks in Croatia continued to be felt today. The largest of these was an M 3.7 which NEIC reported with intensity V in Croatia at Gvozd and II-III in Zagrec, and in Bosnia and Herzegovina and Slovenia. Forecast 130051 had expected today's activity around January 2. No further major damage or casualties were reported with today's activity in the region of Zagreb.

 

O: 01JAN2021 05:37:21  45.5N   16.2E ML=3.8  EMSC   CROATIA

O: 31DEC2020 10:42:02  45.5N   16.0E ML=3.4  EMSC   CROATIA

O:  1JAN2021 03:52:54  45.4N   16.2E ML=3.6  EMSC   CROATIA                      

P:  2JAN2021 130051    45.0N   16.0E 3.0-5.2 AAAAA  Adriatic Sea               

 

A series of moderate and light earthquakes also occurred today in the Mt. Etna area of Sicily. This is probably related to enhanced volcanism with the full moon. The current eruption began with the new moon on December 14 which also saw enhanced seismicity on December 22, 2020 and an M 4.6 south of Etna. Forecast 130005 had expected this activity was likely around January 1, 2021.

 

O: 31DEC2020 20:58:09  37.6N   15.0E ML=3.9  EMSC   SICILY, ITALY

O: 31DEC2020 21:54:39  37.6N   15.0E ML=4.2  EMSC   SICILY, ITALY

O: 31DEC2020 20:30:53  37.6N   15.0E ML=4.0  EMSC   SICILY, ITALY                

P:  1JAN2021 130005    38.0N   14.0E 3.0-4.4 AAAAA  Mediterranean/Sicily       

 

An unusual set of earthquakes occurred offshore Los Lagos, Chile today, the area of the M 6.7 on December 27. These are about 300 km southeast of that epicenter, however and may have been triggered by regional stress redistribution following the December event. Forecast 1301818 expects further activity in the area in the coming week.

 

O: 31DEC2020 10:48:45  41.7S   74.2W ML=3.4  EMSC   OFFSHORE LOS LAGOS, CHILE    

P:  7JAN2021 130181    40.0S   75.0W 4.0-5.6 CBAAA  Central Chile              

 

MAJOR SEISMICITY REVIEW FOR THE YEAR 2020

 

EARTHQUAKE SUMMARY FOR DECEMBER 30, 2020

 

The year 2020 was a fairly typical year in global seismicity but became quiet towards the end of the year. The largest earthquake in the world this year was an M 7.7 in the Cayman Islands west of Cuba on January 28. A pair of earthquakes of M 7.6 and 7.8 occurred on July 22 and October 19, 2020 in the Alaska Peninsula region. None of these three events caused damage and tsunamis were not particularly notable this year. Strong earthquakes occurred with solar eclipses in Chile in December and in India and Myanmar in June. Following is a listing of earthquakes in the world this year with Magnitude greater than or equal to M 7.0. Quakes in Chile of M>=6 were simultaneous with the December 14, 2020 solar eclipse and an M 6.7 hit at the point of eclipse maximum in Los Lagos, Chile later in December. At least half of the largest earthquakes of M>=7 this year occurred within a day of a major GRB including one of the most deadly quakes in the world - an M 6.4 in Croatia aon December 29. These included quakes in the Cayman Islands, Oaxaca, Mexico, the Alaska Peninsula and Greece. Seismicity was strong near 103 degrees from the largest quakes as well as at the fourth node (90 degrees).

 

MO DA HR MN SC YEAR   LAT     LONG    DEPTH MAG LOCATION

 

 1 28 19 10 25 2020   19.440  -78.754  10.0 7.7 Cayman Islands

 2 13 10 33 44 2020   45.631  148.929 144.0 7.0 Kuril Islands

 3 25  2 49 21 2020   48.986  157.693  56.7 7.5 Kuril Islands

 6 18 12 49 53 2020  -33.294 -177.838  10.0 7.4 Kermadec Islands

 6 23 15 29  4 2020   15.932  -95.937  20.0 7.4 Oaxaca, Mexico

 7 17  2 50 23 2020   -7.843  147.766  79.8 7.0 New Guinea

 7 22  6 12 44 2020   55.030 -158.522  28.0 7.8 Alaska Peninsula

10 19 20 54 39 2020   54.608 -159.655  33.3 7.6 Alaska Peninsula

10 30 11 51 27 2020   37.918   26.790  21.0 7.0 Dodecanese Is, Greece

 

On the other hand, seismicity in the U.S., Canada and Possession this year was at high levels. The strongest events were those of M 7.6 and 7.8 in the Alaska Peninsula noted above. But a series of large earthquake also occurred this year in this area which were moderately damaging and in some cases caused casualties.

The first of these was an M 6.4 in the Ponce area of Puerto Rico on January 7, 2020. This earthquake did much damage in southern Puerto Rico and killed at least one person. A pair of earthquakes of M 5.6 and 6.5 followed in the region of Salt Lake City and southern Idaho on March 18 and 31 respectively. These events also caused minor regional damage but no deaths. The Idaho aftershock sequence continues to this date. An M 6.5 in Central California on May 15, 2020 was followed by a series of moderate events including those of M 5.6-5.8 in California on June 4 and 24, 2020. These were widely felt but did little regional damage. A pair of moderate to strong quakes on December 1, 2020 occurred within 14 minutes and were associated with a strong increase in radio activity on the sun. An eruption at Kilauea, Hawaii broke a two year long quiet in that region. It started with the solar eclipse of December 14 and broke loose on December 21. Following is a listing of significant earthquake in the U.s, Canada and Possessions this year.

  

MO DA HR MN SC YEAR   LAT     LONG    DEPTH MAG LOCATION

 

 1  7  8 24 26 2020   17.916  -66.813  10.0 6.4 Southern Puerto Rico

 1 23  5 53  3 2020   51.920 -177.827  10.0 6.2 Andreanof Islands, Alaska

 1 26  6 31 57 2020   51.346 -179.917  27.1 6.1 Andreanof Islands, Alaska

 3 18 13 98 31 2020   40.700 -112.100  10.0 5.7 Utah

 3 31 23 52 31 2020   44.448 -115.136  10.0 6.5 Southern Idaho

 5 15 11  3 27 2020   38.159 -117.875   2.8 6.5 Nevada/California

 6  4  1 32 11 2020   35.615 -117.428   8.4 5.5 Central California

 6 24 17 40 49 2020   36.447 -117.975   4.7 5.8 Central California

 7 22  6 12 44 2020   55.030 -158.522  28.0 7.8 Alaska Peninsula

 7 22  6 16 18 2020   54.932 -159.042  17.7 6.1 Alaska Peninsula

 7 28  8  3 44 2020   54.867 -161.144  41.3 6.1 Unimak, Alaska

10 19 20 54 39 2020   54.608 -159.655  33.3 7.6 Alaska Peninsula

12  1 16 22 39 2020   52.781 -168.300  23.0 6.4 Fox Islands

12  1 16 35 48 2020   53.708 -150.596  10.0 5.7 Southern Alaska

12 29  7 10 29 2020   43.371 -126.914  10.0 5.7 Off Coast of Oregon

 

Light aftershocks continued today in the region of Croatia and were felt with light to moderate intensity. But there were no events of M>4 in the area today and further damage was mitigated. Forecasts 129746 and 129755 had expected regional enhanced seismicity in the area at the end of December.

 

O: 30DEC2020 08:21:23  45.4N   16.2E ML=4.0  EMSC   CROATIA                      

P: 24DEC2020 129746    44.0N   18.0E 3.0-4.8 CBBAA  Adriatic Sea               

P: 24DEC2020 129755    43.0N   16.0E 3.0-5.1 CCAAA  Italy                       

 

An M 3.8 today in Kansas was widely felt in the area of Wichita with intensity IV-V. This is the strongest earthquake in Kansas since an M 4.5 on January 19, 2020. No other such earthquake has occurred in Kansas in the past year. Today's event was probably enhanced by strong tidal stresses associated with the full moon which occurred several hours earlier. This summary had noted the possible  seismic effects of the full moon in earlier summaries as:

 

"The full moon arrived at 03:28 UT on December 30, 2020. Longitudes which were anti-solar (local solar midnight) at this time are near 55  West and those sub-solar at 125 East longitude. These include in the west areas of western South America and northern Caribbean including the area of the Virgin Islands and Puerto Rico and in the east areas of central Indonesia, the Philippines, Taiwan and north to Japan. These area are most likely to see increased tidal triggering in the next week. Tidal triggering is most likely at local solar noon and midnight, but can occur in other areas and times. A strong earthquake is possible due to tidal triggering in the next week." (December 27-30, 2020)

 

The area of Oklahoma and Kansas often seen enhanced seismicity with full and new moons. Forecast 129736  had expected today's activity was likely around December 28.

 

O: 31DEC2020 04:52:43  37.7N   97.2W mb=2.4  EMSC   KANSAS                       

O: 30DEC2020 11:04:44  37.7N   97.2W mb=3.8  EMSC   KANSAS                       

P: 28DEC2020 129736    37.0N   97.0W 2.0-3.8 AAAAA  Southern Plains            

 

The strongest earthquake in the U.S. or Canada today was an M 4.3 in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote area. Recent earthquake of M>=4.3 in the Rat Islands occurred as an M 4.5 on September 24, 2020 and an M 4.6 on August 27, 2020. Forecast 129806 had expected this activity in the Rat Islands was likely at the end of December.

 

O: 31DEC2020 04:10:09  51.6N  178.5E mb=4.3  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 28DEC2020 129806    52.0N  175.0E 4.0-5.5 BABAA  Rat Islands                

 

M 6.4 IN CROATIA MAY HAVE BEEN TRIGGERED BY STRONG GAMMA RA?Y BURST

 

EARTHQUAKE SUMMARY FOR DECEMBER 29, 2020

 

A strong earthquake of M 6.4 struck the area of Croatia today. NEIC reported it

was felt with maximum intensity IV in Croatia at Petrinja, and Bosanska Bosnia and Herzegovina; VIII in Sisak, Croatia; VI in Potik, Gvoza, VI in Kriz, Gradici, and VI-V in Croatia at Glina, Busevec and Mraolin among others. 

It was also felt in Czechia, Germany, Hungary, Italy, Montenegro, Romania, Slovakia, Slovenia, Serbia and Austria. Initial reports indicate at least seven  persons were killed in the earthquake with considerable damage seen in web images from the region especially in Central Croatia at Petrinja and Zagreb. Five of the deaths occurred in Glina and another in the rubble of a church in Zazina. About half of Petrinja was destroyed according to the mayor of of that town. There was general panic in this town of about 20,000. As aftershocks caused more damage many residents spent the night in military barracks or in their cars. Injuries also occurred is Sisak where hsopitals were over-crowded.

 

A major Gamma Ray Burst (GRB) was observed on December 29, 2020 at 11:00 UT.

This was followed 20 minutes later by the M 6.4 in Croatia. It is possible that energy associated with this GRB helped trigger the M 6.4 in Croatia at this time.

 

An updated catalog of Gamma Ray Bursts (GRB) is again available. A summary examination of these shows that many of the largest is associated with strong or major earthquakes in recent years. This summary followed this when the previous catalog was available and it will therefore again add GRB data to this summary and note it when a major GRB coincides closely with a strong earthquake. This can be found in the "GEOMAGNETIC" section of this report.

 

Today's activity followed earthquakes of M 5.2 and 5.0 two days ago in the same area as noted in the previous summary:

 

"A pair of earthquakes of M 5.2 each also occurred in Croatia today. NEIC reported they were felt with damage in Croatia at Moscenica and Sisak (VII) and Petrinja and Glina (VI); V shaking was observed in Lekenik, Gradici; IV in Potok, Odra with lesser intensity in Kriz, Zagreb and Bosnia and Herzegovina. These epicenters are at 118 degrees (near node 3) from the quake in Los Lagos and may have been promoted by energy from that source. The only earthquake in the region of Croatia within about 200 km of today's activity in the past 30 years occurred about 50  km northwest of today's epicenter with M 5.4 on March 22,  2020. Forecasts 129746 and 129755 had expected today's activity was likely around December 24." (December 28, 2020)

 

and

 

"Elevated seismicity continued in the region of Croatia today following the M 5.2 and 5.0 there yesterday. An M 4.7 was felt with intensity VI in Petrinja; V in Sisak, Voloder, Ilova; IV in Zagreb, Bjelovar and II-III in Vrbovec, Potok, Lutina, Seavete, Croatia. This activity is likely to continue with the possibility of a strong, damaging quake in the next several days. Today's activity included activity at two different epicenters in Croatia - as aftershocks near Zagreb and with an M 3.2 near Otok, Vis about 250 km to the south." (December 28-29, 2020)

 

The last earthquake within about 150 km of today's earthquake with M>=6.4 was an M 6.5 on January 28, 1900. Two other events in this area have been recorded in modern history - an M 7.0 on December 26, 1813 and na M 6.9 on March 26, 1511.  

Forecasts 129746 and 129755 had expected today's activity was likely around December 24. A series of events of M 6.5 occurred in northern Italy about 200 km west of this occurred in May and September, 1976 and about 200 km to the southeast on October 26 and 27, 1969.  The earthquake of M 6.4 occurred within about 30 minutes of local solar noon and was probably promoted by high tidal stresses associated with today’s full moon.

 

O: 30DEC2020 05:26:40  45.4N   16.2E mb=4.7  EMSC   CROATIA

O: 29DEC2020 11:19:54  45.5N   16.3E Mw=6.4  EMSC   CROATIA

O: 29DEC2020 17:29:06  45.5N   16.2E ML=3.9  EMSC   CROATIA

O: 29DEC2020 17:57:33  45.5N   16.3E ML=3.9  EMSC   CROATIA

O: 30DEC2020 05:15:04  45.5N   16.2E ML=4.8  EMSC   CROATIA

O: 29DEC2020 12:34:42  45.4N   16.2E mb=4.4  EMSC   CROATIA                      

P: 24DEC2020 129746    44.0N   18.0E 3.0-4.8 BBBAA  Adriatic Sea               

P: 24DEC2020 129755    43.0N   16.0E 3.0-5.1 BCAAA  Italy                      

 

The event in Croatia may have triggered a regional aftershock in northern Italy  today. This event of M 4.4-4.6 occurred about 300 km west of the Croatian epicenter. NEIC reported this earthquake of M 4.6 in northern Italy was felt with intensity II-III in the area(s) of northern Italy in Veneto at Salizzole, Bovolone, Melara, Verona, Soave, Lazise and Cavaion Veronese and IV in Zebio and San Giovani Lupatoto and in San Benedetto Po Lombardei. The last such event within about 150 km of today's event in northern Italy was an M  4.8 about 150 km southeast of today's epicenter on December 9, 2019 and prior to that an M 5.2 on June 3, 2012 - an aftershock of an M 5.8 on May 29, 2012 and an M 6.0 on May 20, 2012. This summary noted that event at the time as:

 

"AFP news reported the mainshock of M 6.1-6.3 killed at least three people and

injured at least 50. the M 4.1 foreshock shook the area of Lombardy around

Milan and was felt in the historic cities of Modena, Mantua, Ferrara and

Rovigno. The three fatalities were night shift workers. The earthquake occurred near the time of maximum tidal effect. Most of the injured were located in Modena. Thousands rushed into the streets in Bologna and Telephone and emergency services were out. Television showed collapsed houses and heaps of rubble on the road and church steeples and towers were nearly collapsed. Hospitals were evacuated as a precaution. A number of people are believed buried in the rubble and deaths and injuries are likely to rise. The area is Italy's industrial heartland and home to architectural and art treasures and the center of Ferrara is a world heritage site, so damage to the region is not easily taken or repaired." (May 20, 2012)

 

Forecast 129747 had expected this activity in this region was likely around

December 27.

 

O: 29DEC2020 14:36:56  45.2N   11.0E ML=4.4  EMSC   NORTHERN ITALY               

O: 29DEC2020 14:36:56  45.2N   11.1E ML=4.6  ANSS   NORTHERN ITALY               

P: 27DEC2020 129747    45.0N   10.0E 3.0-4.9 AAAAA  Austria                    

 

An M 5.9 also occurred today in the Central Mid-Atlantic Ocean. This is the strongest earthquake within about 200 km of this epicenter since an M 6.4 on December 9, 2009. It may have been promoted by tidal stresses associated with the full moon as it occurred near local solar midnight. Forecast 129612 had expected this activity was likely around December 31.

 

O: 29DEC2020 23:34:58   0.8S   21.1W Mw=5.9  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P: 31DEC2020 129612     1.0S   20.0W 4.0-5.3 AAAAA  Central Mid-Atlantic       

 

The strongest earthquake in the U.S. or Canada today was an M 5.7 off the Coast of Oregon. NEIC reported it was felt lightly along the coast in Bandon, Langlois, Port Orford, Coquille, Coos Bay, Gold Beach, Lakeside, North Bend, Florence, and Newport, Oregon. This event occurred near local solar midnight and may have been promoted by tidal triggering associated with the full moon on December 30 as noted in this and previous issues of this summary:

 

"The full moon will arrive at 03:28 UT on December 30, 2020. Longitudes which are anti-solar (local solar midnight) at this time are near 55  West and those sub-solar at 125 East longitude. These include in the west areas of western South America and northern Caribbean including the area of the Virgin Islands and Puerto Rico and in the east areas of central Indonesia, the Philippines, Taiwan and north to Japan. These area are most likely to see increased tidal triggering in the next week. Tidal triggering is most likely at local solar noon and midnight, but can occur in other areas and times. A strong earthquake is possible due to tidal triggering in the next week." (December 26-29, 2020)

 

The last earthquake of M>=5.7 within about 200 km of this epicenter occurred with M 5.9 on September 5, 2019, an aftershock of an M 6.3 on August 29, 2019.

Forecast 129773 had expected today's activity around December 27. Today epicenter is near the fourth node (90 degrees) from the Los Lagos M 6.8 and may have been promoted by energy from that source.

 

O: 29DEC2020 10:14:55  43.1N  126.7W ML=3.2  EMSC   OFF COAST OF OREGON

O: 29DEC2020 07:10:31  43.4N  127.0W Mw=5.7  EMSC   OFF COAST OF OREGON          

P: 27DEC2020 129773    42.5N  126.8W 3.0-4.6 AAAAA  Off Coast of Oregon        

 

ELEVATED SEISMICITY CONTINUES IN CROATIA

 

EARTHQUAKE SUMMARY FOR DECEMBER 28, 2020

 

Elevated seismicity continued in the region of Croatia today following the M 5.2 and 5.0 there yesterday. An M 4.7 was felt with intensity VI in Petrinja; V in Sisak, Voloder, Ilova; IV in Zagreb, Bjelovar and II-III in Vrbovec, Potok, Lutina, Seavete, Croatia. This activity is likely to continue with the possibility of a strong, damaging quake in the next several days. Today's activity included activity at two different epicenters in Croatia - as aftershocks near Zagreb and with an M 3.2 near Otok, Vis about 250 km to the south. This activity was expected around December 24 in forecasts 129746 and 129755.

 

O: 29DEC2020 00:19:01  45.4N   16.2E ML=2.8  EMSC   CROATIA                       

P: 24DEC2020 129746    44.0N   18.0E 3.0-4.8 BBAAA  Adriatic Sea               

 

O: 29DEC2020 04:18:12  43.0N   16.2E ML=3.2  EMSC   OTOK VIS, CROATIA            

P: 24DEC2020 129755    43.0N   16.0E 3.0-5.1 BAAAA  Italy                       

 

The strongest earthquake in the region of California today occurred as an M 4.4 in the region of the Gulf of California. NEIC reported it was felt with intensity II in San Luis Rio Colorado, Sonora, Mexico and possibly in Phoenix, Arizona. It was preceded by an M 3.6 regional event also felt in Sonora and Arizona. It was accompanied by a series of events including an M 3.6, 3.3 and 3.2 in Baja California which stared about six hours earlier with the M 3.6. This series was expected in forecast 129723 around December 27 within about 50 km of these epicenters. This activity is at 103 degrees from the Dodecanese Islands M 7.0 of October 30, 2020 and may have been promoted by energy from that source. Other events at 103 degrees from the Dodecanese event occurred as a series in Guatemala and in the Banda Sea and an M 5.5 in Molucca, Indonesia.

 

O: 28DEC2020 15:29:08  31.4N  114.8W mw=4.4  ANSS   San Felipe Mexico            

P: 31DEC2020 129717    30.2N  114.1W 2.0-3.8 BBAAA  SW U.S.A                   

 

O: 28DEC2020 10:36:32  31.5N  115.6W ML=3.5  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 14:36:30  32.3N  115.1W Ml=3.3  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 14:41:34  32.3N  115.1W Ml=2.5  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 15:29:24  32.3N  115.1W Ml=2.6  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 15:41:40  32.3N  115.1W Ml=2.5  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 14:34:52  32.4N  115.2W ML=3.2  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 15:04:15  32.4N  115.2W Ml=2.3  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 14:29:09  32.5N  115.2W Ml=2.3  EMSC   BAJA CALIFORNIA, MEXICO

O: 28DEC2020 09:45:32  31.4N  115.5W ML=3.6  EMSC   BAJA CALIFORNIA, MEXICO      

P: 27DEC2020 129723    32.5N  115.7W 2.5-4.3 ABAAA  So. California              

P: 31DEC2020 129717    30.2N  114.1W 2.0-3.8 BBBAA  SW U.S.A                   

 

The strongest earthquake in the U.S. or Canada today was an M 4.3 in the Near Islands, Aleutians, Alaska. NEIC reported this earthquake of M 4.3 in the Near Islands, Alaska was felt with intensity II-III in the area(s) of the Near Islands, Alaska at Attu. This may be a regional aftershock of an M 5.3 on December 9, 2020 which occurred about 200 km to the northwest of today's epicenter. Forecast 129801 had expected today's event around December 27.

 

O: 29DEC2020 00:47:23  52.3N  172.3E mb=4.3  EMSC   NEAR ISLANDS, ALEUTIAN ISLANDS

P: 27DEC2020 129801    53.0N  170.0E 4.0-5.6 AABAA  Near Islands               

 

Two light earthquakes were felt today in southern Quebec, Canada. The larger of these was an M 3.4 in the St. Lawrence Valley where it was lightly felt. It was followed by aftershocks of M 2.3 and 1.1. The other was an M 2.8 in Southern Quebec near Ferme-Neuve where it was lightly felt. The M 3.4 in the St. Lawrence Valley is the strongest within about 200 km of this epicenter since an M 3.7 on January 21, 2015. The last of M>=4 in the area was an M 4.4 on July 11, 2013.   Forecast 129758 had expected today's event within about 50 km of this epicenter was likely around December 28. This event is at the seventh node (52 degrees) from the M 7.6 in the Gulf of Alaska of October 19 and may have been promoted from that source.

 

O: 28DEC2020 18:13:02  47.6N   70.2W MB=1.1  ECAN La Malbaie, QC. Aftershock  

O: 28DEC2020 14:36:57  47.6N   70.2W MB=2.3  ECAN La Malbaie, QC. Aftershock  

O: 28DEC2020 14:19:50  47.6N   70.2W MB=3.4  ECAN La Malbaie, QC, felt  

O: 28DEC2020 14:19:50  47.6N   70.2W ML=3.4  EMSC   ST. LAWRENCE VALLEY REG., CANA

P: 28DEC2020 129758    47.0N   70.0W 2.0-4.0 AAAAA  Maine                      

 

The earthquake of M 2.8 near Ferme-Neuve, Quebec was near the antipode of an M 5.1 and 5.2 in the Southeast Indian Ridge which occurred about 6 hours earlier. It is possible it was promoted by energy from that source. Forecast 129768 had expected today's event within about 50 km was likely around December 24.

 

O: 28DEC2020 10:56:36  47.1N   76.4W MB=2.8  ECAN Ferme-Neuve, QC    

O: 28DEC2020 10:56:36  47.1N   76.4W ML=2.8  EMSC   SOUTHERN QUEBEC, CANADA      

P: 24DEC2020 129768    47.0N   76.0W 2.0-3.8 BAAAA  New York State             

 

The eruption of Kilauea Volcano in Hawaii entered its second week today. The strong eruption of lava filled a fissure while the lava lake continues to  overflow. Forecast 129643 had expected this activity was likely around December 30.

 

O: 28DEC2020 23:26:50  19.2N  155.5W ML=3.3  EMSC   ISLAND OF HAWAII, HAWAII     

P: 30DEC2020 129643    18.8N  155.2W 3.0-4.3 AAAAA  Hawaii                     

 

An M 4.9 near Barbuda, Leeward Islands today was lightly felt in that region. This is the strongest earthquake near Barbuda since an M 5.2 about 150 km west of this occurred on February 9, 2018. Forecast 129644 had expected today's event in the Leeward Islands was likely around December 27.

 

O: 28DEC2020 08:25:34  18.8N   60.5W mb=4.9  EMSC   NE OF BARBUDA, LEEWARD ISLANDS

P: 27DEC2020 129644    16.0N   60.0W 3.0-4.9 ACAAA  Leeward Islands            

 

Aftershocks of the M 6.7 in the Los Lagos area of Chile continued today with

events, among others, of M 4.4, 4.6 and 4.7. Readers are referred to previous issues of this summary (December 26, 27, 28, 2020). This activity had been expected in late December north of these epicenters.  It may be of interest, and previously unreported here, that the M 6.7 occurred  simultaneously with landfall of Tropical Chalane on Madagascar. These two locations are at 103 degrees apart and energy from the landfall may have helped promoted the activity in Chile at this time.

 

"TC    CHALANE  2020-12-27  00:00 UT  18.1S   47.6E   35 kts  East of Madagascar          

TC Chalane (07S) continued today in the South Indian Ocean east of Madagascar with winds up to 35 kts. It is expected to track to the west over the next several days and my impact regional seismicity in the next several days." (December 27-28, 2020)

 

O: 28DEC2020 08:51:15  39.4S   75.1W mb=4.6  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 28DEC2020 15:58:33  39.4S   74.9W mb=4.7  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 29DEC2020 06:44:40  39.7S   75.1W ML=3.9  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 28DEC2020 13:03:13  39.2S   74.8W mb=4.4  EMSC   OFF COAST OF LOS LAGOS, CHILE

P: 24DEC2020 129861    37.0S   73.0W 4.0-5.3 BCBAA  Central Chile              

 

M 6.7-6.8 IN LOS LAGOS, CHILE TIED TO TOTAL ECLIPSE OF THE SUN

 

EARTHQUAKE SUMMARY FOR DECEMBER 27, 2020

 

An earthquake of M 6.7-6.8 shook south-Central Chile in the region of Los Lagos today. This is the strongest earthquake in the world in nearly two months - since an M 7.0 in the Dodecanese Islands, Greece on October 30, 2020. It occurred  at an epicenter where the total eclipse of the sun was maximized on December 14 and is a prime example of high tidal stresses associated with eclipses affecting subsequent seismicity. A series of strong quakes has occurred in Chile since December 14, including one within minutes of the eclipse in northern Chile, but the location of today's event at precisely the point of maximum eclipse in Chile is strong evidence for tidal triggering.

 

NEIC reported today's event was felt with maximum intensity V in Los Lagos, Chile in Valdivia; IV in La Union, Rio Bueno, Osorno, and II-III in Purranque, Panguipulli, and in Araucania with IV in Lautaro and Vilcun and III in Temuco and Villarrica. GUC reported this earthquake was felt with intensity V in  Los Lagos at Osorno, Puerto Montt, Puerto Octay, Purranque, Rio Negro, San Juan de la Costa, San Pablo; IV in Puerto Varas, Ancud, Fresia, III in Castro, Maullin, Puyehue and Quellon; in Los Rios with V in Corral, Los Lagos, Valdivia; IV in La Union, Lago Ranco, Mafil, Mehuin, Paillaco, Panguipulli, Rio Bueno and III in Futrono, and Mariquina; in Araucania with VI in Padre lsa Casas and Temuco, V in Teodoro Schmidt, Tolten, Vilcun, Villarrica, Angol, Carahue, Gorvea, Loncoche, Pitrufquen; IV in Victoria, Cunco, Curacautin, Curarrehue, Melipeuco, Nueva Imperial Pucon, Puren, III in Lumaco, Ercilla; in Biobio with V in Tirua; IV in Los Angeles and III in Chiguayante, Concepcion, Hualpen, Lebu, Nacimiento, Talcahuano and Tucapel and with V in Yungay, Nuble, Chile. Aftershocks were also felt in Los Lagos with moderate intensity.

 

Today's M 6.7 in Chile was preceded by several precursory events as outlined in this summary in the previous issue:

 

 

"An unusual earthquake occurred northwest of New Zealand today with M 4.8.  This is the strongest earthquake within about 300 km of this epicenter in at least 30 years. Previous earthquakes in this region have often  occurred within hours or days of strong earthquakes in southern Chile as discussed in this summary on February 24-25, 2010, ten years ago, several days before an M 8.8 in Central Chile" (December 26-27, 2020)

 

and

 

"According to data on NASA's Solar Eclipse page, the maximum solar eclipse of December 14, 2020 occurred at 40S 68W. A series of events in the area of Aisen Chile was reported in this summary yesterday as:

 

"A series of moderate earthquakes hit the area of Aisen, Chile today including an M 4.7. This epicenter saw the complete solar eclipse on December 14, 2020. Hudson Volcano is in this region and these may be related to upcoming volcanism at that volcano. This volcano saw one of the largest eruptions of the 20th century from August to October 1991 (Plinian VEI 5) and may be preparing for a moderate follow-up eruption. The only earthquake within about 200 km of today's epicenter with M>=4.7 in the past year was an M 5.2 on April 1, 2020. But this event is south of current moderate activity in this region. The last event of M>=4.7 south of 46 degrees south latitude was an M 5.0 on December 22, 2011." (December 25-26, 2020)

 

If a strong earthquake is to occur in Chile in the next several days, it would most likely occur in the area near where the eclipse was maximized." (December 26-27, 2020)

 

The NASA solar eclipse page shows the total eclipse was visible at the epicenter of today's quake. It was observed for 2 minutes 8 seconds at the epicenter  at 16:00 UT (noon local time). Maximum eclipse occurred about 200 km southeast of this and lasted for 2 minutes 9 seconds. The precision between this epicenter and the maximum eclipse location is remarkable.

 

Today's M 6.7 is the largest within about 200 km of this epicenter since an M 7.4 aftershock of the M 8.8 on February 27, 2010 while the only event within about 150 km of today's epicenter with M>=6.7 was an M 6.7 on April 1, 1998. Forecast 129861 had expected today's activity in Central Chile was likely around December 24. Today's activity is at the third node (120 degrees) from both the earthquakes of M 7.6 in the Alaska Peninsula of October 19 and the M 7.0 in the Dodecanese Islands of October 30 and was probably promoted by energy from those sources.

 

O: 27DEC2020 21:39:15  39.3S   74.9W Mw=6.7  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 28DEC2020 00:09:00  39.3S   75.1W mb=4.4  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 27DEC2020 22:19:08  39.2S   75.1W mb=4.8  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 27DEC2020 22:02:36  39.4S   75.2W mb=4.3  EMSC   OFF COAST OF LOS LAGOS, CHILE

O: 27DEC2020 21:39     39.3S   74.8W mb=6.7  GUC    Los Lagos at Osorno, Puerto Mo

P: 24DEC2020 129861    37.0S   73.0W 4.0-5.3 BCBAA  Central Chile              

 

A pair of earthquakes of M 5.2 each also occurred in Croatia today. NEIC reported they were felt with damage in Croatia at Moscenica and Sisak (VII) and Petrinja and Glina (VI); V shaking was observed in Lekenik, Gradici; IV in Potok, Odra with lesser intensity in Kriz, Zagreb and Bosnia and Herzegovina. These epicenters are at 118 degrees (near node 3) from the quake in Los Lagos and may have been promoted by energy from that source. The only earthquake in the region of Croatia within about 200 km of today's activity in the past 30 years occurred about 50  km northwest of today's epicenter with M 5.4 on March 22,  2020. Forecasts 129746 and 129755 had expected today's activity was likely around December 24.

 

O: 28DEC2020 05:28:07  45.4N   16.2E mb=5.2  EMSC   CROATIA

O: 28DEC2020 06:49:56  45.4N   16.3E mb=5.0  EMSC   CROATIA                      

P: 24DEC2020 129746    44.0N   18.0E 3.0-4.8 BBAAA  Adriatic Sea               

P: 24DEC2020 129755    43.0N   16.0E 3.0-5.1 BCAAA  Italy                      

 

An M 3.8 and aftershocks were lightly felt in northern California today. The M 3.8 was reported felt with maximum intensity IV in California at Princeton and III in Butte City, Glenn, Durham, Biggs, Hamilton City, Willows, Colusa, Chico and Gridley. An M 4.2 hit this area on August 19, 2020 with an aftershock of M 3.8 on October 20, 2020. Today's epicenter is at the fourth node (90 degrees) from the M 6.7 in Chile today. Forecast 129693 had expected activity in this area was likely enhanced around December 29.

 

O: 27DEC2020 14:06:36  39.4N  123.3W Md=2.1  EMSC   NORTHERN CALIFORNIA          

O: 27DEC2020 14:59:47  39.5N  122.0W Md=2.5  EMSC   NORTHERN CALIFORNIA

O: 27DEC2020 14:44:37  39.5N  122.1W mb=3.8  EMSC   NORTHERN CALIFORNIA          

P: 29DEC2020 129693    39.2N  123.1W 2.5-4.4 AAAAA  Central California         

 

MODERATELY STRONG QUAKES IN EASTERN TURKEY AND CENTRAL PERU

 

EARTHQUAKE SUMMARY FOR DECEMBER 26, 2020

 

An earthquake of M 5.7 was widely felt in central Peru today. NEIC reported it was felt with maximum intensity VI in Acari, Arequipa and V in Nazca, Peru with lesser shaking in Ica. Similar to the earthquakes in Luzon and Mindoro, Philippines of the past several days, this epicenter is located on the geomagnetic equator and was probably promoted by the recent geomagnetic storm, the strongest in the past month as previously noted in this summary as:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 10.  High latitude geomagnetic field also saw disturbed conditions with AP 20. This is the strongest disturbance in the geomagnetic field in a month - since AP reached 24 on November 22, 2020. Moderate increases in seismicity at high latitudes and near the geomagnetic equator may follow in the next several days, depending on the strength of this storm." (December 23-24, 2020)

 

This is the strongest earthquake within about 200 km of this epicenter since an M 5.8 on May 5, 2019. A major earthquake of M 8.4 hit near this epicenter on  June 23, 2001 with a solar eclipse visible in the area. This had been noted in this summary when a smaller foreshock to today's event occurred on December 16, 2020 with M 5.6 and may be an aftershock of that event. At the time this summary noted the relation to the solar eclipse as:

 

 

"A major earthquake occurred on June 23, 2001 in southern Peru about two days after a solar eclipse was observed in the area. The HISTORY section of this report details that event as:

 

 6 23 20 33 14 2001 -16.265  -73.641  33 8.4   Near the coast of Peru          

 

Today's earthquake was near the epicenter of that in June 2001 and occurred several days after the solar eclipse, as did the previous. The area may be particularly sensitive to tidal effects. Today's event occurred within about an hour of local solar noon, a time when tidal stresses maximize. The last earthquake within about 200 km of today's epicenter with M>=5.6 was an M 6.0 on July 17, 2013. Most activity in this area occurs about 200 km to the west of today's epicenter. The last within 300 km was an M 7.1 on January 14, 2018." (December 17, 2020)

 

Forecast 129836 had expected today's event within about 100 km was likely around December 24. This epicenter is at 101 degrees from the Alaska Peninsula quake of M 7.6 of October 19, 2020 and may have been promoted by energy from that source.

 

O: 27DEC2020 07:11:11  16.1S   74.3W Mw=5.7  EMSC   NEAR COAST OF SOUTHERN PERU  

P: 24DEC2020 129836    17.0S   74.0W 4.0-5.3 BAAAA  So. Peru/Bolivia           

 

An M 5.5 also occurred today in eastern Turkey. It was reported strongly felt with intensity VIII in Sivrice and VII in Elazig, Turkey with IV in Malatya and Diyarbakir, Turkey. Lesser intensity of III was reported from Yesilyurt, Malatya and Fethiye, Mugla, Turkey. A foreshock of M 4.1 was felt in the area with VII in Sivrice, Elazig and V in Yozgat and III in Diyarbakir. A strong earthquake of M 6.7 hit this area on January 24, 2020 and has been followed by moderate aftershocks of M 5.9 on June 14, 2020 and M 5.6 on August 4, 2020. Today's event is likely an aftershock of the January quake. Forecast 129741 had expected today's event was likely around December 31.

 

O: 27DEC2020 06:37:32  38.5N   39.2E Mw=5.5  EMSC   EASTERN TURKEY               

O: 26DEC2020 11:09:20  38.5N   39.2E ML=4.1  EMSC   EASTERN TURKEY

P: 31DEC2020 129741    39.0N   40.0E 3.5-4.9 BAAAA  Turkey                      

 

An unusual earthquake occurred northwest of New Zealand today with M 4.8.

This is the strongest earthquake within about 300 km of this epicenter in at least 30 years. Previous earthquakes in this region have often  occurred within hours or days of strong earthquakes in southern Chile as discussed in this summary on February 24-25, 2010, ten years ago several days before an M 8.8 in Central Chile as:

 

"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. These included events in the Andaman Islands of India and Chiapas, Mexico, right where activity was high today." (February 24, 2010)

 

and

 

"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 the great M 9.3 earthquake in Sumatra on December 26, 2004 which triggered a tsunami and killed more than 200,000 people around the Indian Ocean. It is the strongest earthquake in the western Hemisphere since in the 46 years since the Good Friday earthquake of March 28, 1964 in Anchorage, Alaska." (February 28, 2010)

 

This epicenter is at 145 degrees from the Dodecanese Islands quake of M 7.0 of

October 30, 2020 and may have been promoted by energy from that source.

 

O: 24FEB2010 11:58:02  30.3S  165.8E ML=5.3  NEIC    NORTHWEST OF NEW ZEALAND    

 

According to data on NASA's Solar Eclipse page, the maximum solar eclipse of December 14, 2020 occurred at 40S 68W. A series of events in the area of Aisen Chile was reported in this summary yesterday as:

 

 

"A series of moderate earthquakes hit the area of Aisen, Chile today including an M 4.7. This epicenter saw the complete solar eclipse on December 14, 2020. Hudson Volcano is in this region and these may be related to upcoming volcanism at that volcano. This volcano saw one of the largest eruptions of the 20th century from August to October 1991 (Plinian VEI 5) and may be preparing for a moderate follow-up eruption. The only earthquake within about 200 km of today's epicenter with M>=4.7 in the past year was an M 5.2 on April 1, 2020. But this event is south of current moderate activity in this region. The last event of M>=4.7 south of 46 degrees south latitude was an M 5.0 on December 22, 2011." (December 25-26, 2020)

 

If a strong earthquake is to occur in Chile in the next several days, it

would most likely occur in the area near where the eclipse was maximized.

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the Fox Islands, Aleutians, Alaska. An M 6.4 hit this area on December 1, 2020 and this is probably a regional aftershock of that event. Forecast 129797 had expected today's event within about 25 km was likely around December 29.

 

O: 27DEC2020 04:45:26  52.5N  169.6W mb=4.2  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 29DEC2020 129797    52.5N  169.2W 3.5-4.8 AAAAA  Fox Islands, Aleutians     

 

MODERATE REGIONAL AFTERSHOCK IN LUZON, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR DECEMBER 25, 2020

 

The strongest earthquake in the world today was an M 5.4-5.5 in Luzon, Philippines. It appears to be a regional aftershock of the M 6.3 which hit Mindoro, Philippines yesterday. Today's event was reported felt with intensity V in Aurora, San Francisco, Quezon, Southern Tagalog and III in Boac and Baguio, Cordillera. The last earthquake of M>=5.5 within about 150 km of this epicenter was an M 5.7 on November 5, 2010 more than 10 years ago. AnM 5.6 hit about 150 km southeast of this on March 5, 2012. Forecast 129646 had expected activity in Luzon was likely around December 31. This epicenter is at the fifth node (72 degrees) from  the epicenter of the M 7.6 in the Alaska Peninsula of October 19, 2020 and was probably promoted by energy from that source.

 

O: 25DEC2020 10:04:37  13.3N  122.3E Mw=5.4  EMSC   LUZON, PHILIPPINES           

O: 25DEC2020 10:04:37  13.3N  122.3E Mw=5.5  ANSS   LUZON, PHILIPPINES           

P: 31DEC2020 129646    11.0N  126.0E 3.5-5.0 CCCAA  Luzon, Philippines         

 

A series of moderate earthquakes hit the area of Aisen, Chile today including an M 4.7. This epicenter saw the complete solar eclipse on December 14, 2020. Hudson Volcano is in this region and these may be related to upcoming volcanism at that volcano. This volcano saw one of the largest eruptions of the 20th century from August to October 1991 (Plinian VEI 5) and may be preparing for a moderate follow-up eruption. The only earthquake within about 200 km of today's epicenter with M>=4.7 in the past year was an M 5.2 on April 1, 2020. But this event is south of current moderate activity in this region. The last event of M>=4.7 south of 46 degrees south latitude was an M 5.0 on December 22, 2011.

 

O: 26DEC2020 03:53:20  46.2S   76.6W ML=4.0  EMSC   OFF COAST OF AISEN, CHILE

O: 26DEC2020 00:22:23  46.3S   76.7W ML=3.9  EMSC   OFF COAST OF AISEN, CHILE

O: 26DEC2020 01:46:57  46.4S   76.4W ML=4.2  EMSC   OFF COAST OF AISEN, CHILE

O: 26DEC2020 02:23:16  46.5S   76.0W ML=4.0  EMSC   OFF COAST OF AISEN, CHILE

O: 26DEC2020 02:19:32  46.2S   75.5W mb=4.7  EMSC   NEAR COAST OF AISEN, CHILE   

 

An M 2.8 in the Canary Islands sequence today was the largest in the current swarm in that area since it began on December 20 with an M 3.1. Smaller events followed and this swarm does not appear to have reached its peak yet.

 

O: 26DEC2020 01:28:59  28.5N   17.4W mb=2.8  EMSC   CANARY ISLANDS, SPAIN REGION 

 

The strongest earthquake in the U.S. or Canada today was an M 4.3-4.5 in the Vancouver British Columbia region of Canada. It was reported lightly felt in the area and may have had a light aftershock of M 4.1 according to Earthquakes Canada. The last earthquake reported with M>=4.5 in this region was an M 5.2 on May 23, 2020. A series of earthquakes including an M 6.3 and 6.0 occurred in the region on December 23 and December 25, 2019, exactly one year ago. There is a statistical significance to events recurring one year apart which may be related to recurring weather phenomena. Forecast 129792 had expected today's event was likely within about 50 km of this epicenter around December 27.

 

NEIC reported this earthquake of M 4.3 in Vancouver, British Columbia, Canada was felt with intensity II-III in the area(s) of Vancouver, British Columbia, Canada.

 

O: 25DEC2020 17:13:51  50.9N  129.4W MB=4.1  ECAN OF PORT HARDY, BC              

O: 25DEC2020 17:13:48  50.5N  130.3W MB=4.5  ECAN Port Hardy, BC                 

O: 25DEC2020 17:13:49  50.7N  130.0W mb=4.3  EMSC   VANCOUVER ISLAND, CANADA REGIO

P: 27DEC2020 129792    50.9N  130.6W 3.0-4.8 AAAAA  British Colombia           

 

An active aftershock sequence occurred today following an M 3.6 in Southern California. NEIC reported this earthquake of M 3.6 in  Southern California was felt with intensity II-III in the area(s) of  Southern California in Coachella, Indio, La Quinta, Palm Desert, Thousand Palms, Palm Desert, Rancho Mirage, Cathedral City and Desert Center. NEIC reported an earthquake of M 2.7 in Southern California was felt with intensity II-III in the area(s) of Southern California at Mountain Center. This epicenter is north of much of the recent activity in the region and is the first significant swarm of quakes within about 50 km since May 30, 2015 which included events of M 3.7 and 3.8. The only similar quake in the area in the past five years was an M 4.2 on July 22, 2019. Forecast 129451 had expected activity in this area was likely around December 20. This epicenter is located at 102 degrees from the Dodecanese Islands where the last major earthquake of M 7.0 occurred on October 30, 2020 and was probably promoted by energy from that source.

 

O: 25DEC2020 20:25:58  33.7N  115.9W Mw=3.6  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 10:24:28  33.8N  115.9W ML=2.0  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 11:41:05  33.8N  115.9W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 14:01:02  33.8N  115.9W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 20:41:22  33.8N  115.9W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 20:58:52  33.8N  115.9W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 23:01:03  33.8N  115.9W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 25DEC2020 23:34:15  33.8N  115.9W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 26DEC2020 00:27:01  33.8N  115.9W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

P: 20DEC2020 129451    33.5N  116.7W 2.5-4.3 BAAAA  So. California             

 

O: 25DEC2020 15:22:04  33.7N  116.7W Ml=2.6  EMSC   SOUTHERN CALIFORNIA          

P: 20DEC2020 129451    33.5N  116.7W 2.5-4.3 BAAAA  So. California             

 

NEIC reported this earthquake of M 2.6 in Idyllwild, California was felt with intensity II-III in the area(s) of Idyllwild, Mountain Center, Palm Springs, Palm Desert and San Jacinto, California.

 

STRONG QUAKE SHAKES MANILA, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR DECEMBER 24, 2020

 

A strong M 6.3 was widely felt in the Luzon region of Central Philippines today. NEIC reported maximum intensity VI in Southern Tagalog at Calatagan and Tagaytay; IV in Luksuhin, Santa Clara, Indang, Malabaf and Maragondon and II-III in San Pascual, Calantas and Nasugbu. PHIVOLCS reported this event at M 6.3 was felt with intensity VI in Lubang, Occidental Mindoro;i V in Calatagan, Balayan, Nasugbu, Batangas City, Calaca and San Luis, Batangas; Looc, Occidental Mindodo; Tagaytay City, Amadeo, Indang, Kawit and Alfonso, Cavite; Binan, Laguna and IV in Abra de llog and Paluan, Occidental Mindoro, Taal, San Jose San Pascual, Lemery Malvar and Ibaan, Batangas; Maragondon and Carmona; Cavit; San Pedro, Laguna; City of anila, Marikina City; Quezon City, Cainta San Mateo and Antipolo City, Rizal, Pasig City; Makati City; La Pinas City; Pateros, Obando, Malolos and Meycauyan, Bulacan; Subic and San Felipe, Zambales; Alaminos, Pangasinan, Santo Tomas, La Union; City of Mabalacat, Pampanga and with lesser intensity in Quezon and Mindoro, Philippines. There were no immediate reports of major damage or casualties and no tsunami was reported generated. This is the strongest earthquake recorded within about 250 km of this epicenter since an M 6.4-6.5 on October 8, 2004 about 20 km northwest of today's epicenter and near the same depth (105 km). At the time this summary reported on this event as:

 

"... in Mindoro Province of the Philippines.  The earthquake caused high rise buildings in Manila to sway and knocked out power in many areas according to the Associated Press. The epicenter occurred west of Tagaytay City south of Manila according to the Philippine Institute of Volcanology and Seismology. Maximum intensity of V was reported from Puerto Galera, Oriental Mindoro on Luzon. Residents rushed into the streets of Manila in panic and the major thoroughfares of Manila suffered traffic jams as vehicles stopped in the middle of the road. This is the second earthquake  of M>=6 along this area of the Manila Trench since an M 6.0 occurred to the north west on Sept. 15, 2004 three weeks ago. This is the strongest event in the region of central Philippines (12-17N 120-126E) since an M 7.2 hit about 350 km to the east on June 11, 1996." (October 8, 2004)

 

Today's epicenter is located on the geomagnetic equator and the earthquake was likely promoted by geomagnetic effects related to the current geomagnetic storm, the strongest in more than a month as reported in previous issues of this summary:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 10.  High latitude geomagnetic field also saw disturbed conditions with AP 20. This is the strongest disturbance in the geomagnetic field in a month - since AP reached 24 on November 22, 2020. Moderate increases in seismicity at high latitudes and near the geomagnetic equator may follow in the next several days, depending on the strength of this storm." (December 23-24, 2020)

 

Forecast 129649 had expected today's event in central Philippines to the north of today's epicenter was likely around December 24. Today's earthquake in the

Philippines is located at the fifth node (72 degrees) from the M 7.6 in the

Alaska Peninsula of October 19, 2020 the last major event of M>7 in the world, and may have been promoted by energy from that source. It is also at twice this distance (144 degrees) from the M 6.7 in the Central Mid-Atlantic of September 18, 2020 and may have been promoted by energy from that source.

 

O: 24DEC2020 23:43:42  13.8N  120.6E Mw=6.3  EMSC   MINDORO, PHILIPPINES         

P: 24DEC2020 129647    18.0N  120.0E 3.5-4.8 ACAAA  Luzon, Philippines         

 

A series of moderate earthquakes also were widely felt in southern Puerto Rico today. The strongest of these were M 4.7-4.9 and were reported felt with maximum intensity VI in Guayanilla and V in Guanica and Yauco with IV at Ponce, and II-III in Penuelas, Lajas and San German. The M 4.8 was felt with intensity up to VII (minor damage) in Puerto Rico at Guanica and VI in Guayanilla with IV in Ensenada, Yauco, Penuelas, Sabana Grande, Ponce, Lajas. These continue a trend in recent years for moderate quakes in Puerto Rico near the end of December. An M 4.1 was felt with intensity IV in Guayanilla and San German and III in Ciales, Puerto Rico. Following is a listing of events of M>=4 in Puerto Rico today. A more complete listing of M>=3 can be found in the "AMERICA" section of this summary. Forecast 129659 had expected today's activity was likely around December  24-25. The last earthquake of larger size in the southern Puerto Rico aftershock zone was an M 5.3 more than half a year ago on July 3, 2020. A series of foreshocks of M 4.7, 4.7 and 5.0 hit the area on December 28-29, 2019 prior to the mainshock of M 6.4 on January 7, 2020.

 

O: 24DEC2020 11:16:59  17.8N   66.8W ML=4.0  EMSC   PUERTO RICO REGION

O: 24DEC2020 16:56:38  17.9N   66.8W Mw=4.8  ANSS   PUERTO RICO REGION

O: 24DEC2020 16:56:38  17.9N   66.8W Mw=4.7  EMSC   PUERTO RICO REGION

O: 24DEC2020 17:33:46  17.9N   66.8W Mw=4.4  EMSC   PUERTO RICO REGION

O: 24DEC2020 17:33:47  17.9N   66.8W Mw=4.7  ANSS   PUERTO RICO REGION

P: 24DEC2020 129659    18.0N   66.0W 3.4-4.9 AAAAA  Puerto Rico                

P: 25DEC2020 129659    19.0N   67.0W 3.4-4.8 AAAAA  Puerto Rico                

 

Moderate eruptions continued today in Kilauea, Hawaii. The largest earthquakes associated with these were M 3.5 and 3.6. NEIC reported these were felt with intensity II-III in Hawaii at Pahala, Naalehu, Volcano, Captain Cook, Mountain View, Hilo, Holualoa, Kurtistown, Paauilo, Hawaii National Park, Pahala, Kailua Kona, Kamuela and Hakalau.  Forecast 129643 had expected this activity within about 25 km was likely  around December 23. Recent earthquakes in Hawaii of M>=4.2 occurred with M 4.4 on December 21, 2020 starting the current eruption and with the solar eclipse of December 14, 2020 and with M 4.7 on July 3, 2020 and July 27, 2020.

 

 

O: 25DEC2020 05:13:14  19.3N  155.4W ML=4.1  EMSC   ISLAND OF HAWAII, HAWAII     

O: 25DEC2020 05:18:25  19.3N  155.4W ML=4.2  EMSC   ISLAND OF HAWAII, HAWAII     

P: 23DEC2020 129643    19.2N  155.2W 3.0-4.3 AAAAA  Hawaii                     

 

Light earthquakes also continued in the Canary Islands of Spain today. This may

be a failed attempt at a volcanic eruption at Teniriffe Volcano. This series

has been ongoing for the past three days. The last earthquake of M>=2.1 in the

Canary Islands was an M 5.4 on December 27, 2013 after a swarm hit the area on

December 23-24, 2013. At the time this summary reported on this as:

 

"A series of light earthquake began hitting the Canary Islands today. This appears to be a reinvigoration of the eruptive status of El Hierro Volcano and bears watching. This appears to have begun about the time of the full moon and tidal effects may have been an initiating effect. It is also likely that these earthquake were prompted by the renewed solar flare  activity which began at the same time these small events began in the Canary Islands." (December 23, 2013)

 

"The swarm under El Hierro volcano in the Canary Islands continued at a reduced rate today. A volcanic eruption does not seem imminent in this region but

 a strong storm, solar flare or geomagnetic storm combined with strong astronomical tides could intensify this pre-eruption sequence." (December 25, 2013)

 

This earthquake is the strongest since volcanic activity began in 2011. It caused damage to buildings and rock slides but no injuries. Two roads were closed due to rock falls blocking them. A sudden elevation and the previous earthquakes caused local scientists to issue a warning raising the volcano alert level to yellow hours before this earthquake. Strong earthquakes such as this  can lead to subsequent eruptions as they move materials around often opening vents for magma to reach the surface. Residents reported strong shaking and the quake was felt throughout the Canary Islands.

 

This is the strongest earthquake recorded in the past 25 years in the Canary Islands. The largest (and only) previous earthquake recorded within 250 km of this  epicenter of M>=5.4 occurred on May 22, 1964 with M 5.5. There has been some concern that sliding blocks, perhaps triggered by an earthquake of this size or larger, could slide from the volcanic slopes into the sea generating an Atlantic-wide tsunami." (December 25-27, 2013)

 

Following is a listing of events of M>=2 in the Canary Islands today.

 

O: 24DEC2020 09:29:18  28.5N   17.9W ML=2.2  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 21:04:26  28.5N   17.9W ML=2.1  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 21:06:19  28.5N   17.9W ML=2.0  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 07:01:59  28.6N   17.9W ML=2.1  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 11:12:25  28.6N   17.8W ML=2.2  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 15:26:06  28.6N   17.9W ML=2.2  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 21:10:02  28.6N   17.8W ML=2.0  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 21:29:17  28.6N   17.8W ML=2.1  EMSC   CANARY ISLANDS, SPAIN REGION

O: 24DEC2020 12:45:38  27.8N   15.2W ML=2.2  EMSC   CANARY ISLANDS, SPAIN REGION 

P: 14DEC2020 129394    28.0N   16.0W 3.0-4.4 CAAAA  Canary Islands             

 

The activity in the Canary Islands is at the fourth node (90 degrees) from the M 7.6 in the Alaska Peninsula of October 19 and may have been promoted by energy from that source.