STRONG EARTHQUAKE SHAKES NORTHERN INDIA

 

EARTHQUAKE SUMMARY FOR APRIL 23, 2019

 

The strongest earthquake in the world today was an M 5.9-6.0 in northern India. NEIC reported maximum intensity in Arunachal Oradesh at Along with IV; V in Pasighat, Dhemaji, Chapua and Tinsukia, Assam, and IV in Basar, Arunachal Pradesh and in Assam in Dibrugarh, Barbari, Makum and Dum Duma, India.  IMD reported this earthquake was felt with intensity V in Arunachal Pradesh, India at Dibrugarh, IV in Dimapur, Nagaon, III in Guwahati and Imphal. While some panic occurred with residents, no major damage or casualties were reported with today's event. A second quake, perhaps a regional aftershocks hit the Medog county in Nuingchi City near Arunachal Pradesh in Tibet.  NEIC reported this earthquake of M 4.7 in Nepal was felt with intensity V in Nepal at Bidur, Nuwakot; IV in Kirtipur, Kathmandu, Lalitpur, Tribuvannagar and Bhaktapur and II-III in the area(s) of Pokhara, Tansen, Janakpur and Damak, Nepal.  IMD reported this earthquake was felt with intensity  IV in Northern India at Battiah, Motihan, Riga, Sheohar and III in Patrauna.

 

IMD (India Meteorological Department) gave the event M 5.9 while other teleseismic reporters gave slightly higher magnitudes. The mainshock occurred near local solar midnight and may have been promoted by strong tidal stresses.   

 

The last earthquake with M>=5.8 in the Arunachal Pradesh area of India within about 200 km of this epicenter was an M 6.3 on November 17, 2017 and prior to that an M 6.1 on September 21, 2009 - the only such events in the region in the past 30 years. Forecast 115372 had expected moderate activity within this region between April 24 and 26.

 

O: 23APR2019 20:15:50  28.5N   94.6E Mw=5.9  EMSC   ARUNACHAL PRADESH, INDIA     

O: 23APR2019 20:15:48  28.6N  094.4E MS=5.8  IMD  Felt with intensity V in Arunachal Pradesh

P: 24APR2019 115372    24.0N   94.0E 4.0-5.4 ACAAA  Myanmar                    

P: 26APR2019 115372    27.0N   97.0E 4.0-5.4 BBBAA  Myanmar                    

 

O: 24APR2019 00:44:32  27.9N   85.1E mb=4.7  EMSC   NEPAL                        

O: 24APR2019 00:44:33  27.7N  085.1E MS=4.9  IMD  Felt with intensity  IV

P: 29APR2019 115374    27.0N   88.0E 3.5-5.4 BACAA  Nepal                      

 

A strong earthquake of 5.9-6.0 also occurred in the region south of the Fiji Islands today. This is a remote area and this event was not reported felt. Forecast 115549 had expected it within about 100 km of the epicenter was likely around April 26. The last earthquake within about 200 km of this epicenter with M>=6.0 occurred as an M 6.9 on February 24, 2017 with M 6.9. This epicenter is located at 102 degrees from the M 7.0 in Peru of March 1 and the M 7.5 in Ecuador of February 22 and may have been promoted from those sources.

 

O: 23APR2019 15:22:54  23.9S  180.0W mb=4.6  EMSC   SOUTH OF FIJI ISLANDS        

O: 23APR2019 14:20:14  24.9S  178.8W Mw=5.9  EMSC   SOUTH OF FIJI ISLANDS        

O: 23APR2019 14:20:17  24.7S  178.8W mw=6.0  ANSS   the Fiji Islands

P: 26APR2019 115549    25.0S  179.0W 4.0-5.5 BAAAA  Tonga Islands              

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the current aftershock sequence in north-western Alaska. It was accompanied by foreshocks and aftershocks of M 3.6 and 3.4 and 3.8. The M 4.4 is the strongest aftershock of the sequence which began on October 14, 2018. The last such event in the area was an M 5.2 on March 26, 2019. Forecast 115483 had expected today's activity was likely around April 24.

 

O: 23APR2019 15:38:57  66.3N  156.9W ml=3.4  EMSC   NORTHERN ALASKA              

O: 24APR2019 02:40:02  66.3N  157.0W mb=3.8  EMSC   NORTHERN ALASKA              

O: 23APR2019 13:39:51  66.3N  157.2W ML=3.6  EMSC   NORTHERN ALASKA              

O: 23APR2019 15:32:43  66.3N  157.2W Mw=4.4  EMSC   NORTHERN ALASKA              

P: 24APR2019 115483    65.7N  156.9W 3.5-5.1 AAAAA  Northern Alaska            

 

Seismicity continued in the Mayotte area east of Africa. This is probably related to the passage of Tropical Cyclone Kenneth which passed over this epicenter about the time of this earthquake as noted in previous issues  of this summary:

 

"TC Kenneth (24S) formed today east of the Comoros Islands with winds up to 90 kts. It is expected to track to the west over Mayotte in the next day. Some seismicity may be enhanced in the region of Mayotte. The antipode at 11N 145W is south of  Hawaii, and some seismicity may be promoted in Hawaii as this storm moves west." (April 23-24, 2019)

 

A similar event hit the region yesterday. Forecast 115248 had expected this activity was likely around April 18.

 

O: 23APR2019 22:35:36  12.8S   45.4E mb=4.6  EMSC   MAYOTTE REGION               

P: 18APR2019 115248    14.0S   44.0E 3.0-4.4 BBBAA  Madagascar area            

 

DEADLY EARTHQUAKES STRIKE AT CENTRAL PHILIPPINES

 

EARTHQUAKE SUMMARY FOR APRIL 22, 2019

 

Global seismic quiet came to an end today with earthquakes of M 6.1 and 6.4 in the Central Philippines; an M 6.0 in the South Sandwich Islands and moderately large events of M 5.4-5.6 in Vancouver, British Columbia, Canada; off the coast of northern Honshu, Japan and in Oaxaca, Mexico. Seismicity in California also  showed a moderate increase at this time with an M 3.9 in the Imperial Valley region of southern California.

 

A pair of strong earthquakes of M 6.1 and 6.4 hit the Luzon, Central Philippines about 60 km NW of Manila and Samar Island, Leyte today. Initial reports indicated the first of these killed at least 16. Five people died when a five-story supermarket collapsed (pancaked) on the store. Electricity was cut to prevent fires.  Many people were crushed beneath collapsing building in the Pampanga Province and at least 24 are still missing. Landslides block roads as boulders rolled down mountain sides and most public transportation was suspended. The second earthquake in Samar was reported to have damaged homes and roadways as well. This event was located about 75 km from Tacloban City, which has a population of about a quarter million. In Samar, at least five houses were destroyed in the city of Catbalogan. Three dams in the Central Philippines sustained damage. No tsunami was expected nor observed with either of these earthquakes.

 

While the earthquake in Samar was probably triggered by stress redistribution following the Luzon quake, tidal promotion cannot be completely dismissed.  The Samar earthquake occurred new local solar noon when tidal stresses maximize. It also occurred at 11N latitude when the sun was directly overhead at local solar noon (subsolar). This enhanced vertical stresses and probably helped promote the second earthquake as noted in previous issues of this report:

 

"The full moon arrived at 11:12 UT on April 19, 2019. Longitudes which were sub-solar at this time were near 15 East and 165 West. These include areas of central and western Europe in the east and the Aleutian Islands and western Alaska in the West. Other areas which may see enhanced tidal promotion at this time are the Kermadec-Tonga arc north to Samoa. While these regions will experience maximum stress from the tidal alignment, many other areas could see enhanced seismicity in the next five days and a strong earthquake is likely in this time period." (April 19-22, 2019)

 

NEIC reported major damage in the Luzon quake with intensity up to IX. VIII was reported from Central Luzon at Del Carmen with VII in Bodega, Calangain, Guta, Hermosa, Lubao and VI in San Benito, Irani and San Basilio, Central Luzon and as far as 150 km from the epicenter with intensity up to IV. PHIVOLCS reported it was felt with intensity VI - San Marcelino, and Subic, Zambales; Floridablanca, Lubao, and Porac, Pampanga; Angeles City; Olongapo City; Intensity V - Castillejos, and San Felipe, Zambales; Magalang, Mexico, and San Fernando, Pampanga; Abucay, Balanga, and Mariveles, Bataan; Malolos, and Obando, Bulacan; Indang, Cavite; Lipa City; Makati City; Mandaluyong City; Manila City; Quezon City; Pasay City; San Juan City; Taguig City; Tarlac City; Valenzuela City; Intensity IV - Meycauayan, Plaridel, and San Jose Del Monte, Bulacan; San Rafael, Tarlac; Rosales and Villasis, Pangasinan; Itogon, and La Trinidad, Benguet; Kasibu, Nueva Vizcaya; Gabaldon, Nueva Ecija; San Mateo, Rizal; Bacoor, Imus, and Maragondon, Cavite; Nasugbu, Batangas; Antipolo City; Baguio City; Caloocan City; Las Pi¤as City; Marikina City; Pasig City; Tagaytay City; Intensity III - Marilao, Bulacan; Santo Domingo, and Talavera, Nueva Ecija; Maddela, Quirino; Dingalan, Aurora; Lucban, Quezon; Santa Cruz, Laguna; Carmona, Dasmari¤as, General Trias, and Silang, Cavite; San Nicolas and Talisay, Batangas; Cabanatuan City; Calamba City; Gapan City; Muntinlupa City; Palayan City; Intensity II - Baler, Aurora; Philippines.

 

This was the strongest shallow focus earthquake within about 150 km of Manila and this epicenter since an M 6.2 on October 9, 2003. Intermediate focus events of M 6.1-6.4 hit this area on August 11, 2017 and October 8, 2004 (M 6.2 and 6.4).  Forecast 115059 had expected this activity was likely in mid-April.

 

O: 22APR2019 09:11:11  14.9N  120.5E Mw=6.1  EMSC   LUZON, PHILIPPINES           

O: 22APR2019 09:11:11  14.9N  120.5E mw=6.1  ANSS   ESE of Gutad Philippines

O: 22APR2019 09:11:09  15.2N  120.3E MS=6.1  PHI  Felt with intensity VI

P: 17APR2019 115059    13.0N  122.0E 3.5-5.0 BBBAA  Luzon, Philippines         

 

NEIC reported maximum intensity in the Samar earthquake of VIII (major damage) was felt in Baras, Paranas and Jiabong, with VI in Borongan, Silanga, San Antonio, San Policarpio and Pawing with V in Palo and IV in Catbalogan, Eastern Visayas, Philippines. PHIVOLCS reported the M 6.5 was felt with intensity VI - San Julian, Eastern Samar; Intensity V - Tacloban City; Catbalogan City, Samar; Gen. Mc Arthur, Salcedo and Guiuan Eastern Samar; Naval, Biliran; Catarman, Northern Samar; Palo and Pastrana, Leyte; Intensity IV - Abuyog, Hilongos, Javier, Capoocan, Julieta, Baybay, Barogo, Jaro, MacArthur, Matalum, Villaba, Leyte; San Francisco, Southern Leyte; Bislig City, Surigao Del Sur; Iloilo City; Naga City; Sorsogon City; Panganiban, Catanduanes; Intensity III - Binalbagan, Negros Occidental; Cabalian, Southern Leyte; Dimasalang, Masbate; Butuan City; Cabadbaran City; Intensity II - Bago City; Bacolod City; Samar, Philippines.

An aftershock of 4.6 was reported by PHIVOLCS to have been felt with intensity II in Catarman, Northern Samar; Leyte, Leyte, Philippines.

 

The last earthquake in Samar within about 150 km of this epicenter with M>=6.5 occurred on April 21, 1995 with M 6.8 and 7.1. An M 6.5 hit the area northeast of this on November 18, 2003.  Forecast 115059 had expected today's activity around April 16.

 

O: 23APR2019 06:41:14  11.7N  125.2E mb=4.8  EMSC   SAMAR, PHILIPPINES           

O: 23APR2019 05:37:51  11.8N  125.3E MS=6.5  PHI  Felt with intensity VI

O: 23APR2019 06:41:12  11.9N  125.3E MS=4.6  PHI  Felt with intensity II

O: 23APR2019 05:37:53  11.8N  125.2E Mw=6.4  EMSC   SAMAR, PHILIPPINES           

P: 16APR2019 115059    12.0N  124.0E 3.5-5.1 CAAAA  Luzon, Philippines         

 

An earthquake of M 6.0 also occurred today in the South Sandwich Islands continuing strong seismicity in that area this month which has included events of M 6.5 on April 5 and 9 and M 5.5 on April 16. None of these events have been reported felt in this remote area. Today's event occurred near local solar noon and may have been promoted by high tidal stresses. Forecast 115291 had expected this activity in the South Sandwich Islands around April 18-20.

 

O: 22APR2019 14:49:07  56.3S   27.5W Mw=6.0  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 18APR2019 115291    56.0S   26.0W 4.0-5.6 BAAAA  So. Sandwich Islands       

P: 20APR2019 115291    55.0S   29.0W 4.0-5.7 ABAAA  So. Sandwich Islands       

 

The strongest earthquake in the U.S. or Canada today was an M 5.5 in the Vancouver Island area of British Columbia, Canada NEIC reported it was lightly felt in Port Hardy, B.C. and in Walnut Grove and Nanaimo, B.C. and as far as Bellingham, Washington. The M 5.5 was preceded about an hour earlier by an M 4.9. These events occurred within about an hour of local solar noon and were probably promoted by high tidal stresses associated with the full moon. The last earthquake within about  150 km of today's epicenter with M>=5.5 in the Vancouver Island region occurred with M 6.5 on October 22, 2018 and prior to that an M 5.5 on March 18, 2016 more that three years ago. Forecast 115209 had expected a moderately large quake was possible in this area in mid-April. This epicenter is at 102 degrees from the M 6.8 in Sulawesi of April 12, the last major earthquake in the world and was probably promoted by concentrated energy from that source.

 

O: 22APR2019 21:44:44  50.3N  130.2W Mw=5.5  EMSC   VANCOUVER ISLAND, CANADA REGIO

O: 22APR2019 21:44:45  50.3N  130.1W mw=5.5  ANSS   Port Hardy Canada

O: 22APR2019 20:26:59  50.4N  130.0W Mw=4.9  EMSC   VANCOUVER ISLAND, CANADA REGIO

P: 16APR2019 115209    50.7N  130.5W 3.0-5.2 CAAAA  British Colombia           

 

A moderately strong earthquake of M 5.4 also rocked areas of Central Mexico today. This event in Oaxaca State was felt with intensity II-III as far as 400 km from the epicenter (NEIC) at Oaxaca, Tlaxcatancingo, Puebla, Tres Marias, Zacamulpa, Mexico City And Naucalpan, Mexico among others.  An earthquake of M 4.3 in eastern Oaxaca occurred earlier in the day. This event was reported by NEIC to have been felt with intensity IV in Xadani, Oaxaca and II-III in Huatulco, Pochutta, Oaxaca, Mexico. The M 5.4 is the strongest within about 100 km of this epicenter since an M 5.9 on February 19, 2018, an aftershock of an M 7.2 on February 16, 2018.  Forecast 115068 had expected this activity within about 100 km was likely around April 19.

 

O: 22APR2019 16:29:45  15.9N   98.8W ML=4.1  EMSC   OFFSHORE GUERRERO, MEXICO

O: 22APR2019 18:00:01  15.9N   98.8W ML=4.5  EMSC   OFFSHORE GUERRERO, MEXICO

O: 23APR2019 05:46:03  16.0N   98.7W ML=4.0  EMSC   OFFSHORE GUERRERO, MEXICO

O: 23APR2019 05:30:42  16.0N   98.7W ML=4.0  EMSC   OFFSHORE OAXACA, MEXICO

O: 22APR2019 21:49:04  16.0N   98.7W ML=4.1  EMSC   OFFSHORE GUERRERO, MEXICO

O: 22APR2019 23:22:39  16.0N   98.7W ML=4.1  EMSC   OFFSHORE GUERRERO, MEXICO

O: 22APR2019 21:46:42  16.1N   98.7W ML=4.0  EMSC   OFFSHORE GUERRERO, MEXICO

O: 22APR2019 17:56:50  16.1N   98.7W ML=4.3  EMSC   OFFSHORE GUERRERO, MEXICO

O: 23APR2019 06:32:19  16.3N   98.5W ML=4.1  EMSC   OAXACA, MEXICO

O: 22APR2019 20:15:26  16.4N   98.4W Mw=5.4  EMSC   OAXACA, MEXICO

O: 22APR2019 20:45:27  16.4N   98.5W mb=4.5  EMSC   GUERRERO, MEXICO             

P: 19APR2019 115068    17.0N   98.0W 3.5-5.3 BAAAA  Oaxaca, Mexico              

 

TIDAL STRESSES, OTHER PROMOTERS MAY BRING ENHANCED GLOBAL SEISMICITY

 

EARTHQUAKE SUMMARY FOR APRIL 21, 2019

 

The current lull in global seismicity continued today. A geomagnetic storm is on the horizon and two ocean storms show promise to become tropical cyclones. This activity is likely to combine with the full moon tides to promote enhanced seismicity as noted in previous summaries:

 

"The full moon will arrive at 11:12 UT on April 19, 2019. Longitudes which are sub-solar at this time are near 15 East and 165 West. These include areas of central and western Europe in the east and the Aleutian Islands and western Alaska in the West. Other areas which may see enhanced tidal promotion at this time are the Kermadec-Tonga arc north to Samoa. While these regions will experience maximum stress from the tidal alignment, many other areas could see enhanced seismicity in the next five days and a strong earthquake is likely in this time period." (April 19-22, 2019)

 

The strongest earthquake in the world today occurred in the Tonga/Fiji zone and was likely promoted by tidal stresses. This event of M 5.4 southeast of the Loyalty Islands was somewhat unusual. The last earthquake of M>=5.4 within about 250 km of this epicenter occurred nearly two years ago as an M 5.7 on July 8, 2017. A strong M 7.2 hit the area about 200 km to the west on August 12, 2016. Forecast 115264 had expected regional seismicity in the Loyalty Islands in mid April.

 

O: 22APR2019 04:38:03  22.1S  170.0E mb=4.7  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

O: 21APR2019 09:24:41  22.1S  174.9E Mw=5.4  EMSC   SOUTHEAST OF LOYALTY ISLANDS 

P: 16APR2019 115264    23.0S  170.0E 4.0-5.8 BAAAA  Loyalty Islands            

 

An earthquake of M 4.5 continued the activity in the Mayotte region east of Africa today. The current Mayotte series began a year ago on May 13, 2018i with an M 5.1. The last event of M>=4.5 in the area was an M 5.0 on April 5, 2019. Forecast 115248 had expected activity in the region was likely around April 22. A new tropical cyclone to the northeast of this may have helped promote today's activity as noted in this summary:

 

"A tropical cyclone may be forming in the area north of Madagascar. This system is currently located near 10S 51E with winds up to 30 kts and moving westward at 6 kts. The area of Mayotte may be active as this storm approaches." (April 21-22, 2019)

 

NEIC reported this earthquake of M 4.5 in Mayotte was felt with intensity II-III in the area(s) of Mamoudzou, Mayotte.

 

O: 22APR2019 04:27:43  12.8S   45.4E mb=4.5  EMSC   MAYOTTE REGION               

P: 18APR2019 115248    14.0S   44.0E 3.0-4.4 BBBAA  Madagascar area            

 

The strongest earthquakes in the U.S. or Canada today occurred in Central  Alaska and in Central California with M 3.4-3.5. The M 3.4 in Central Alaska

was felt lightly in the epicentral area.  It is the strongest event within about 150 km of this epicenter since an M 3.7 on January 17, 2019 and prior to that an M 3.6 on November 30, 2018. These occurred about 150 km north of today's epicenter. Forecast 115234 had expected today's activity within about 25 km of the epicenter was likely around April 19.

 

O: 22APR2019 02:04:32  62.7N  148.7W ML=3.4  EMSC   CENTRAL ALASKA               

P: 19APR2019 115234    62.8N  149.1W 3.2-4.9 BAAAA  Central Alaska              

 

The M 3.5 in Central California was felt widely in the area.  NEIC reported this earthquake of M 3.5 in Central California was felt with intensity IV in Carmel Valley,  California and II-III in the area(s) of California at Gonzales, Soledad, Paicines, Hollister, Salinas, San Juan Bautista, Greenfield.  This is the strongest earthquake within about 50 km of this epicenter in nearly half a year - since an M 3.6 and 4.1 on November 2, 2018. Events of M 3.5 hit the area on November 10, 2018, an aftershock of the November 2 event and with M 3.8 on October 5, 2018, a foreshock, the only such events in the past year. Forecast 115100 had expected today's event within about 25 km of this epicenter was likely in mid-April.

 

O: 22APR2019 05:45:09  36.6N  121.2W Ml=3.5  EMSC   CENTRAL CALIFORNIA           

P: 16APR2019 115100    36.7N  121.4W 2.5-4.4 CAAAA  Central California         

 

SWARM HITS KOMANDORSKY ISLANDS, RUSSIA

 

EARTHQUAKE SUMMARY FOR APRIL 20, 2019

 

Quiet global seismic conditions continued today. The strongest earthquake of the day was an M 5.3 in the Komandorsky Islands of Russia. It was part of a swarm in the area including two events of M 4.8. The M 5.3 is the strongest earthquake within about 200 km of this epicenter in the Komandorsky Islands since an  M 5.4 on January 3, 2019 and prior to that an M 7.3 and aftershocks of December 20, 2018. Forecast 115214 had expected this activity in the Komandorsky Islands was likely around April 14-20. None of these events were reported felt in this remote area.

 

O: 21APR2019 01:38:55  54.8N  164.7E mb=4.0  EMSC   KOMANDORSKIYE OSTROVA REGION 

O: 21APR2019 00:50:27  54.8N  164.7E mb=4.2  EMSC   KOMANDORSKIYE OSTROVA REGION 

O: 20APR2019 22:12:16  54.8N  164.7E mb=4.8  EMSC   KOMANDORSKIYE OSTROVA REGION 

O: 20APR2019 22:34:39  54.9N  164.7E Mw=5.3  EMSC   KOMANDORSKIYE OSTROVA REGION 

O: 20APR2019 22:46:36  54.9N  164.7E mb=4.8  EMSC   KOMANDORSKIYE OSTROVA REGION 

P: 14APR2019 115214    55.0N  165.0E 4.0-5.9 CAAAA  Komandorsky Isl            

P: 20APR2019 115214    55.0N  169.0E 4.0-5.9 AACAA  Near Islands               

 

The strongest earthquake in the U.S., Canada or vicinity today was an M 5.1 in the western Andreanof Islands, Aleutians, Alaska. It was not reported felt in this remote epicentral area. This is the strongest earthquake reported within about 150 km of this epicenter since an M 5.9 on January 5, 2019 and prior to that an M 6.3 on August 23, 2018. Forecast 115206 had expected today's event within this area was likely around April 19.

 

 

O: 20APR2019 20:49:23  50.4N  179.0W mb=3.7  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

O: 21APR2019 06:31:38  51.6N  178.3W mb=5.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

O: 21APR2019 06:31:38  51.4N  178.2W mb=5.2  ANSS   ANDREANOF ISLANDS, ALEUTIAN IS

P: 19APR2019 115206    51.9N  179.8W 3.5-4.9 AAAAA  Andreanoff Isls, Aleutians 

 

An M 4.5 also occurred today in Northern Baja, Mexico. NEIC reported it was felt with intensity II-III in Northern Baja California at San Felipe, Ensenada, Jacumba, Primo Tapia and in portions of Southern California with lesser intensity. This is the strongest earthquake within about 100 km of this epicenter in Baja Mexico since an M 4.6 more than five years ago on December 20, 2013. An M 4.8 about  150 km northeast of this occurred on November 19, 2018.

Forecast 115133 had expected activity up to M 5.5 in this region in mid-April.

 

O: 20APR2019 14:41:50  31.2N  115.8W Mw=4.5  EMSC   BAJA CALIFORNIA, MEXICO      

O: 20APR2019 07:28:16  32.5N  115.6W Ml=2.1  EMSC   BAJA CALIFORNIA, MEXICO      

P: 13APR2019 115133    32.9N  115.6W 2.5-4.4 CAAAA  So. California             

 

RELAXED SEISMICITY; QUIET DAY

 

EARTHQUAKE SUMMARY FOR APRIL 19, 2019

 

Global seismicity was quiet today. There were no significant earthquakes recorded in the Western Hemisphere and only a few of M 5.0-5.2, mostly in the Solomon Islands and southwest Pacific in the Eastern Hemisphere. While the full moon arrived today, with the lack of ocean storm and solar and geomagnetic conditions at very quiet levels, the tidal stresses may not be sufficient to help promote strong seismicity at this time. The tidal forecast had read:

 

 

"The full moon will arrive at 11:12 UT on April 19, 2019. Longitudes which are sub-solar at this time are near 15 East and 165 West. These include areas of central and western Europe in the east and the Aleutian Islands and western Alaska in the West. Other areas which may see enhanced tidal promotion at this time are the Kermadec-Tonga arc north to Samoa. While these regions will experience maximum stress from the tidal alignment, many other areas could see enhanced seismicity in the next five days and a strong earthquake is likely in this time period." (April 19-21, 2019)

 

The strongest earthquake of the day was an M 5.2-5.3 in Mindanao, Philippines. It was not reported felt in the epicentral area of Mindanao. Forecast 115022 had expected this event within about 150 km of the epicenter was likely around April 19.

 

O: 19APR2019 07:08:19   5.5N  125.7E ML=4.2  EMSC   MINDANAO, PHILIPPINES        

O: 19APR2019 07:29:58   5.5N  126.8E Mw=5.2  EMSC   MINDANAO, PHILIPPINES        

O: 19APR2019 07:29:53   5.2N  127.0E MS=5.3  PHI  Not reported felt.             

P: 19APR2019 115022     4.0N  126.0E 4.0-5.6 ABAAA  Mindanao, Philippines      

 

O: 20APR2019 03:48:21  10.3S  161.2E mb=5.0  EMSC   SOLOMON ISLANDS              

P: 21APR2019 115249    10.0S  162.0E 4.0-5.4 AAAAA  No. of Santa Cruz Islands  

 

O: 19APR2019 23:02:53  18.4S  177.7W Mw=5.0  EMSC   FIJI REGION                  

P: 18APR2019 115257    19.0S  175.0W 4.0-5.8 AACAA  Tonga Islands              

 

O: 20APR2019 06:52:10  25.5S  179.6E mb=4.9  EMSC   SOUTH OF FIJI ISLANDS        

P: 12APR2019 115271    23.0S  179.0E 4.0-5.7 CCAAA  Tonga/Fiji                 

 

STRONG QUAKE SOUTH OF AUSTRALIA

 

EARTHQUAKE SUMMARY FOR APRIL 18, 2019

 

The strongest earthquake in the world today was an M 6.5 in the Western Antarctic-Indian Ridge south of Australia. It was not reported felt in this remote area. This is the largest earthquake on the Western Indian-Antarctic Ridge within about 300 km of this epicenter since an M 6.6 on June 11, 2000, the only other such event in the area in at least 30 years. Forecast 115288 had expected activity on the Ridge was likely around April 21.

 

O: 18APR2019 14:46:01  51.1S  139.5E Mw=6.5  EMSC   WESTERN INDIAN-ANTARCTIC RIDGE

P: 21APR2019 115288    49.0S  122.0E 4.0-5.6 BBCAA  So. of Australia           

 

The largest earthquake in the U.S. or Canada today was an M 3.4 in Hawaii. NEIC reported this earthquake of M 3.4 in Hawaii was felt with intensity II-III in the area(s) of Kailua Kona, Waikoloa, Kamuela, Holualoa, Dealakekua, Honaunau, Captain Cook, Naalehu and Kailua, Hawaii. This is the strongest tectonic earthquake in Hawaii since an M 5.2-5.3 occurred several days ago on April 14, 2019 and prior to that an M 3.4 on March 31, 2019. It may have been promoted by tidal effects associated with the full moon as it occurred near local solar noon but is probably an aftershock of the April 14 event as it occurred at the same epicenter. Forecast 115056 had expected this activity was likely around April 15. The tidal forecast had noted maximum tides near the longitude of Hawaii at this time as:

 

"The full moon will arrive at 11:12 UT on April 19, 2019. Longitudes which are sub-solar at this time are near 15 East and 165 West. These include areas of central and western Europe in the east and the Aleutian Islands and western Alaska in the West. Other areas which may see enhanced tidal promotion at this time are the Kermadec-Tonga arc north to Samoa. While these regions will experience maximum stress from the tidal alignment, many other areas could see enhanced seismicity in the next five days and a strong earthquake is likely in this time period." (April 19-21, 2019)

 

O: 19APR2019 00:27:58  19.8N  155.8W ML=3.4  EMSC   ISLAND OF HAWAII, HAWAII     

P: 15APR2019 115056    19.2N  155.2W 3.0-4.4 BAAAA  Hawaii                     

 

Unusual earthquakes which may have been promoted by the full moon today included

an M 4.3 in South Korea; an M 4.5 in the DR Congo and an M 3.7 in Sarawak, Indonesia. The events in the Congo and  in South Korea occurred  near local solar noon, a time when tidal stresses with full moon maximize. Forecast 115033 had expected a moderate quake in the Congo region within about  200 km of today's epicenter in mid-April.

 

O: 18APR2019 08:18:27   0.8S   27.5E mb=4.5  EMSC   DEMOCRATIC REPUBLIC OF THE CON

P: 14APR2019 115033     2.0S   29.0E 3.0-4.9 BBBAA  Lake Victoria area         

 

O: 19APR2019 02:16:43  37.9N  129.5E ML=4.3  EMSC   SOUTH KOREA                  

P: 18APR2019 115115    32.0N  132.0E 3.5-4.9 ACBAA  Kyushu, Japan area         

 

O: 18APR2019 20:48:38   1.9N  111.5E ML=3.8  EMSC   SARAWAK, MALAYSIA            

 

STRONG QUAKE RATTLES TAIWAN

 

EARTHQUAKE SUMMARY FOR APRIL 17, 2019

 

A strong earthquake of M 6.1 shook most of Taiwan today. High-rise buildings in Taipei swayed during the quake. NEIC reported maximum intensit VI in Hualien, Taipei, and Miaoli and IV in Ilan, Taichung with lesser shaking in Hsinchu Counties, Taiwan. CWB reported this earthquake was felt with intensity VII in Hualien; V in Nantou, Yilan, Taichung, Taipei; IV in Taoyuan, Hsnichu, Miaoli, Changhua; III in Chiayi, Yunlin, Taitung; II in Kaohsiung, Tainan and Penghu and I in Pingtung Counties, Taiwan. The M 4.1 aftershock was felt with intensity V in Hualien; III in Nantou and II in Taichung and Yilan Counties, Taiwan. More than a dozen people were reported injured in this earthquake which stopped public transportation. Two hikers were injured by rock slides and at least 15 were injured by falling debris in the area of Taipei. The China Earthquake Networks Center gave the event M 6.7. Schools were closed and some roads were shut down for inspection. At least two building were evacuated due to structural damage. Today's M 6.1 occurred within about an hour of local solar noon when Taiwan was near the sub-solar point on the earth (the point where the sun is directly overhead at local solar noon). It was probably promoted by strong tidal stresses associated with the full moon which occurs tomorrow. These maximize near this hour. A moderate foreshock hit the same epicenter on April 9, 2019 following a series of moderate regional events in early April.  Today's event of M 6.1 is the strongest in Taiwan since an M 6.4 on February 6, 2018 – that followed an M 6.1 on February 4, 2018, earthquakes which occurred about 25 km north of today's epicenter. These were the largest in Taiwan since February 5, 2016 when an M 6.4 hit the area southwest of today's activity. Forecast 115091 had expected today's event within about 50 km of the epicenter was likely around April 18.

 

O: 18APR2019 05:17:26  24.1N  121.5E ML=4.1  EMSC   TAIWAN                       

O: 18APR2019 05:01:07  24.1N  121.5E ML=6.1  TAI    Hualien, Taiwan              

O: 18APR2019 05:01:06  24.0N  121.7E mw=6.1  ANSS   E of Hualian Taiwan

O: 18APR2019 05:17:27  24.1N  121.5E ML=4.1  TAI    Hualien, Taiwan              

O: 18APR2019 05:01:06  24.1N  121.5E Mw=6.1  EMSC   TAIWAN                       

P: 18APR2019 115091    24.0N  121.0E 4.0-5.4 AAAAA  Taiwan                     

 

An earthquake of M 5.6 in Central Chile preceded the M 6.1 in Taiwan by about an hour. NEIC reported it was felt with intensity V in Coquimbo; IV in La Serena and Vicuna and II-III in Salamanca, Villa Alemana, Lampa and Santiago, Chile. CSN reported this earthquake was felt with intensity VI in  Coquimbo at La Higuera, La Serena; V in Monte Patria, Ovalle, Paiguano, Vicuna; IV in Punitaqui, Salamanca; Canela, Combarbala, Coquimbo; III in Illapel and Andacollo; Atacama with V in Freirina, Huasco and Vallenar IV in Alto del Carmen, Copiapo and Tierra Amarilla and III in Caldera, Chile. This event occurred within less than an hour of local solar midnight and may have been promoted by stresses associated with the full moon alignment which maximizes on April 19. Two events of M>=5.6 have occurred within about 200  km of today's epicenter in the past year - an M 5.7 on March 7, 2019 and an M 6.7 on January 20, 2019. Forecast 115262 had expected today's earthquake was likely within about 50 km of this epicenter around April 19.

 

O: 18APR2019 04:06:33  29.3S   71.6W Mw=5.6  EMSC   OFFSHORE COQUIMBO, CHILE     

O: 18APR2019 04:06     29.4S   71.6W mb=5.6  GUC    Coquimbo at La Higuera, La Ser

P: 19APR2019 115262    29.0S   72.0W 4.0-5.5 AAAAA  Coast Central Chile        

 

The strongest earthquake in the U.S. or Canada today was an M 4.9 in the Fox Islands, Aleutians, Alaska. As it occurred within a few degrees longitude of the maximum tidal stresses  associated with the upcoming full moon it may have been promoted by that alignment as noted in this summary:

 

"The full moon will arrive at 11:12 UT on April 19, 2019. Longitudes which are sub-solar at this time are near 15 East and 165 West. These include areas of central and western Europe in the east and the Aleutian Islands and western Alaska in the West. Other areas which may see enhanced tidal promotion at this time are the Kermadec-Tonga arc north to Samoa. While these regions will experience maximum stress from the tidal alignment, many other areas could see enhanced seismicity in the next five days and a strong earthquake is likely in this time period." (April 17-18, 2019)

 

Two earthquakes of M>=4.9 have occurred within the Fox Islands within about 150 km of this epicenter in the past 1.5 years - an M 5.1 on January 28, 2018 more than a year ago and an M 4.9 on December 10, 2017. The last such event of significantly larger magnitude was an M 5.3 on August 9, 2017. Forecast 116212 had expected a moderate earthquake in this area around April 17.

 

O: 18APR2019 02:44:39  52.3N  168.5W mb=4.9  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 17APR2019 115212    53.6N  166.1W 3.5-5.1 ABBAA  Fox Islands, Aleutians     

 

MODERATE QUAKES HIT SOUTHERN OCEAN AREAS

 

EARTHQUAKE SUMMARY FOR APRIL 16, 2019

 

A series of moderate earthquakes of M 5.5-5.8 hit across the Southern Oceans today. The strongest of these were a series in the central Kermadec Islands of New Zealand (M 5.5, 5.7, 5.8) An M 5.7 also occurred on the opposite side of the world in the southern Atlantic near Tristan da Cunha (M 5.7) and to the south of this in the South Sandwich Islands (M 5.5).

 

The strongest of the activity in the southern oceans today was a series of moderately large events in the Kermadec Islands of northern New Zealand of M 5.0, 5.5, 5.7 and 5.8. This is a sparsely populated region and earthquakes are seldom reported felt by the local population. A series of moderately large to large quakes has hit the area in recent week, the largest of which was an M 6.4 on March  6, 2019. Forecast 115282 had expected today's activity was likely around April 18.

 

O: 16APR2019 09:39:37  30.9S  178.8W Mw=5.7  EMSC   KERMADEC ISLANDS, NEW ZEALAND

O: 16APR2019 09:22:32  31.1S  179.0W Mw=5.8  EMSC   KERMADEC ISLANDS REGION      

P: 18APR2019 115282    32.0S  179.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

 

O: 17APR2019 05:03:42  31.8S  179.9E mb=5.0  EMSC   KERMADEC ISLANDS REGION      

O: 16APR2019 16:01:15  32.4S  179.4W Mw=5.5  EMSC   SOUTH OF KERMADEC ISLANDS    

P: 18APR2019 115282    32.0S  179.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

 

The earthquake in Tristan da Cunha area of the South Atlantic was also not felt in this remote area. It is the strongest earthquake within about 300 km of this epicenter since an M 5.7 on July 2, 2015. That event was an aftershock of the strongest quake in the area in at least 30 years - an M 7.0 on June 17, 2015.

 

O: 16APR2019 07:30:39  35.3S   15.5W mb=5.7  EMSC   TRISTAN DA CUNHA REGION      

 

The M 5.5 in the eastern South Sandwich Islands continued strong seismicity in that area during the current month. This was not felt in this remote area.  It is the strongest earthquake within about 100 km of this epicenter since an M 5.7 on December 10, 2015. An M 6.5 hit about 100 km west of this on April 9, 2019. Today's event is probably a regional aftershock of the M 6.5. Forecast 115293 had expected activity in  this area was likely with magnitude up to M 5.5 around April 18.

 

O: 16APR2019 16:59:16  58.7S   23.7W mb=5.5  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 18APR2019 115293    61.0S   26.0W 4.0-5.5 ACBAA  Southern  Ocean            

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the western Andreanof Islands. It was not reported felt in this remote area. The last earthquake with M>=4.2 in the western Andreanof Islands occurred on March 22, 2019 with M 4.8. Ten such quakes have occurred in this area during 2019. Forecast 115206 had expected today's event within about 50 km of this epicenter was likely around April 19.

 

O: 16APR2019 21:31:00  50.9N  179.4W mb=4.2  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 19APR2019 115206    50.5N  179.8W 3.5-5.3 BAAAA  Andreanoff Isls, Aleutians 

 

NORTHERN CALIFORNIA ACTIVE

 

EARTHQUAKE SUMMARY FOR APRIL 15, 2019

 

A pair of moderate earthquakes occurred in northern California today - an M 4.1 in the Geysers area north of San Francisco and an M 4.2 and foreshocks in the Bishop/Mammoth Lakes area near the central Nevada border. This summary has previously argued that seismicity in California peaks in mid-April to early May and this appears to confirm that analysis.

 

An M 4.2 was widely felt in the Mammoth Lakes region of central California today. NEIC reported intensity II-III in Bishop, Mammoth Lakes, Shaver Lake, Auberry, Squaw Valley, Yosemite and El Portal, California. An M 3.4 foreshock two minutes earlier was felt with intensity III in Bishop. Smaller foreshocks earlier in the day were also felt lightly in Bishop, California. The last earthquake in the Bishop/Mammoth Lakes region of M>=4.2 occurred on December 28, 2016 when an M 5.7 about 100 km northwest of today's event was followed by a series of aftershocks of M 5.6 and 5.7. The last such event in the Bishop area occurred more than three years ato on February 16, 2016.  Forecasts 115095 and 115098 had expected this activity was likely around April 13.

 

O: 15APR2019 18:24:08  37.4N  118.5W Md=2.0  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 18:07:26  37.4N  118.5W Md=2.2  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 19:04:36  37.4N  118.5W Md=2.2  EMSC   CENTRAL CALIFORNIA

O: 16APR2019 01:09:44  37.4N  118.5W Md=2.7  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 14:19:16  37.4N  118.5W Md=2.9  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 22:39:17  37.4N  118.5W Mh=2.1  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 15:58:47  37.4N  118.5W Mw=3.4  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 12:20:25  37.4N  118.5W ml=2.2  EMSC   CENTRAL CALIFORNIA

O: 15APR2019 17:55:58  37.4N  118.5W ML=4.2  EMSC   CENTRAL CALIFORNIA           

P: 13APR2019 115095    37.3N  119.4W 2.5-4.6 AAAAA  California/Nevada area     

P: 13APR2019 115098    38.4N  118.2W 2.5-4.4 AAAAA  California/Nevada area     

 

The last event in the Geysers area of northern California with M>=4.1 was an M 4.2 on May 10, 2018. The last of larger magnitude was an M 5.0 on December 14, 2016. Forecast 115102 had expected this event within about 15 km of the epicenter was likely around April 13.

 

O: 15APR2019 12:10:26  38.8N  122.8W Md=2.0  EMSC   NORTHERN CALIFORNIA

O: 15APR2019 13:06:39  38.8N  122.8W Md=2.0  EMSC   NORTHERN CALIFORNIA

O: 15APR2019 11:56:18  38.8N  122.8W Md=2.2  EMSC   NORTHERN CALIFORNIA

O: 15APR2019 12:05:26  38.8N  122.8W Md=2.2  EMSC   NORTHERN CALIFORNIA

O: 15APR2019 15:18:47  38.8N  122.8W Md=2.2  EMSC   NORTHERN CALIFORNIA

O: 16APR2019 01:23:14  38.8N  122.8W Md=2.2  EMSC   NORTHERN CALIFORNIA

O: 15APR2019 11:54:03  38.8N  122.8W mw=4.1  ANSS   NW of The Geysers

O: 15APR2019 11:54:03  38.8N  122.8W Mw=4.1  EMSC   NORTHERN CALIFORNIA          

P: 13APR2019 115102    38.7N  122.7W 2.5-4.6 AAAAA  Central California         

 

 

The strongest earthquake in the U.S. or Canada today was an M 4.7 in Northern Alaska. NEIC reported it was felt with intensity II-III in Alaska at Huslia and Hughes. Moderate earthquakes in this area began on February 10, 2019 with M 4.8. Aftershocks of M 5.2 later occurred on March 6 and March 26, 2019. Forecast 115227 had expected this area would be active in mid-April.

 

O: 16APR2019 05:07:47  66.3N  157.2W ML=4.7  EMSC   NORTHERN ALASKA

O: 16APR2019 06:22:15  66.3N  157.5W ml=3.0  EMSC   NORTHERN ALASKA

O: 16APR2019 05:35:46  66.3N  157.5W ml=3.1  EMSC   NORTHERN ALASKA

O: 16APR2019 05:18:10  66.3N  157.0W ml=3.1  EMSC   NORTHERN ALASKA              

P: 14APR2019 115227    65.1N  154.4W 3.2-5.1 ABBAA  Northern Alaska            

 

MODERATE EVENTS IN NORTHERN PHIIPPINES; RAT ISLANDS, ALEUTIANS

 

EARTHQUAKE SUMMARY FOR APRIL 14, 2019

 

It was a relatively quiet day in global seismicity. The strongest earthquakes were of M 5.2-5.3 and occurred in the northern Philippines and in the Rat Islands, Aleutians, Alaska.  PHIVOLCS reported the earthquake in the northern Philippines was felt with intensity IV in Calayan, Cagayan, III in Pasuquin, Pagudpud, Bangui, Adams and Laoag, Ilocos Norte and II in Sinait, Ilocos Sur; Bacarra, Currimao, Badoc and Burgos, Ilocos, Norte, Philippines

An event of M 5.6 hit about 100 km southwest of today's epicenter on March 2, 2019 and an M 5.5 occurred at today's epicenter on January 24, 2019. Today's event is the strongest aftershock to date of the January event. Forecasts 115060 and 115090 had expected today's activity was likly in mid-April.

 

O: 15APR2019 01:33:00  19.2N  121.1E Mw=5.1  EMSC   BABUYAN ISL REGION, PHILIPPINE

O: 15APR2019 01:32:59  19.2N  120.9E MS=5.2  PHI  Felt with intensity IV

P: 13APR2019 115060    18.0N  120.0E 3.5-4.9 ABAAA  Luzon, Philippines         

P: 20APR2019 115090    20.0N  121.0E 4.0-5.4 BAAAA  Taiwan                     

 

The strongest earthquake in the U.S., Canada or the world today was an M 5.3 in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote area. The last earthquake within about 200 km of this epicenter in the Rat Islands with M>=5.3 occurred on April 2, 2019 with M 6.4 and prior to that an M 6.6 on October 8, 2017. Today's event is probably an aftershock of the April 2 M 6.4.   Forecast 114938 had expected today's event within about 10 km of the epicenter was likely around April 11. This epicenter is at 101 degrees from the M 7.5 in Ecuador of February 22, 2019 and may have been promoted by concentrated energy from that event.

 

O: 14APR2019 15:30:36  52.0N  178.1E Mw=5.3  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 11APR2019 114938    52.0N  178.0E 4.0-6.0 BAAAA  Rat Islands                

 

DERATE EARTHQUAKE SHAKES HAWAII

 

EARTHQUAKE SUMMARY FOR APRIL 13, 2019

 

The strongest earthquake in the U.S. or Canada today was an M 5.3 in the Island of Hawaii. NEIC reported it was felt with moderate intensity V in Hawaii at Kailua Kona, Holualoa, Waikoloa, Kealakekua, Captain Cook; IV in Kamuela, Paauilo, Honokaa, Kapaau, and lesser intensity within about 300 km of the epicenter. Several aftershocks were also reported felt with light to moderate intensity. The last tectonic (as opposed to volcanic) earthquake in Hawaii of M>=5.3 within about 150 km of this epicenter occurred a month ago as an M 5.5 on March 13, 2019 and prior to that an M 6.1 and M 6.7 on October 15, 2006. Forecast 115056 had expected a moderate earthquake in the area around April 15.

 

O: 14APR2019 03:09:00  19.7N  156.0W Mw=5.1  EMSC   ISLAND OF HAWAII, HAWAII     

O: 14APR2019 03:09:00  19.7N  155.8W Mw=5.3  ANSS   ISLAND OF HAWAII, HAWAII     

P: 15APR2019 115056    19.2N  155.2W 3.0-4.4 AAAAA  Hawaii                     

 

A moderate M 4.1 also occurred today in central Utah. This is the strongest earthquake in the area within about 100 km of the epicenter since an M 4.3 on January 15, 2016 and prior to that an M 4.1 on July 4, 2015. An M 4.0 occurred about 30 km to the east of this on February 20, 2019, the latest moderate event in the area. Forecast 115155 had expected today's evnet was likely within about 25 km of this epicenter around April 16.

 

O: 14APR2019 04:09:17  38.8N  112.8W ML=2.9  EMSC   UTAH                         

O: 14APR2019 03:59:54  38.8N  112.8W ML=4.0  EMSC   UTAH                         

O: 14APR2019 03:59:54  38.8N  112.8W ML=4.1  ANSS   UTAH                         

P: 16APR2019 115155    38.6N  112.7W 2.0-4.3 AAAAA  Utah area                  

 

The most active area in the world today was the Ryukyu Islands, Japan where a swarm of moderate events continued today. The largest of these were M 5.0, 5.0 and 5.2. The last event of M>=5.2 within about 150 km of this activity occurred as an M 5.5 on April 8, 2019.  NEIC reported today's earthquake of M 5.2 in the Ryukyu Islands, Japan was felt with intensity II-III in the area(s) of Okinawa at Ginowan, Okinawa and Yomitan, Japan.  Forecast 114829 had expected this activity in this area in early April. A foreshock of M 5.5 on April 8, 2019 was the only such event in the region since September 22, 2018 (M 5.4).

 

O: 13APR2019 08:59:34  26.1N  129.5E mb=4.6  EMSC   RYUKYU ISLANDS, JAPAN        

O: 14APR2019 05:11:58  26.2N  129.4E mb=4.8  EMSC   RYUKYU ISLANDS, JAPAN        

O: 13APR2019 07:08:14  26.2N  129.5E Mw=4.9  EMSC   RYUKYU ISLANDS, JAPAN        

O: 13APR2019 07:11:00  26.2N  129.5E Mw=5.0  EMSC   RYUKYU ISLANDS, JAPAN        

O: 13APR2019 15:07:01  26.2N  129.5E mb=5.0  EMSC   RYUKYU ISLANDS, JAPAN         

O: 14APR2019 05:40:26  26.3N  129.4E mb=4.8  EMSC   RYUKYU ISLANDS, JAPAN        

O: 13APR2019 07:14:29  26.3N  129.5E Mw=4.9  EMSC   RYUKYU ISLANDS, JAPAN        

O: 14APR2019 01:53:10  26.3N  129.5E Mw=5.2  EMSC   RYUKYU ISLANDS, JAPAN        

O: 13APR2019 08:17:56  26.3N  129.5E mb=4.6  EMSC   RYUKYU ISLANDS, JAPAN        

P:  7APR2019 114829    26.0N  128.0E 4.0-5.4 CAAAA  Ryukyu Islands             

 

 

STRONG QUAKE SHAKES SULAWESI, INDONESIA

 

EARTHQUAKE SUMMARY FOR APRIL 12, 2019

 

A strong M 6.8 earthquake hit the region of Sulawesi, Indonesia north of the Banda Sea. NEIC reported maximum intensity V in Sulawesi at Luwuk; IV in Palu and Makasar and II-III in Rantepao and Manado, Sulawesi. This was accompanied by strong regional seismicity the Banda Sea, Ceram, and Sulawesi. The M 6.8 is the strongest earthquake in the world since an M 7.0 on March 1, 2019 in Southern Peru. This epicenter in Sulawesi is north of the Banda Sea and is probably related to the passage of Tropical Cyclone Wallace directly to the south today. When an M 6.3-6.5 hit the Banda Sea of April 7, this summary noted:

 

"The earthquake of M 6.3 in the Banda Sea was not reported felt in that area. As noted, it occurred near the eye of Tropical Cyclone Wallace and was probably promoted from that source as noted in previous issues:

 

"A tropical cyclone may be forming in the Banda Sea, Indonesia. This system is currently located at 9S 130E with winds up to 33 kts and moving to the WSW at 9 kts. Some enhanced seismicity may accompany this storm in the Banda Sea area in the next several days." (April 3-4, 2019)

 

and

 

"Tropical cyclone Wallace continued in the Banda Sea, Indonesia with winds up to 55 kts. This system is currently moving to the WSW at 6 kts. Some enhanced seismicity may accompany this storm in the Banda Sea area in the next several days. This may include a strong earthquake." (April 5-6, 2019)

" (April 7, 2019)

 

and

 

"Tropical cyclone Wallace continued in the Banda Sea, Indonesia with winds up to 45 kts. Some enhanced seismicity may accompany this storm in the antipodal area of the eastern Caribbean in the Leeward Islands north to the Virgin Islands and Puerto Rico to the Dominican Republic. The current antipode is at 17N 67W in the Dominican Republic. Regional activity in the Banda Sea and Flores may also continue." (April 10-11, 2019)

 

Local authorities reported some minor damage from the quake. A tsunami warning was issued but later withdrawn when no waves were observed. Local residents took to the hills and returned when the warning was rescinded. The last earthquake within about 300 km of today's epicenter occurred as an M 7.6 on May 4, 2000. The only other such event in the past 30 years was an M 7.7 on November 29, 1998. An M 7.4-7.5 event also occurred about 350 km southeast of today's epicenter on October 19, 2001. Forecasts 114783, 115014 and 115045 had expected strong seismicity in this are was likely in mid-April within about 100 km of today's activity. The antipode near 2N 57W is in northeastern South America and is not a seismic area. No antipodal triggering is expected in this case but some seismic enhancement may occur in the Trinidad and Tobago area and to the east in the North Atlantic.

 

O: 13APR2019 02:29:49   1.7S  122.7E mb=4.2  EMSC   SULAWESI, INDONESIA

O: 12APR2019 20:25:55   1.8S  122.5E ML=4.2  EMSC   SULAWESI, INDONESIA

O: 12APR2019 18:35:52   1.8S  122.6E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 13:10:09   1.8S  122.6E ML=4.5  EMSC   SULAWESI, INDONESIA

O: 12APR2019 20:15:09   1.8S  122.6E Mw=4.8  EMSC   SULAWESI, INDONESIA

O: 12APR2019 11:40:48   1.8S  122.6E Mw=6.8  EMSC   SULAWESI, INDONESIA

O: 12APR2019 18:23:18   1.8S  122.6E mb=4.4  EMSC   SULAWESI, INDONESIA

O: 13APR2019 05:26:17   1.8S  122.6E mb=4.8  EMSC   SULAWESI, INDONESIA

O: 12APR2019 22:39:31   1.8S  122.7E mb=4.3  EMSC   SULAWESI, INDONESIA

O: 12APR2019 12:12:12   1.8S  122.7E mb=5.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 15:57:06   1.9S  122.4E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 17:03:29   1.9S  122.5E ML=4.0  EMSC   SULAWESI, INDONESIA

O: 12APR2019 23:37:28   1.9S  122.6E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 13:31:36   1.9S  122.6E ML=4.4  EMSC   SULAWESI, INDONESIA

O: 13APR2019 04:23:28   1.9S  122.6E mb=4.5  EMSC   SULAWESI, INDONESIA

O: 12APR2019 15:08:29   1.9S  122.6E mb=4.6  EMSC   SULAWESI, INDONESIA

O: 12APR2019 22:59:29   1.9S  122.6E mb=4.8  EMSC   SULAWESI, INDONESIA

O: 12APR2019 12:33:03   2.0S  122.0E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 22:29:44   2.0S  122.5E ML=4.0  EMSC   SULAWESI, INDONESIA

O: 12APR2019 15:23:58   2.0S  122.5E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 19:01:56   2.0S  122.5E ML=4.4  EMSC   SULAWESI, INDONESIA

O: 12APR2019 12:14:58   2.0S  122.5E ML=4.8  EMSC   SULAWESI, INDONESIA

O: 12APR2019 12:03:54   2.0S  122.5E mb=4.7  EMSC   SULAWESI, INDONESIA

O: 13APR2019 04:44:24   2.0S  122.6E ML=4.0  EMSC   SULAWESI, INDONESIA

O: 12APR2019 15:02:57   2.0S  122.6E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 13:00:17   2.0S  122.6E ML=4.4  EMSC   SULAWESI, INDONESIA

O: 12APR2019 13:23:41   2.0S  122.6E ML=4.5  EMSC   SULAWESI, INDONESIA

O: 13APR2019 00:22:21   2.0S  122.8E ML=4.6  EMSC   SULAWESI, INDONESIA

O: 12APR2019 22:49:03   2.1S  122.5E ML=4.4  EMSC   SULAWESI, INDONESIA

O: 12APR2019 17:30:23   2.1S  122.6E ML=4.0  EMSC   SULAWESI, INDONESIA

O: 12APR2019 14:26:49   2.1S  122.6E ML=4.2  EMSC   SULAWESI, INDONESIA

O: 12APR2019 15:59:53   2.1S  122.6E ML=4.7  EMSC   SULAWESI, INDONESIA

O: 12APR2019 15:37:03   2.1S  123.2E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 13:29:40   2.2S  122.1E ML=4.1  EMSC   SULAWESI, INDONESIA

O: 12APR2019 11:40:49   1.9S  122.6E mw=6.8  ANSS   SSW of Luwuk Indonesia       

P: 11APR2019 114783     4.0S  123.0E 4.0-5.4 ACAAA  Sulawesi area              

P: 12APR2019 115014     0.0N  122.0E 4.0-5.4 ABAAA  Celebes Sea                

P: 16APR2019 115045     1.0S  123.0E 4.0-5.7 BAAAA  Sulawesi area              

 

An M 5.8 was felt in the region of Samoa today. NEIC reported it was felt with maximum intensity V in Samoa at Siusega, NW Upolu; Apia, American Samoa and Aua, Samoa. The last earthquake within about 200 km of this epicenter in Samoa with M>=5.8  occurred on November 20, 2017 with M 6.0.   Forecast 114976 had expected today's epicenter would be active within about 50  km around April 11.

 

O: 12APR2019 12:23:03  15.4S  172.8W mb=5.8  EMSC   SAMOA ISLANDS REGION         

P: 11APR2019 114976    16.0S  173.0W 4.0-5.6 AAAAA  Tonga Islands              

 

An M 5.9 also occurred northwest of Samoa in the region of New Britain. This is the second such event in this region in the past two days. A slightly smaller M 5.6 occurred on April 11 near the same epicenter. The previous issue of this summary reported on this event as:

 

 

"The strongest earthquake in the world today as an M 5.6 in the region of New Britain, Papua New Guinea. New Britain is an active seismic area and the last earthquake in the region within about 200 km of today's event with M>=5.6 occurred on March 11, 2019 with M 5.8." (April 11-12, 2019)

 

The last event of M>5.9 in this area was an M 6.0 on July 19, 2018 and prior to that an M 6.0 on December 1, 2017.

 

O: 12APR2019 14:51:32   6.4S  148.6E Mw=5.9  EMSC   NEW BRITAIN REGION, P.N.G.   

P:  2APR2019 114774     6.0S  149.0E 4.0-5.5 CAAAA  New Ireland                

P: 13APR2019 115036     7.0S  151.0E 4.0-5.6 AABAA  New Ireland                

 

 

An earthquake of M 2.9 in the valleys west of Los Angeles preceded the M 6.8 in Sulawesi by 11 minutes, 17 seconds. While it is unlikely that one could have helped promote the other (p- waves would have taken about 15 minutes to traverse this 155 degrees distance), both may have been promoted by an external effect such as a geomagnetic disturbance.  NEIC reported this earthquake of M 2.9 in Greater Los Angeles, California was felt with intensity II-III in the area(s) of Los Angeles, Beverly Hills, Glendale, Burbank, Mission Hills and in general within about 50 km of the epicenter.  The last earthquake with M>=2.9 within about 50 km of today's epicenter was an M 2.9 on March 22, 2019. Only one other such event has occurred in the area in the past half year - an M 3.1 on February 26, 2019. Forecasts 115136 and 115137 had expected today's evnet within about 25 km was likely around April 13.

 

O: 12APR2019 11:29:31  34.1N  118.4W Ml=2.9  EMSC   GREATER LOS ANGELES AREA, CALI

P: 13APR2019 115136    33.6N  118.5W 2.5-4.4 AAAAA  So. California             

P: 13APR2019 115137    34.0N  118.7W 2.5-4.5 AAAAA  So. California             

 

The strongest earthquake in the U.S. or Canada today was an M 4.6 off the coast of Northern California. NEIC reported it was felt with light intensity along the coast at Eureka, California. This continues activation of this region off the coast of Northern California which began in late March and has included an M 5.5 on March 24, 2019. At M 4.6  today's event is the strongest in the area within about 150 km of the epicenter since an M 6.0 and 5.8 on January 25, 2018. Forecast 115188 and 115190 had expected this activity within about 15 km of the epicenter was likely in mid-April.

 

O: 12APR2019 14:06:26  40.4N  127.0W mb=4.6  EMSC   OFF COAST OF NORTHERN CALIFORN

P: 14APR2019 115190    40.9N  126.3W 2.5-4.4 AAAAA  Off Coast of No. Calif     

P: 18APR2019 115188    40.4N  127.2W 2.5-4.6 CAAAA  Off Coast of No. Calif     

 

 

 

 

MODERATE NEW BRITAIN QUAKE; ALABAMA/FLORIDA BORDER REMAINS ACTIVE

 

EARTHQUAKE SUMMARY FOR APRIL 11, 2019

 

The strongest earthquake in the world today as an M 5.6 in the region of New Britain, Papua New Guinea. New Britain is an active seismic area and the last earthquake in the region within about 200 km of today's event with M>=5.6 occurred on March 11, 2019 with M 5.8. An earthquake in Alabama of M 3.1 also began a series in that area on March 11, 2019. Forecast 115036 expected today's event was likely to the east of today's epicenter around April 13.

 

O: 11APR2019 21:31:50   6.5S  148.7E Mw=5.6  EMSC   NEW BRITAIN REGION, P.N.G.   

P: 13APR2019 115036     7.0S  151.0E 4.0-5.6 AACAA  New Ireland                

 

The most unusual earthquake in the world today was an M 4.7 in north-central Siberia, Russia. It was not reported felt in this region. This is the first earthquake within about 300 km of this epicenter of M>=4.7 in at least 30 years.

 

O: 12APR2019 02:40:07  69.0N   99.5E ML=4.7  EMSC   NORTHCENTRAL SIBERIA, RUSSIA 

 

The largest earthquake in the U.S. or Canada today was an M 4.4 in Central Alaska north of Anchorage.  NEIC reported this earthquake of M 4.4 in Central Alaska was felt with intensity II-III in the area(s) of Alaska at Clear, Fairbanks, Anderson, Fort Wainwright, Healy, North Pole, Manley Hot Springs, Eielson AFB.  This is the strongest earthquake within about 150 km of today's epicenter since an M 4.7 on August 28, 2018 about 100 km northwest of today's event. Forecast 115227 had expected today's activity to the west in mid-April.

 

O: 11APR2019 10:42:45  64.7N  149.2W mb=4.4  EMSC   CENTRAL ALASKA               

P: 14APR2019 115227    65.1N  154.4W 3.2-5.1 BACAA  Northern Alaska            

 

The series of light earthquake on the Florida-Alabama area of the SE U.S. continued today with events of M 2.5, 2.6 and 2.8.  NEIC reported this earthquake of M 2.8 in Alabama was felt with intensity II-III in the area(s) of Flomaton, Alabama. This area saw an M 3.1 a month ago on March 11, 2019. At the time this reported noted in this regard:

 

 

"The most unusual earthquake in the U.S. today was an M 3.1 in southern Alabama. NEIC reported this earthquake of M 3.1 in Alabama was felt with intensity II-III in the area(s) of Century, Pensacola and Jay, Florida and in Mobile, Atmore and Brewton, Alabama.  Florida seldom feels tremor from earthquakes, so this is a significant regional event. The last earthquake within about 200 km of this epicenter with M>=3.1 occurred on February 18, 2011 and prior to that an M 3.1 on May 16, 2008." (March 11-12, 2019)

 

Forecasts 115117 and 115147 had expected today's activity was likely around April 12-17 within about 25 km of this epicenter.

 

O: 11APR2019 20:11:00  31.1N   87.2W mb=2.8  EMSC   ALABAMA                       

O: 12APR2019 03:51:21  31.1N   87.3W ML=2.6  EMSC   ALABAMA                      

O: 11APR2019 16:33:00  31.1N   87.3W mb=2.5  EMSC   ALABAMA                      

P: 12APR2019 115117    32.0N   87.0W 2.0-4.1 AAAAA  New Madrid area            

P: 17APR2019 115147    31.0N   87.0W 2.0-4.0 CAAAA  Southeast U.S.             

STRONG EARTHQUAKE OFF NORTHERN JAPAN

 

EARTHQUAKE SUMMARY FOR APRIL 10, 2019

 

The strongest earthquake in the world today was an M 6.1 off the coast of Northern Honshu, Japan. NEIC reported it was felt with intensity IV in Misawa, Aomori and II-III in Tokyo and Kakuda, Miyagi, Japan. This is the strongest earthquake in northern Japan in more than a year - the last such event within about 200 km of this epicenter being an M 6.2 on January 24, 2018. A similar inter-event time separated the previous such event of M 6.2 on November 11, 2016 from the January, 2018 earthquake (each 1 year and 2.5 months between).  Forecasts 114896 and 114880 had expected today's earthquake was likely within about 150 km of the epicenter in early April.

 

O: 11APR2019 08:18:19  40.4N  143.4E Mw=6.1  EMSC   OFF EAST COAST OF HONSHU, JAPA

P:  6APR2019 114896    40.0N  142.0E 3.5-5.5 BAAAA  Hokkaido, Japan            

P:  7APR2019 114880    39.0N  143.0E 4.0-5.4 BBAAA  So. of Honshu              

 

The strongest earthquake in the U.S. or Canada today occurred on the opposite side of the North Pacific. It was an M 4.7 off the coast of Oregon. It was reported with maximum intensity IV in Crescent City, California and I-II in Oregon at Florence, Brookings, Portland and Ashland.  This is the strongest earthquake off the Oregon coast within about 150 km of this epicenter since an M 6.2 on August 22, 2018. Two other such events have occurred in this area since 2016 - an M 5.5 on January 28, 2018 and an M 5.3 on July 29, 2018. Forecast 114913 had expected today's event was likely within about 50 km of the epicenter around April 10.

 

O: 10APR2019 14:11:32  44.2N  128.8W Mw=4.7  EMSC   OFF COAST OF OREGON          

P: 10APR2019 114913    43.9N  128.4W 3.0-4.4 AAAAA  Off Coast of Oregon        

 

An unusual earthquake of M 2.0 occurred today in Pennsylvania. This summary has previously linked earthquakes in this area with subsequent activity, including an enhanced possibility of, earthquakes in Southern California. This may be due to weather systems such as the weather bomb currently passing west and north of Pennsylvania. The largest earthquake in the past 30 years in this area of Pennsylvania was an M 4.2 and 4.6 on January 16, 1994. It was followed several hours later by the Northridge, California (M 6.7) earthquake of the same date. But other examples can be cited as well. An increase in seismicity in southern California is therefore expected during the next two days. California seismicity generally peaks in mid-April to early May and could do so again this year. The only other event within about 100 km of today's epicenter in the past eight years was an M 2.3 on April 23, 2017. Forecast 114915 had expected regional activity in early April.

 

O: 10APR2019 17:46:39  40.4N   76.1W ML=2.0  EMSC   PENNSYLVANIA                 

P:  3APR2019 114915    42.0N   80.0W 2.0-3.9 CBCAA  Ohio/Lake Erie             

 

 

 

 

SOUTH SANDWICH ISLANDS ENHANCEMENT CONTINUES

 

EARTHQUAKE SUMMARY FOR APRIL 9, 2019

 

A second strong earthquake in the past four days occurred today in the South Sandwich Islands. This event was at a shallow focus but was not reported felt. It occurred southeast of the normal large earthquakes in the area and is the strongest within about 150 km of today's epicenter since an 7.1 on December 11, 2018 and prior to that an M 6.7 on April 16, 2009. Forecast 115012 had expected this active southeast of the South Sandwich Islands was likely around April 7. When a strong quake of M 6.5 occurred on April 5, 2019, this summary noted:

 

"A strong M 6.5 occurred in the South Sandwich Islands today. It was not reported felt in this remote epicentral area. This may be a delayed reaction of strong tidal stresses in the area occurred with the previous full moon as noted in previous summaries:

 

 

"The full moon will arrive at 01:43 UT on March 21. Longitudes which area sub-lunar at this time are near 26 West and sub-solar at 154 East. These include the mid-Atlantic Ridge where a series of moderate earthquakes is occurring in the Azores, the South Sandwich Islands, and the region of Kamchatka and New Guinea among others. These will experience maximum tidal stresses but many areas are subject to tidal triggering outside these longitude zones. A strong tidal-related earthquake is likely in the next seven days. Tidally promoted events often occur with geomagnetic storms and/or near local solar noon or midnight." (March 18-25, 2019)

 

Today's event which occurred near local solar noon may have been promoted by the current geomagnetic storm and/or tidal stresses which maximize near this hour. An M 7.1 hit about 350 km southeast of this epicenter on December 11, 2018, but the last event in the South Sandwich Islands within about 200 km of today's epicenter with M>=6.5 occurred on May 28, 2016 with M 7.2 and prior to that on June 29, 2014. Forecast 115012 had expected today's event was likely within about 100 km  around April 5." (April 5, 2019)

 

The antipode to the South Sandwich Islands is at 59N 155E, a region north of Kamchatka, Russia. This region has been active in recent weeks and could see some triggered antipodal seismicity in the next several days.

 

O:  9APR2019 17:53:59  58.6S   25.5W Mw=6.5  EMSC   SOUTH SANDWICH ISLANDS REGION

P:  7APR2019 115012    61.0S   22.0W 4.0-5.7 ACBAA  Southern  Ocean            

 

An M 4.4 in Montana occurred after the M 6.5 in the South Sandwich Islands. NEIC reported this earthquake of M 4.4 in Western Montana was felt with intensity II III in the area(s) of Montana at Lima, Virginia City, Dillon, Sheridan, Ennis; in Idaho at Leadore, Moore, Salmon, Lewisville and Rexburg. An M 3.2 aftershock was felt with intensity IV in Lima, Montana and II-III in Dillon, Ennis, Butte and Helena and in Idaho at Moore, Salmon, Arco, Halley and Ketchum. The M 4.4 occurred 15 minutes 46 seconds after the M 6.5 in the South Sandwich Islands. This is the time it takes for a p-diff seismic wave to travel the 124 degrees from the South Sandwich Islands epicenter to the epicenter in western Montana. It is highly likely that this seismic wave (although relatively minor) triggered the M 4.4 in Montana as it passed through the region. The P-diff wave was the first to arrive from the South Sandwich Islands in Montana.  The earthquake of M 4.4 was followed by a strong series of aftershocks. An aftershock in Montana 20 minutes after the South Sandwich Islands event may have been triggered by P-reflections (PP waves). Aftershocks 25 minutes (SKS); 37 minutes (SS) and 39 minutes (ScS) may also have been triggered by seismic waves from the South Sandwich Islands.

 

Today's event of M 4.4 is the strongest in western Montana within about 150 km  of this epicenter since an M 4.4-4.6 about 50 km to the east occurred April 5, 2011. The last such event of significantly larger magnitude in the region occurred July 26, 2005 about 100 km north of this with M 5.5. Forecast 114902 had expected today's event within about 25 km of this epicenter was likely around April 11.

 

 

O: 09APR2019 18:33:32  44.7N  112.5W Ml=2.0  EMSC   WESTERN MONTANA

O: 09APR2019 18:18:13  44.7N  112.5W Ml=2.2  EMSC   WESTERN MONTANA

O: 09APR2019 18:30:45  44.7N  112.5W Ml=2.3  EMSC   WESTERN MONTANA

O: 09APR2019 23:17:16  44.7N  112.5W Ml=2.3  EMSC   WESTERN MONTANA

O: 09APR2019 18:13:52  44.7N  112.5W Ml=2.4  EMSC   WESTERN MONTANA

O: 09APR2019 18:08:46  44.7N  112.5W Mw=4.4  EMSC   WESTERN MONTANA

O:  9APR2019 18:11:14  44.7N  112.5W ML=3.2  EMSC   WESTERN MONTANA               

P: 11APR2019 114902    44.5N  112.6W 2.0-4.0 AAAAA  Montana/Idaho              

 

MODERATE QUAKES IN SAMOA

 

EARTHQUAKE SUMMARY FOR APRIL 8, 2019

 

Seismicity was active in most of the aftershock zones in Alaska where moderate earthquakes occurred today. The strongest earthquakes in the world today were an M 5.1 and 5.2 in the region of Tonga and Samoa. They were not felt in the region. The last such events of M>5.2 in the region of Tonga and Samoa within about 200 km of this epicenter occurred as an M 5.3 on February 15, 2019. Forecast 114970 had expected today's activity within about 50 km of these epicenters was likely around April 6.

 

O:  8APR2019 20:15:44  15.5S  173.0W mb=5.1  EMSC   TONGA                        

O:  8APR2019 23:05:53  15.6S  173.0W mb=5.2  EMSC   SAMOA ISLANDS REGION         

P:  6APR2019 114970    15.0S  173.0W 4.0-5.5 AAAAA  Samoa Islands              

 

An earthquake of M 3.9-4.2 shook the Dominican Republic today. NEIC reported it was felt with intensity II-III in Las Terrnas, Saman, El Carril, San Cristobal and Santo Domingo, Dominican Republic. It was preceded by foreshocks of M 3.1, 3.3 and 3.4. The last earthquake in the Dominican Republic within about 150 km of today's M 4.2 occurred on February 5, 2019 with M 4.4, an aftershock of an M 5.3 on February 4, 2019. Forecast 114813 had expected this activity was likely around April 4.

 

It appears that today's activity may have been promoted by antipodal effects from Tropical Cyclone Wallace. This had been expected in previous issues o this summary as:

 

"Some enhanced seismicity may accompany this storm in the antipodal area of the eastern Caribbean in the Leeward Islands north to the Virgin Islands and Puerto Rico. The current antipode is at 16N 64W." (April 6-8, 2019)

 

The eye of TC Wallace was at 17S 113E when the M 4.2 occurred in the Dominican Republic at 18N 69W within about 250 km of the exact antipode.

 

O:  8APR2019 19:56:00  18.2N   69.2W ML=3.1  EMSC   DOMINICAN REPUBLIC REGION    

O:  8APR2019 08:48:39  18.3N   68.8W ML=3.4  EMSC   DOMINICAN REPUBLIC           

O:  8APR2019 09:55:30  18.4N   69.7W ML=3.3  EMSC   DOMINICAN REPUBLIC REGION    

O:  8APR2019 23:30:45  18.8N   69.8W ML=4.2  EMSC   DOMINICAN REPUBLIC           

P:  4APR2019 114813    19.0N   71.0W 3.4-5.1 BAAAA  Puerto Rico                

 

The largest earthquakes in the U.S. or Canada today were an M 4.8 in the Gulf of Alaska; an M 4.7 in the Fox Islands, Alaska; an M 4.7 also in the Fox Islands; an M 4.0 near Kodiak Island, Alaska and  an M 4.6 in northern Alaska. NEIC reported the event in northern Alaska was felt with intensity II in Huslia and possibly in Wasilla, Alaska. Otherwise the other events were not reported felt. Each had been forecast within about 100 km to occur around April 7-10 (see forecasts 114932, 114953, 114925, and 114951).

 

O:  8APR2019 07:35:20  51.9N  169.6W mb=4.7  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P:  7APR2019 114932    52.4N  169.4W 3.5-4.9 AAAAA  Fox Islands, Aleutians     

 

O:  8APR2019 10:41:27  52.7N  167.0W mb=4.6  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P:  7APR2019 114932    52.4N  169.4W 3.5-4.9 AABAA  Fox Islands, Aleutians     

 

O:  8APR2019 19:57:41  56.4N  149.3W Mw=4.8  EMSC   GULF OF ALASKA               

P:  8APR2019 114953    55.0N  149.0W 3.0-5.1 ABAAA  Gulf of  Alaska            

 

O:  9APR2019 00:27:13  56.7N  153.0W mb=4.0  EMSC   KODIAK ISLAND REGION, ALASKA 

P:  9APR2019 114925    56.8N  155.7W 3.5-5.1 AABAA  Alaska Peninsula           

 

O:  8APR2019 15:24:14  65.4N  153.4W Mw=4.4  EMSC   NORTHERN ALASKA              

O:  9APR2019 03:03:11  66.3N  156.9W ml=3.3  EMSC   NORTHERN ALASKA              

O:  9APR2019 00:44:49  66.3N  157.0W ML=3.6  EMSC   NORTHERN ALASKA              

P:  4APR2019 114951    66.0N  156.0W 3.0-5.0 BAAAA  Northern Alaska            

 

MODERATELY LARGE M 5.7 EVENTS SHAKE  CHILE; WEST CHILE RISE

 

EARTHQUAKE SUMMARY FOR APRIL 7, 2019

 

Moderately strong quakes of M 5.7 each hit the regions of Central Chile and the West Chile Rise today. The moderately strong M 5.7 in Chile was widely felt in the Valparaiso and Santiago region of Chile today. NEIC reported maximum intensity VI in San Antonio and V in Valparaiso and Quilpue and II-III in Quillota, Santiago and La Ligua, Chile. CSN reported an aftershock of M 4.3 was felt with intensity V in  Coquimbo at Los Vilos; IV in Salamanca and III in Illapel; in Valparaiso III at Quillota and Zapallar, Chile. NEIC reported an aftershock of M 4.5 in Central Chile was felt with intensity IV in the area(s) of Illapel, Coquimbo, Chile. NEIC reported another aftershock of M 4.3 in Central Chile was felt with intensity II-III in the area(s) of San Antonio, Valparaiso, Chile. This is south of the moderate recent activity in this area of central Chile. This is the strongest earthquake within central Chile within about 200 km of this epicenter since an 5.9 about 200 km south of today's epicenter on July 4, 2017 and prior to that an M 6.9 and aftershocks of M 5.8 and 5.9 in late April, 2017. Forecast 114997 had expected today's event within this area was likely around April 5.

 

O:  7APR2019 10:52:40  33.8S   72.5W Mw=5.7  EMSC   OFFSHORE VALPARAISO, CHILE   

O:  7APR2019 12:20:45  33.8S   72.6W mb=4.3  EMSC   OFFSHORE VALPARAISO, CHILE   

P:  5APR2019 114997    34.0S   71.0W 4.0-5.5 AAAAA  Central Chile               

 

O:  8APR2019 06:39     32.1S   71.6W mb=4.6  GUC    Coquimbo at Los Vilos; IV in S

P:  9APR2019 114996    31.0S   71.0W 4.0-5.5 ABAAA  Central Chile              

 

The M 5.7 in the West Chile Rise was not reported felt in this remote oceanic area. At M 5.7 it is the largest earthquake in the West Chile Rise since a similar M 5.7 on December 25, 2015. No earthquakes of M>5.7 have hit within about 300 km of today's epicenter in the past 30 years. Forecast 115004 had expected today's event was likely within about 50 km of this epicenter around April 7.

 

O:  7APR2019 19:53:07  40.9S   85.7W mb=4.7  EMSC   WEST CHILE RISE              

O:  8APR2019 04:42:12  41.1S   90.6W mb=4.4  EMSC   SOUTHEAST OF EASTER ISLAND   

O:  7APR2019 15:45:08  41.4S   87.7W Mw=5.7  EMSC   WEST CHILE RISE              

P:  7APR2019 115004    41.0S   88.0W 4.0-5.5 AAAAA  Chile Rise                 

 

The strongest earthquake in the U.S. or Canada today was an M 5.5 in the Alaska Peninsula. It was not reported felt in this remote area. The last earthquake within about 200 km of this epicenter with M>=4.4 was an M 4.5 on March 26, 2019. The last with M>4.5 was an M 5.1 on February 15, 2019 following an M 6.0 on December 31, 2018. Today's event appears to be an aftershock of the December, 2018 quake. Forecast 114941 had expected today's earthquake within about 50 km was likely around April 4.

 

O:  8APR2019 00:00:59  54.5N  161.1W mb=4.4  EMSC   ALASKA PENINSULA             

P:  4APR2019 114941    54.5N  161.8W 3.5-5.0 BAAAA  Unimak Islands, Aleutians  

 

TROPICAL CYCLONES PROMOTE SIGNIFICANT SEISMICITY IN BANDA; GULF OF CALIFORNIA

 

EARTHQUAKE SUMMARY FOR APRIL 6, 2019

 

The largest earthquakes in the world today were an M 6.4 in the Banda Sea of Indonesia and an M 5.2 in the northern Gulf of California. These appear to have been promoted by Tropical Storms Wallace and Joaninha respectively. The earthquake in the Banda Sea was at an epicenter near the eye of Tropical Cyclone Wallace while the activity in the Gulf of California began when Tropical Cyclone Joaninha was at the antipode to that epicenter. This activity had been anticipated in several previous issues of this summary.

 

The earthquake of M 6.3 in the Banda Sea was not reported felt in that area. As noted, it occurred near the eye of Tropical Cyclone Wallace and was probably promoted from that source as noted in previous issues:

 

"A tropical cyclone may be forming in the Banda Sea, Indonesia. This system is currently located at 9S 130E with winds up to 33 kts and moving to the WSW at 9 kts. Some enhanced seismicity may accompany this storm in the Banda Sea area in the next several days." (April 3-4, 2019)

 

and

 

"Tropical cyclone Wallace continued in the Banda Sea, Indonesia with winds up to 55 kts. This system is currently moving to the WSW at 6 kts. Some enhanced seismicity may accompany this storm in the Banda Sea area in the next several days. This may include a strong earthquake." (April 5-6, 2019)

 

The last earthquake of M>=6.3 in the Banda Sea was an M 6.7 on October 24, 2017 and prior to that an M 6.3 on December 6, 2016. Forecast 114768 had expected this event was likely within this area around April 9.

 

O:  6APR2019 22:19:30   6.8S  125.0E mb=4.7  EMSC   BANDA SEA                    

O: 06APR2019 21:55:01   6.8S  125.0E mw=6.3  ANSS   Dili East Timor

O:  6APR2019 21:55:03   6.9S  125.1E Mw=6.3  EMSC   BANDA SEA                    

P:  9APR2019 114768     5.0S  126.0E 4.0-5.4 BBAAA  Ceram area                 

 

"Tropical cyclone Joaninha (22S) continued in the South Indian Ocean today with winds up to 075 kts. This system could enable further seismicity the the South Indian Ocean seafloor and ridges.  The antipodal area is in the North Pacific at 24N 111W near central Gulf of California where some seismicity may be promoted." (March 30, 2019).

 

TC Joaninha passed over the antipode to the northern Baja epicenters at 29N 113W  on March 31. The activity in Baja began shortly after that.   This summary has covered this activity since that time including comments in the previous issue:

 

 

"A series of light earthquakes also hit south of California in the northern Gulf of California today with M 3.1-3.7. This area often becomes active with strong geomagnetic excursions and this may have triggered today's activity. Forecast 114865 had expected this activity in early April. The last such events in the area were an M 4.3 on March 2, 2019 and an M 4.1 on October 17, 2018 after two years of inactivity in the region since September, 2016. A strong swarm hit the area on March 28, 2016 including an M 5.5 and 5.3." (April 3-4, 2019)

 

NEIC reported these earthquakes of M 4.1 and 5.2 in northern Gulf of California were felt with intensity II-IV in the area(s) of Puerto Penasco, Sonora, Mexico and possibly in Arizona.

 

O: 06APR2019 21:19:40  30.3N  113.4W ML=4.0  EMSC   GULF OF CALIFORNIA

O: 06APR2019 21:14:55  30.5N  114.3W ML=3.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 09:36:01  30.6N  114.2W ML=3.0  EMSC   GULF OF CALIFORNIA

O: 06APR2019 20:17:31  30.6N  114.3W ML=4.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 19:45:22  30.6N  114.3W ML=4.2  EMSC   GULF OF CALIFORNIA

O: 06APR2019 21:01:40  30.7N  114.1W Mw=5.2  EMSC   GULF OF CALIFORNIA

O: 06APR2019 09:25:46  30.7N  114.2W ML=3.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 08:25:12  30.7N  114.2W ML=3.2  EMSC   GULF OF CALIFORNIA

O: 06APR2019 21:34:14  30.7N  114.2W ML=4.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 07:23:40  30.7N  114.3W ML=3.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 20:20:49  30.7N  114.3W ML=3.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 21:41:56  30.8N  114.1W ML=3.2  EMSC   GULF OF CALIFORNIA

O: 06APR2019 08:37:02  30.8N  114.1W ML=4.2  EMSC   GULF OF CALIFORNIA

O: 06APR2019 08:45:13  30.8N  114.1W mb=4.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 08:56:54  30.8N  114.2W ML=3.1  EMSC   GULF OF CALIFORNIA

O: 06APR2019 08:03:40  30.8N  114.2W ML=4.0  EMSC   GULF OF CALIFORNIA

O: 06APR2019 22:14:33  30.8N  114.6W ML=3.2  EMSC   GULF OF CALIFORNIA

O:  6APR2019 20:01:54  30.9N  114.3W ML=3.1  EMSC   GULF OF CALIFORNIA           

O: 06APR2019 21:01:42  30.8N  114.1W mw=5.2  ANSS   Puerto Penasco Mexico

P:  8APR2019 114865    30.2N  114.1W 2.0-4.3 AAAAA  SW U.S.A                   

 

The strongest earthquake in the U.S. or Canada today was an M 4.5 in the Kodiak Island Region of Alaska. The last earthquake of M>=4.6 within about 200 km of this epicenter was an M 5.3 on May 11, 2018. Forecast 114925 had expected today's event in this area was likely around April 9.

 

O:  7APR2019 02:59:57  56.3N  154.2W Mw=4.5  EMSC   KODIAK ISLAND REGION, ALASKA 

O:  7APR2019 02:59:57  56.3N  154.2W Mw=4.6  ANSS   KODIAK ISLAND REGION, ALASKA 

P:  9APR2019 114925    56.8N  155.7W 3.5-5.1 AAAAA  Alaska Peninsula           

 

STRONG EARTHQUAKE IN THE SOUTH SANDWICH ISLANDS

 

EARTHQUAKE SUMMARY FOR APRIL 5, 2019

 

A strong M 6.5 occurred in the South Sandwich Islands today. It was not reported felt in this remote epicentral area. This may be a delayed reaction of strong tidal stresses in the area occurred with the previous full moon as noted in previous summaries:

 

 

"The full moon will arrive at 01:43 UT on March 21. Longitudes which area sub-lunar at this time are near 26 West and sub-solar at 154 East. These include the mid-Atlantic Ridge where a series of moderate earthquakes is occurring in the Azores, the South Sandwich Islands, and the region of Kamchatka and New Guinea among others. These will experience maximum tidal stresses but many areas are subject to tidal triggering outside these longitude zones. A strong tidal-related earthquake is likely in the next seven days. Tidally promoted events often occur with geomagnetic storms and/or near local solar noon or midnight." (March 18-25, 2019)

 

Today's event which occurred near local solar noon may have been promoted by the current geomagnetic storm and/or tidal stresses which maximize near this hour. An M 7.1 hit about 350 km southeast of this epicenter on December 11, 2018, but the last event in the South Sandwich Islands within about 200 km of today's epicenter with M>=6.5 occurred on May 28, 2016 with M 7.2 and prior to that on June 29, 2014. Forecast 115012 had expected today's event was likely within about 100 km  around April 5.

 

O:  5APR2019 16:14:19  55.9S   27.9W Mw=6.5  EMSC   SOUTH SANDWICH ISLANDS REGION

P:  5APR2019 115012    56.0S   27.0W 4.0-5.8 AAAAA  So. Sandwich Islands       

 

A moderately large M 5.8 also occurred south of Honshu, Japan in the Izu Islands of Japan today. No damage was reported with this earthquake which occurred in a remote area. Earthquake activity in this region occasionally migrates to the north following strong Izu Islands events. The area can also be affected by geomagnetic storms such as the one which continued today. The last event of M>=5.8 in the Izu Islands area of Japan within about 200 km of today's epicenter occurred November 16, 2017 (M 5.8). The last with greater magnitude was an M 6.5 on September 4, 2013. Forecast 114861 had expected moderate activity in this area in early April.

 

O:  5APR2019 09:56:53  30.4N  138.6E Mw=5.8  EMSC   IZU ISLANDS, JAPAN REGION    

P:  3APR2019 114861    30.0N  142.0E 4.0-5.5 AACAA  Off East Coast Honshu      

 

An M 3.5 near Parkfield, California today was widely felt. NEIC reported intensity IV in California at Shandon and Bradley and II-III in San Miguel, Coalinga, Paso Robles, Templeton, Atascadero, Morro Bay, San Luis Obispo and Los Osos, California. The last earthquake in the Parkfield, CA area within about 50 km of this epicenter with M>=3.5 occurred on November 27, 2018 (M 4.0) and prior to that on August 14, 2018 (M 3.5). Forecasts 114839 had expected a moderate earthquake was possible in the area around April 7-8. The Parkfield area within about 35 km of this epicenter last saw a moderate event on August 6, 2012 (M 4.4).

 

O:  5APR2019 17:52:32  35.9N  120.4W Mw=3.5  EMSC   CENTRAL CALIFORNIA           

O:  5APR2019 22:28:29  36.0N  120.5W Md=2.1  EMSC   CENTRAL CALIFORNIA           

P:  7APR2019 114839    36.6N  120.7W 2.5-4.4 AAAAA  Central California         

P:  8APR2019 114839    36.2N  120.8W 2.5-4.4 BAAAA  Central California         

 

The current swarm in the northern Gulf of California continued unabated today with events of M 4.0-4.5. In previous issues of this summary, this had been noted as:

 

 

"A series of light earthquakes also hit south of California in the northern Gulf of California today with M 3.1-3.7. This area often becomes active with strong geomagnetic excursions and this may have triggered today's activity. Forecast 114865 had expected this activity in early April. The last such events in the area were an M 4.3 on March 2, 2019 and an M 4.1 on October 17, 2018 after two years of inactivity in the region since September, 2016. A strong swarm hit the area on March 28, 2016 including an M 5.5 and 5.3." (April 3-4, 2019)

 

O:  5APR2019 21:31:10  30.2N  114.2W ML=4.5  EMSC   GULF OF CALIFORNIA           

O:  5APR2019 20:37:24  30.4N  114.4W ML=4.1  EMSC   GULF OF CALIFORNIA           

O:  5APR2019 20:53:38  30.5N  114.4W ML=4.0  EMSC   GULF OF CALIFORNIA           

O:  5APR2019 21:45:26  30.6N  114.3W ML=4.1  EMSC   GULF OF CALIFORNIA           

O:  6APR2019 00:26:07  30.8N  114.1W ML=4.2  EMSC   GULF OF CALIFORNIA           

O:  5APR2019 20:20:15  30.9N  114.6W ML=3.8  EMSC   GULF OF CALIFORNIA           

P:  8APR2019 114865    30.2N  114.1W 2.0-4.3 BAAAA  SW U.S.A                   

 

MODERATE QUAKES SHAKE TURKEY

 

EARTHQUAKE SUMMARY FOR APRIL 4, 2019

 

The most active area in the world today was Turkey where an M 4.8-5.3 shook regions in the east and an M 4.4 in the west of Turkey.  NEIC reported the earthquake of M 5.3 in Eastern Turkey was felt with intensity II-III in the area(s) of Gaziantep, Turkey. The earthquake of M 4.8 in eastern Turkey was the strongest within about 200 km of that epicenter since an M 5.6 shook the region on March 2, 2017 and prior to that on December 2. 2015 with M 5.5 The event in western Turkey of M 4.4 was part of the aftershock sequence of the M 5.7 of March 20, 2019. It is the second largest aftershock to date after an M 5.0 on March 31, 2019. The activity in western Turkey is at 104 degrees from the M 7.5 in Ecuador of February 22, 2019 and was probably promoted by energy from that event. Forecasts 114885 and 114886 had expected this activity in Turkey was likely around April 4-5 within about 100 km of each epicenter.

 

O:  4APR2019 15:01:18  37.5N   29.4E mb=4.4  EMSC   WESTERN TURKEY               

P:  4APR2019 114885    38.0N   29.0E 3.5-5.2 AAAAA  Turkey                     

 

O:  4APR2019 17:31:11  38.4N   39.1E mb=4.8  EMSC   EASTERN TURKEY               

O:  4APR2019 17:31:11  38.3N   39.2E mb=5.3  ANSS   EASTERN TURKEY               

P:  5APR2019 114886    39.0N   40.0E 3.5-4.9 AAAAA  Turkey                     

 

An earthquake of M 5.3 also shook areas of Myanmar and India today. NEIC reported this earthquake of M 5.3 in India-Myanmar was felt with intensity V in Mariani, Assam, India; IV in Dimapur, Nagaland, and Gauhati, Assam, India and II-III in the area(s) of India at Manipur, Golaghat, Jorhat, Silchar, Shillong and Aizawi. This is the strongest earthquake within about 200 km of this epicenter since an M 6.6 on January 7, 2018 and prior to that an M 5.7 on January 3, 2017. Forecast 114540 had expected today's activity at the end of March or early April in this area.

 

O:  4APR2019 07:45:29  25.5N   94.4E mb=5.3  EMSC   MYANMAR-INDIA BORDER REGION  

P: 31MAR2019 114540    24.0N   94.0E 4.0-5.4 BBAAA  Myanmar                    

 

The strongest earthquakes in the U.S. or Canada today were a pair of M 3.7 events in the aftershock zone in the Gulf of Alaska. These were not reported felt in this remote region. This remains an active seismic zone following the M 7.9 of January 23, 2018. The last event of M>=3.7 in the area was an M 4.0 on March 15, 2019. Forecast 114953 had expected today's event was likely in early April.

 

O:  4APR2019 13:55:35  56.4N  149.1W ML=3.7  EMSC   GULF OF ALASKA               

O:  4APR2019 12:19:19  56.4N  149.1W ml=3.7  EMSC   GULF OF ALASKA               

P:  8APR2019 114953    55.0N  149.0W 3.0-5.1 BBAAA  Gulf of  Alaska            

 

Enhanced seismicity continued today in the northern Gulf of California with moderate events of M 4.3 and 4.5 among others. In the previous issue of this summary this had been noted as:

 

 

 -61.0  -22.0 27  4  7 2019    4.0-5.7  Southern  Ocean                  3 2 115012 608

 

O:  4APR2019 22:55:23  30.6N  114.4W ML=4.3  EMSC   GULF OF CALIFORNIA           

O:  4APR2019 22:43:33  30.6N  114.5W ML=4.5  EMSC   GULF OF CALIFORNIA           

P:  8APR2019 114865    30.2N  114.1W 2.0-4.3 BAAAA  SW U.S.A                   

 

Today's earthquake and forecast map follows. Stippled White areas are nodal distances (360/n, n an integer) from the earthquake of M 7.0 in Peru March 1, 2019 where promoted seismicity is considered likely.

 

"A series of light earthquakes also hit south of California in the northern Gulf of California today with M 3.1-3.7. This area often becomes active with strong geomagnetic excursions and this may have triggered today's activity. Forecast 114865 had expected this activity in early April. The last such events in the area were an M 4.3 on March 2, 2019 and an M 4.1 on October 17, 2018 after two years of inactivity in the region since September, 2016. A strong swarm hit the area on March 28, 2016 including an M 5.5 and 5.3." (April 3-4, 2019)

 

LOS ANGELES, CA M 3.6 TRIGGERS M 2.5 OFF SAN FRANCISCO

 

EARTHQUAKE SUMMARY FOR APRIL 3, 2019

 

An earthquake of M 3.6 was widely felt in the region of Los Angeles, California today. NEIC reported it was felt with maximum intensity V in Anahein and IV in Yorba Linda, Orange and II-II in Chino Hills, Villa Park, Brea, Santa Fe, Los Alamitos, Corona, Aliso Viejo, Newport, Huntington Beach, Newport Beach and in general within about 50 km of the epicenter. The last earthquake within about 50 km of this epicenter in the greater Los Angeles area was an M 4.4 on August 29, 2018 about 40 km north of today's epicenter. Forecast 114871 had expected today's event was likely within about 10 km of this epicenter around April 2.

 

O:  3APR2019 12:06:22  33.9N  117.7W ML=3.6  EMSC   GREATER LOS ANGELES AREA, CALI

O:  3APR2019 12:37:29  33.9N  117.7W Ml=2.3  EMSC   GREATER LOS ANGELES AREA, CALI

P:  2APR2019 114871    33.8N  117.7W 2.5-4.6 AAAAA  So. California             

 

The earthquake in Los Angeles was followed by an M 2.5 in the San Pablo Bay area near San Francisco 2 minutes and 34 seconds later. The distance of 5.5 degrees between these two events takes S- and P-waves 2.5 minutes to traverse. It would therefore appear that this event in Central California was triggered by waves from Los Angeles. As it was widely felt, it is not a ghost event - a misreading of seismic traces from a distant event as a local event. The area of the San Pablo Bay has seen increased seismicity in the past week. That a minor earthquake could be triggered by light seismic waves from Los Angeles suggests that the region is under considerable stress at this time. This could indicate this as the initiating point for a near-term moderate or large earthquake. Such an event, as today's would probably be associated with strong geomagnetic disturbance, a strong solar flare or high tidal stresses. A series of earthquakes of M 2.5-3.0 hit the area to the north and east of this on March 30, 2019 (M 2.9, 2.9, 2.7 and 2.6) after an M 2.8 and 2.6 on March 27, 2019 at today's epicenter. Forecast 114842 had expected regional activity around April 4.

 

NEIC reported this earthquake of M 2.5 west of San Francisco, California  was felt with intensity II-III in the area(s) of California at Napa, Oakland, San Francisco and South San Francisco.

 

O:  3APR2019 12:08:54  38.1N  122.4W Md=2.5  EMSC   SAN PABLO BAY, CALIFORNIA    

P:  4APR2019 114842    38.9N  122.8W 2.5-4.7 AAAAA  Central California         

 

A series of light earthquakes also hit south of California in the northern Gulf of California today with M 3.1-3.7. This area often becomes active with strong geomagnetic excursions and this may have triggered today's activity. Forecast 114865 had expected this activity in early April. The last such events in the area were an M 4.3 on March 2, 2019 and an M 4.1 on October 17, 2018 after two years of inactivity in the region since September, 2016. A strong swarm hit the area on March 28, 2016 including an M 5.5 and 5.3.

 

O: 03APR2019 10:01:45  30.7N  114.2W ML=3.2  EMSC   GULF OF CALIFORNIA

O: 03APR2019 09:42:07  30.7N  114.2W ML=3.7  EMSC   GULF OF CALIFORNIA

O: 03APR2019 16:19:17  30.9N  114.2W ML=3.5  EMSC   GULF OF CALIFORNIA

O:  3APR2019 08:49:05  30.7N  114.2W ML=3.1  EMSC   GULF OF CALIFORNIA           

P:  8APR2019 114865    30.2N  114.1W 2.0-4.3 BAAAA  SW U.S.A                   

 

The strongset earthquake in the U.S. or Canada today was an M 4.3 aftershock in the Rat Islands, Alaska. An M 6.4-6.5 hit this area yesterday. Today's event

had been expected in forecast 114938 to occur around April 3.

 

O:  3APR2019 11:15:51  51.8N  177.8E mb=4.3  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P:  3APR2019 114938    52.0N  177.0E 4.0-5.8 AAAAA  Rat Islands                

 

An unusual earthquake of M 4.4 hit the Pyrenees of Spain today. NEIC reported this earthquake of M 3.7-4.4 in Spain was felt with intensity II-III in the area(s) of La Massana La Lassana, Andorra. The last earthquake of M>=4.4 within about 200 km of this epicenter was an M 4.5 12 years ago on November 15, 2007 and prior to that an M 5.1 on September 21, 2004. Forecast 114618 had expected a moderate earthquake in this area in late March or early April.

 

O:  3APR2019 15:29:51  42.3N    1.3E ML=4.4  EMSC   PYRENEES                     

P: 26MAR2019 114618    42.0N    3.0E 3.0-5.3 CABAA  France                     

 

STRONG EARTHQUAKE RATTLES RAT ISL:ANDS, ALEUTIANS, ALASKA

 

EARTHQUAKE SUMMARY FOR APRIL 2, 2019

 

A strong M 6.4-6.5 quake shook the Rat Islands in the western Aleutians, Alaska today. It was followed by a strong series of aftershocks. None of these were reported felt in this remote area. When this area saw an M 4.9 foreshock yesterday, this summary noted:

 

 

"The strongest earthquake in the U.S. or Canada today was an M 4.9 in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote area. This is the strongest earthquake in the Rat Islands since an M 5.1 on March 2, 2018 more than a year ago. Forecast 114674 had expected today's event within about 50 km of this epicenter was likely around March 31." (April 1-2, 2019)

 

Today's event may have been triggered by a strong geomagnetic storm which  maximized near the time of the Rat Islands mainshock. This summary had expected enhanced seismicity at high latitudes such as the Rat Islands in association with this storm as:

 

"High latitude geomagnetic field also active to minor storm conditions  with AP at 22.  The minor geomagnetic storm which began March 31, especially at high latitudes and maximizing near mid-day could bring enhanced global seismicity over the next two days near the geomagnetic equator and at high latitudes." (March 30-April 2, 2019)

 

The coming new moon may also have promoted today's event which occurred near local solar noon, a prime time for tidal effects on seismicity. The forecast, which included portions of Alaska, related to the new moon has read:

 

 

"The new moon will arrive on April 5, 2019 at 08:50 UT. Longitudes which are at solar midnight at this time are near 130 West longitude while those at solar

noon are near 50 East longitude. These include areas of eastern Alaska and western North America in the west and Turkey and Iran in the east. These regions are most likely to see tidal triggering with this new moon but many other areas are subject to tidal triggering as well. Tidally triggered events are most likely near local solar midnight and local solar noon." (March 31-April 2, 2019)

 

 

The last earthquake in the Rat Islands of M>=6.5 was an M 6.6 on October 8, 2017. Today's shallow focus event, however is the strongest at a shallow depth since an M 6.8 on June 14, 2005 in  the Rat Islands. An intermediate focus M 7.9 hit the region to the south on June 23, 2014, the only other such regional events in the past 13 years. Forecasts 114674 and 114938 had expected a strong earthquake within about 100 km of today's epicenter was likely at the end of March or in early April. Today's activity is located at  101 degrees from the last major earthquake in the world - the M 7.5 in Ecuador of February 22, and was probably promoted by strongly concentrated seismic energy at this distance from that event.

 

 

O: 03APR2019 02:51:14  51.8N  177.9E mb=4.2  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

O: 02APR2019 23:28:50  51.8N  178.0E mb=4.6  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

O: 02APR2019 21:39:40  51.8N  178.1E mb=5.2  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

O: 03APR2019 01:03:43  51.9N  178.1E mb=4.2  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

O: 02APR2019 21:46:24  52.0N  178.0E mb=4.7  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

O: 02APR2019 23:13:38  52.1N  178.2E mb=4.2  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

O: 02APR2019 21:35:32  52.2N  178.0E mw=6.5  ANSS   Kiska Volcano Alaska

O: 02APR2019 21:35:32  52.2N  178.1E Mw=6.4  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P:  2APR2019 114938    51.0N  178.0E 4.0-6.0 ABAAA  Rat Islands                

P: 31MAR2019 114674    52.0N  179.0E 4.0-5.6 AAAAA  Rat Islands                

 

A moderately strong earthquake also shook the whole of Taiwan today. This event of M 5.4 is the strongest in Taiwan since an M 5.7 and 5.8 on October 23, 2018 and prior to that an M 6.4 on February 6, 2018. CWB reported this earthquake was felt with intensity IV in Kaohsiung, Pingtung, Chiayi; III in Taitung, Tainan, Hualien, Yunlin, Nantou, Taichung; II in Changhua, Penghu, Miaoli, Yilan, Hsinchu, Taipei and I in Taoyuan and Hsinchu Counties, Taiwan. NEIC reported this earthquake of M 5.4 in Taiwan was felt with intensity V in Pingtung; IV in Kaohsiung, and II-III in the area(s) of Taitung, Chiayi, Tainan, Yunlin, Taichung and Hsinchu, Taiwan. Forecast 114831 had expected moderatly large earthquakes in Taiwan in early April.

 

O:  3APR2019 01:52:56  23.0N  120.9E Mw=5.4  EMSC   TAIWAN                       

O:  3APR2019 01:52:55  23.0N  120.9E ML=5.6  TAI    Hualien, Taiwan              

P:  2APR2019 114831    23.0N  122.0E 4.0-5.6 AAAAA  Taiwan                     

 

STRONG SEISMICITY CONTINUES IN SOUTH INDIAN RIDGES

 

EARTHQUAKE SUMMARY FOR APRIL 1, 2019

 

The strongest earthquake of the day was an M 6.0 in the Mauritius/Reunion region of the South Indian Ocean. This is a volcanic center and this may be related to regional volcanism in the Reunion area. This is the strongest earthquake within about 250 km of this epicenter since an M 6.0 on July 19, 2017 and prior to that an M 6.7 on July 26, 2012. Forecast 114709 expected this area to be active at the end of March. An M 5.9 hit north of this epicenter on  March 30, 2019. At the time, this summary noted it as:

 

 

"The earthquake of M 5.9 in the Mid-Indian Ridge occurred about 8 minutes after the event in northern Hawaii. This is not sufficient time for seismic waves to make the 140 degree journey from one to the other, but external effects from geomagnetic disturbances could have helped promote both events. The earthquake in the Mid-Indian Ridge occurred near local solar noon and may also have been promoted by tidal effects which maximize at this hour. Forecast 114709 had expected enhanced activity in this region in late March. Part of this was due to the presence of Tropical Cyclone Joaninha as noted in previous issues of this summary:

 

"Tropical cyclone Joaninha (22S) continued in the South Indian Ocean today with winds up to 70 kts. This system could enable further seismicity the the South Indian Ocean seafloor and ridges." (March 23-27, 2019)

 

This is the strongest earthquake in the Mid-Indian Ridge within about 250 km of this epicenter since an M 5.9 on December 2, 1998. Only two other such quakes have occurred in the area in the past 30 years - an M 6.1 on March 22, 1990 and an M 5.9 on February 22, 1990. This epicenter is at 103 degrees from the M 7.3 Komandorsky Island earthquake of December 20, 2018 and may have been promoted from that source." (March 30, 2019)

 

 

O:  1APR2019 18:39:08  18.1S   65.4E Mw=6.0  EMSC   MAURITIUS - REUNION REGION   

P: 22MAR2019 114709    17.0S   67.0E 4.0-5.6 CBBAA  So. Indian Ocean           

 

The earthquake swarm in the Nicobar Islands, India continued today with the  largest event in the swarm an M 5.5. While this is a major swarm for the area, it is unlikely to produce a major quake. There has probably been insufficient time to build up stress after the Boxing Day (December 26, 2004) M 9.2 for another major quake at this epicenter at this time.

 

O:  1APR2019 07:49:32   7.4N   94.5E ML=4.0  EMSC   NICOBAR ISLANDS, INDIA REGION

O:  1APR2019 10:14:13   7.4N   94.9E ML=4.4  EMSC   NICOBAR ISLANDS, INDIA REGION

O:  1APR2019 08:11:31   7.5N   94.2E Mw=5.5  EMSC   NICOBAR ISLANDS, INDIA REGION

O:  1APR2019 07:37:49   7.5N   94.3E mb=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O:  1APR2019 16:28:26   7.5N   94.7E ML=4.3  EMSC   NICOBAR ISLANDS, INDIA REGION

O:  1APR2019 14:40:00   7.6N   94.3E ML=4.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O:  1APR2019 08:05:08   7.6N   94.5E ML=4.3  EMSC   NICOBAR ISLANDS, INDIA REGION

P: 31MAR2019 114477     4.0N   95.0E 4.0-5.6 ACAAA  Nicobar Islands            

 

An earthquake of M 5.2 in the Iraq-Iran border region today was followed by moderate aftershocks of M 4.7 and 4.9 among others.  NEIC reported these earthquakes of M 4.9 and 5.2 in Iraq were felt with intensity II-III in the area(s) of Baghdad, Iraq.  A series of shocks in this area occurred about 100 km north of this beginning in August, 2018 (M 6.0) and November 25, 2018 (M 6.3). This migrated to the south within about 75 km of today's event on January 6, 2019 (M 5.6). The last events of M>=5.2 within about 100 km of today's epicenter occurred last year with a swarm of M 5.2-5.5 on January 11, 2011. Forecast 114597 had expected today's events within about 100 km was likely at the end of March or in early April.

 

O:  1APR2019 10:07:23  33.5N   45.7E Mw=5.2  EMSC   IRAN-IRAQ BORDER REGION      

O:  1APR2019 10:53:32  33.6N   45.6E mb=4.7  EMSC   IRAN-IRAQ BORDER REGION      

O:  1APR2019 10:16:14  33.7N   45.8E mb=4.9  EMSC   IRAN-IRAQ BORDER REGION      

P: 28MAR2019 114597    33.0N   46.0E 3.8-5.4 BAAAA  So. Iran                   

 

The strongest earthquake in the U.S. or Canada today was an M 4.9 in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote area. This is the strongest earthquake in the Rat Islands since an M 5.1 on March 2, 2018 more than a year ago. Forecast 114674 had expected today's event within about 50 km of this epicenter was likely around March 31.

 

O:  2APR2019 00:59:19  52.0N  178.2E mb=4.9  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 31MAR2019 114674    52.0N  179.0E 4.0-5.6 AAAAA  Rat Islands                

 

An earthquake of M 3.6 south of the Aleutian Islands today may have been an outer rise event. These are caused by buckling of the subducting plate due to an obstruction in the subduction zone. The have been proposed as a precursor to large subduction zone events. If this is such, the earthquake would occur within the year near 52N 171W. Forecast 114663 had expected today's event to the north around March 27. In the past year four such events of M 4.1-4.2 have occurred in the region, mostly to the west by about 100 km near 172,5W.

 

O:  1APR2019 15:44:03  50.8N  171.3W mb=3.6  EMSC   SOUTH OF ALEUTIAN ISLANDS     

P: 27MAR2019 114663    52.1N  171.3W 3.5-5.0 BBAAA  Andreanoff Isls, Aleutians 

 

ANTIPODAL QUAKES IN PERU/NICOBAR AND ECUADOR/SUMATRA

 

EARTHQUAKE SUMMARY FOR MARCH 31, 2019

 

Two major groups of antipodal earthquakes occurred today, perhaps triggered by a strong increase in the disturbance in the geomagnetic field. This series began with an M 6.2 near the coast of Ecuador within minutes of local solar  midnight, a prime time for geomagnetic effects on seismicity. It was followed about 12 hours later by an M 4.6 also near local solar midnight in northern Sumatra within about 100 km of the exact antipode of the Ecuador event.  The other series began with an M 5.6 off the coast of Northern Peru. This was followed by a strong series of moderate earthquakes in the Nicobar Islands, India near the antipode to the Peruvian quake which occurred near local solar noon.  Antipodal activity often occurs during strong geomagnetic excursions and this appears to be the case in the current circumstance.

 

The strongest earthquake of the day was the M 6.2 in the area west of Ecuador. NEIC reported it was felt with maximum intensity VI in Ecuador at Pajan; V in Santa Elena; IV in Jipijapa, Santa Lucia, Guayquil, Portoviejo, Manta and Bahia de Caraquez and II-III in El Triunfo and Eloy Alfaro, Ecuador. NEIC reported an aftershock of M 5.4 off the coast of Ecuador  was felt with intensity IV in Guayaquil, Guayas, Ecuador and II-III in the area(s) of Jipijapa, Manabi, Ecuador. This is the strongest earthquake off Ecuador within about 200 km of this epicenters since an M 6.3 on May 21, 2006. A larger event of M 7.2 occurred about 200 km north of this on August 4, 1998. Forecast 114484 had expected today's activity was likely within about 100 km around March 31.

 

O: 31MAR2019 07:32:27   1.7S   80.1W ML=4.5  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 07:27:17   1.9S   80.7W mb=4.8  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 07:35:39   1.9S   81.1W ML=4.3  EMSC   OFF COAST OF ECUADOR

O: 31MAR2019 07:28:49   2.0S   80.8W Mw=5.5  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 20:34:54   2.0S   80.9W ML=4.0  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 07:04:03   2.0S   80.9W Mw=6.2  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 14:09:11   2.0S   80.9W mb=5.0  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 07:08:51   2.0S   81.0W mb=5.0  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 07:45:24   2.0S   81.1W ML=4.3  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 08:53:41   2.0S   81.1W ML=4.6  EMSC   NEAR COAST OF ECUADOR

O: 31MAR2019 11:03:57   2.0S   81.2W ML=4.1  EMSC   OFF COAST OF ECUADOR         

P: 31MAR2019 114484     1.0S   81.0W 4.0-5.4 AAAAA  Ecuador                    

 

An event antipodal to the Ecuador activity occurred about 12 hours later in northern Sumatra with M 4.6. Forecast 114476 had expected this event was likely within  about 100 km around March 31.

 

O: 31MAR2019 18:31:19   2.1N   97.9E mb=4.6  EMSC   NORTHERN SUMATRA, INDONESIA  

P: 31MAR2019 114476     2.0N   97.0E 4.0-5.4 AAAAA  Nicobar Islands            

 

A moderately strong M 5.6 off the coast of Northern Peru followed the M 6.2 in  Ecuador about 8 hours later.  NEIC reported this earthquake of M 5.5 off western northern Peru  was felt with intensity II-III in the area(s) of Peru at Chimbote and Trujillo.  The last earthquake of M>=5.6 within about 200 km of this epicenter was an M 5.6 on April 26, 2015 and before t6hat an M 5.7 on July 4, 2010. Forecast 114491 expected today's event in this area was likely at the end of March or early April.

 

O: 31MAR2019 15:27:55   9.8S   79.3W mb=5.6  EMSC   OFF COAST OF NORTHERN PERU   

P: 27MAR2019 114491     9.0S   81.0W 4.0-5.6 BABAA  No. Peru                   

 

A highly unusual series of moderately strong earthquakes occurred today in the Nicobar Islands, India. About 35 events were recorded in this series. No damage was reported. The largest of these were three of M 5.2. The last activity of this type in the Nicobar Islands was an M 6.4 and associated shocks of November 8, 2015. This activity is located in the zone where the M 9.2 earthquake and tsunami occurred on December 26, 2004 and appears to be the strongest swarm in the region since that time. Forecast 114477 had expected this activity in the Nicobar Islands was likely at the end of March.

 

O: 01APR2019 03:15:48   7.3N   94.9E ML=4.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 03:54:23   7.4N   94.2E mb=4.5  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 02:49:42   7.4N   94.2E mb=4.7  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 06:02:13   7.4N   94.9E ML=4.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 03:38:06   7.5N   94.1E mb=5.0  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:58:18   7.5N   94.2E mb=4.7  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 04:09:13   7.5N   94.2E mb=5.0  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:44:25   7.5N   94.3E mb=4.6  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 03:21:39   7.5N   94.3E mb=4.6  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 03:22:53   7.5N   94.4E mb=4.5  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 31MAR2019 23:42:45   7.5N   95.0E ML=4.7  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 01:21:30   7.6N   94.1E Mw=5.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 01:23:58   7.6N   94.2E Mw=5.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 05:09:16   7.6N   94.2E mb=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 05:52:38   7.6N   94.3E Mw=5.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 02:02:43   7.6N   94.3E mb=4.5  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:37:27   7.6N   94.3E mb=4.7  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:49:37   7.6N   94.3E mb=4.8  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 01:08:06   7.6N   94.3E mb=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 01:11:43   7.6N   94.3E mb=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 31MAR2019 23:32:20   7.6N   94.4E mb=4.5  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:34:09   7.6N   94.4E mb=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:03:42   7.7N   94.2E Mw=5.1  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 31MAR2019 23:56:47   7.7N   94.3E ML=4.6  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:25:43   7.7N   94.3E Mw=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 04:30:27   7.7N   94.3E mb=4.3  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 00:23:37   7.7N   94.3E mb=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 31MAR2019 23:44:43   7.7N   94.3E mb=5.2  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 06:56:40   7.7N   94.4E mb=4.6  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 01:34:20   7.7N   94.4E mb=4.7  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 01APR2019 04:04:28   7.9N   94.0E ML=4.3  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 31MAR2019 23:46:41   7.9N   94.1E Mw=5.1  EMSC   NICOBAR ISLANDS, INDIA REGION

O: 31MAR2019 23:59:52   8.5N   94.2E Mw=4.9  EMSC   NICOBAR ISLANDS, INDIA REGION

P: 22MAR2019 114477     6.0N   93.0E 4.0-5.7 CCAAA  Nicobar Islands            

P: 31MAR2019 114477     4.0N   95.0E 4.0-5.6 ACAAA  Nicobar Islands            

 

A moderately large M 5.4 was also widely felt in central Leyte, Philippines today. PHIVOLCS reported this earthquake was felt with intensity V in Loreto, Dinagat Islands; IV Silago, Southern Leyte; III in Surigao City; San Jose, Dinagat Islands, Limasawa, San Francisco, San Juan, Hinunangan and Maasin City, Southern Leyte; Tacloban City, Ormoc City, Palo, Hilongos, Bato, Hindang, Babatngon, Javier, MacArthur, Tanauan, Matalom, Abuyog, Isabel, Capoocan and Dagami, Leyte, Lawaan, Eastern Samar, Philippines. NEIC reported this earthquake of M 5.5 in Leyte, Philippines was felt with intensity IV in Pawing and Palo Eastern Visayas and II-III in the area(s) of Brasilisa, Caraga, Anahawan, San Antonio, Tabunck and Silanga, Eastern Visayas, Philippines. This epicenter, like that of activity in Nicobar Islands, India and Peru is located near the geomagnetic equator and may have been triggered by today's geomagnetic storm. The last event in Leyte within about 150 km of this epicenter with M>=5.4 occurred in northern Mindanao as an M 6.0 on March 8, 2019, the last

in Leyte was an M 5.4 on August 24, 2018. Forecast 114515 had expected today's event within about 50 km was likely around

March 30.

 

O:  1APR2019 02:16:55  10.6N  125.9E Mw=5.5  EMSC   LEYTE, PHILIPPINES           

O: 01APR2019 02:16:53  10.6N  126.0E MS=5.4  PHI  Felt with intensity V

P: 30MAR2019 114515    11.0N  126.0E 3.5-5.2 AAAAA  Luzon, Philippines         

 

Activity such as this near the geomagnetic equator was expected with a minor geomagnetic storm which occurred near mid-day today. It is likely to have  promoted these series. This had been noted in previous issues of this summary as:

 

"A minor geomagnetic storm is likely during March 31, especially at high latitudes and maximizing near mid-day. This could bring enhanced global seismicity over the next two days near the geomagnetic equator and at high latitudes." (March 30-31, 2019)

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in Central Alaska north of Anchorage. NEIC reported this earthquake of M 4.2 in Central Alaska was felt with intensity II-III in the area(s) of Talkeetna, Wasilla, Anchorage, Eagle River, Alaska. This is the strongest earthquake within about 100 km of this epicenter since an M 4.5 on November 30, 2018 and before that an M 4.2 on August 15, 2018. Forecast 114689 had expected today's activity was likely in late March.

 

O: 31MAR2019 14:41:36  62.2N  151.2W mb=4.2  EMSC   CENTRAL ALASKA               

P: 26MAR2019 114689    62.9N  150.2W 3.2-4.9 BAAAA  Central Alaska             

 

An earthquake of M 3.1 shook the Northridge, California area today and was followed by aftershocks of M 2.1 and 2.1. Earthquakes of M>=3 have been rare in the Northridge area in recent months, but the area is probably ripe for a strong earthquake as it has been more than 25 years since the M 6.7 in Northridge in January, 1994. The area often experiences strong earthquakes with interevent times around 22-25 years. The last earthquake of M>=3.1 in the area 34-35N 118 119W which includes the western valleys of Los Angeles was an M 3.1-3.3 on December 8, 2017. NEIC reported this earthquake of M 3.1 in Northridge, California was felt with intensity II-III in the area(s) of Northridge, North Hills, Reseda, Panorama, Van Nuys, Winnetka, Encino, Granada Hills, California.

Forecast 114588 had expected today's activity was possible around March 31.

 

O: 31MAR2019 10:28:03  34.4N  118.6W Ml=2.1  EMSC   GREATER LOS ANGELES AREA, CALI

O:  1APR2019 00:25:00  34.2N  118.5W Ml=2.1  EMSC   GREATER LOS ANGELES AREA, CALI

O: 31MAR2019 10:52:46  34.2N  118.5W Ml=3.1  EMSC   GREATER LOS ANGELES AREA, CALI

P: 31MAR2019 114588    33.6N  118.5W 2.5-4.6 AAAAA  So. California             

 

APRIL SEISMICITY LIKELY TO BE ENHANCED OVER MARCH, 2019

 

EARTHQUAKE SUMMARY FOR MARCH 30, 2019

 

During the past decade the first two weeks of April have shown an extraordinary

enhancement in global seismicity. This may be related to seasonal effects of weather systems at this change of season. Whatever the cause, it is likely that this enhancement will continue this year as March has been a very quiet month in global seismicity and stresses have built up. Some of the immediate activity may occur with a geomagnetic storm which is due today as noted in this summary:

 

 

"A minor geomagnetic storm is likely during March 31, especially at high latitudes and maximizing near mid-day. This could bring enhanced global seismicity over the next two days near the geomagnetic equator and at high latitudes." (March 30-31, 2019)

 

The strongest earthquake in the world today was an M 6.2 in New Britain. This  may be related to volcanism which occurs in a number of volcanoes near this epicenter. Today's event was not immediately reported felt in this epicentral area. This is the strongest earthquake in the region of New Britain since an M 7.0 on October 10, 2018. Forecast 114488 had expected this event within about 100 km of this epicenter was likely around March 28.

 

O: 30MAR2019 11:20:45   5.6S  151.0E Mw=6.2  EMSC   NEW BRITAIN REGION, P.N.G.   

P: 28MAR2019 114488     6.0S  152.0E 4.0-5.6 AAAAA  New Britain                

 

A moderate earthquake of M 5.2 was widely felt in northern Greece today. NEIC reported this earthquake of M 5.2 in Greece was felt with intensity V in Distomon, Voiotia, Greece and II-III in the area(s) of Parral, Loutra Oraias, Nauplion, Khalkis, Eleusis, Nikaia, Augaleo and Persterion, Attiki, Greece.  This is the strongest earthquake in Greece since an M 5.4 about 200 km to the  west occurred on February 5, 2019. Forecast 114575 had expected today's activity within about 100 km of this epicenter in Northern Greece was likely around March 29.

 

O: 30MAR2019 10:46:19  38.3N   22.3E Mw=5.2  EMSC   GREECE                       

P: 29MAR2019 114575    39.0N   21.0E 3.0-4.9 AAAAA  No. Greece                 

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the Near Islands, Aleutians. It was not reported felt in this remote area. The last earthquake in the area of M>=4.2 was an M 4.4 on March 16, 2019 and prior to that an M 4.2 on March 1, 2019. Forecast 114670 had expected today's activity was likely around March 31.

 

O: 30MAR2019 09:05:03  51.3N  171.3E mb=4.2  EMSC   NEAR ISLANDS, ALEUTIAN ISLANDS

P: 31MAR2019 114670    53.0N  170.0E 4.0-5.6 ABAAA  Near Islands               

 

VOLCANIC CENTERS ACTIVE   

 

EARTHQUAKE SUMMARY FOR MARCH 29, 2019

 

Popocatepl Volcano in Central Mexico erupted today. Ash was sent up to 8200 feet

and a spectacular lava flow occurred. This appears to be part of a general increase in global volcanism today. Hawaii also appeared to be returning to a more active condition especially in the Kilauea region. The strongest earthquake in the world - an M 5.9 in the South Indian Ridge - also occurred at a volcanic center. This is near the antipode to Central Mexico.  This may be related to a minor increase in geomagnetic disturbances which has occurred over the past two days. Seismic activity in central Mexico had been expected today within about 100 km of forecast 114525.

 

O: 29MAR2019 08:59:18  16.8N   99.5W ML=4.0  EMSC   GUERRERO, MEXICO             

P: 29MAR2019 114525    16.0N  100.0W 3.5-5.3 AAAAA  Oaxaca, Mexico             

 

The earthquake of M 5.9 in the Mid-Indian Ridge occurred about 8 minutes after the event in northern Hawaii. This is not sufficient time for seismic waves to make the 140 degree journey from one to the other, but external effects from geomagnetic disturbances could have helped promote both events. The earthquake in the Mid-Indian Ridge occurred near local solar noon and may also have been promoted by tidal effects which maximize at this hour. Forecast 114709 had expected enhanced activity in this region in late March. Part of this was due to the presence of Tropical Cyclone Joaninha as noted in previous issues of this  ummary:

 

"Tropical cyclone Joaninha (22S) continued in the South Indian Ocean today with winds up to 70 kts. This system could enable further seismicity the the South Indian Ocean seafloor and ridges." (March 23-27, 2019)

 

This is the strongest earthquake in the Mid-Indian Ridge within about 250 km of this epicenter since an M 5.9 on December 2, 1998. Only two other such quakes have occurred in the area in the past 30 years - an M 6.1 on March 22, 1990 and an M 5.9 on February 22, 1990. This epicenter is at 103 degrees from the M 7.3 Komandorsky Island earthquake of December 20, 2018 and may have been promoted from that source.

 

O: 30MAR2019 06:27:23   9.7S   66.5E Mw=5.9  EMSC   MID-INDIAN RIDGE             

O: 30MAR2019 06:27:23   9.7S   66.5E mw=5.9  ANSS   Mid-Indian Ridge"

P: 22MAR2019 114709    14.0S   66.0E 4.0-5.5 CCAAA  So. Indian Ocean           

 

The strongest earthquake in the U.S. or Canada today was an M 3.5 in Hawaii. It was felt widely in the northern portion of the island of Hawaii. NEIC reported maximum intensity IV in Paauilo and II-III in Hawaii at Kapaau, Hawi, Honokaa, Waikoloa, Kamuela, Ookala, Laupanoehoe, Papaaloa and Hakalau. This is the strongest earthquake within about 50 km of this epicenter in Hawaii since an M 3.6 on October 23, 2018. The area saw a number of events of M 3.5-4.5 during the Hawaii eruptions last summer. Forecast 114535 had expected today's event was likely in this area around March 28.

 

O: 30MAR2019 06:29:29  20.2N  155.8W Ml=3.5  EMSC   HAWAII REGION, HAWAII        

P: 28MAR2019 114535    20.4N  155.1W 4.0-5.5 AAAAA  Hawaii area                

 

STRONG EARTHQUAKE EAST OF KURIL ISLANDS

 

EARTHQUAKE SUMMARY FOR MARCH 28, 2019

 

The strongest earthquake in the world today was an M 6.1-6.2 in the Northern Kuril Islands. NEIC reported it was felt with intensity IV in Jelizovo, Kamchatka and III in Petropavlovsk Kanchatka, Russia. This is a somewhat unusual epicenter for large earthquakes and may be an outer rise event. Outer Rise earthquakes can signal regional stresses which can lead to a stronger upcoming quake down the subducting plate. The last earthquake in this region east of the Kuril Islands within about 200 km of this epicenter was an M 7.0 on March 8, 1999. An M 6.3 occurred about 200 km north of this on July 30, 2010. The last such event within about 150 km  of today's epicenter occurred in June 1996 as a series beginning with an M 7.0 on June 21, 1996. The only other such event in the region in the past 30 years was an M 7.0 on November 13, 1993. Forecast 115668 had expected strong regional seismicity to the north of this around March 29.

 

O: 28MAR2019 23:19:39  50.5N  159.8E mb=4.1  EMSC   EAST OF KURIL ISLANDS

O: 28MAR2019 22:16:49  50.5N  159.8E mb=4.4  EMSC   EAST OF KURIL ISLANDS

O: 28MAR2019 22:06:49  50.5N  159.9E Mw=6.1  EMSC   EAST OF KURIL ISLANDS

O: 28MAR2019 22:06:49  50.5N  160.0E mw=6.2  ANSS   ESE of Ozernovskiy Russia

O: 29MAR2019 01:29:35  50.5N  159.9E mb=4.3  EMSC   EAST OF KURIL ISLANDS        

P: 29MAR2019 114668    53.0N  158.0E 4.0-5.9 ACBAA  Kamchatka                  

 

An earthquake of M 5.4 in the Antofagasta area of northern Chile also occurred today. No damage or casualties were immediately reported with this event.

CSN reported this earthquake was felt with intensity V in Antofagasta at Antofagasta and Mejillones; IV in Maria Elena, Taltal and II in Baquedano and Sierra Gorda; Atacama with IV in Chanaral, Diego de Almagro and III in Caldera, Copiapo and Tierra Amarilla, Chile. NEIC reported this earthquake of M 5.4 in northern Chile was felt with intensity II-III in the area(s) of Antofagasta, Chile at Taltal and Calama, Chile. The last earthquake within about 150 km of this epicenter with M>=5.4 occurred December 28, 2017 with M 5.5 and prior to that an M 6.2 on November 27, 2015. Forecast 114723 expected a moderately strong earthquake was possible within  about 100 km of this epicenter around March 24.

 

O: 28MAR2019 15:05:32  24.6S   70.1W Mw=5.4  EMSC   ANTOFAGASTA, CHILE           

O: 28MAR2019 15:05:32  24.5S   70.1W mw=5.4  ANSS   NNE of Taltal Chile

O: 28MAR2019 21:00:50  24.8S   71.0W mb=4.2  EMSC   OFFSHORE ANTOFAGASTA, CHILE  

O: 28MAR2019 15:05     24.6S   70.1W mb=5.4  GUC    Antofagasta at Antofagasta and

P: 24MAR2019 114723    24.0S   69.0W 4.0-5.6 BAAAA  Coast No. Chile            

 

A moderate M 4.2 occurred today off the coast of Northern California. NEIC reported it was felt with intensity IV in Ferndale and Petrolia, California and II-III within about 50 km of the epicenter at Rio Dell, Loleta, Fortuna, Hydesville, Scotia, Eureka, Carlotta, California. This is the largest earthquake within about 50 km of this epicenter since an M 4.4 on February 6, 2019 and prior to that an M 4.5 on February 2 and 3, 2019. This follows nearly a year of quiet in the region after an M 4.7 on March 23, 2018.  Several earthquakes of M>=4 have occurred to the west of this in the past week and a larger regional event is possible in this activation cycle.  Forecast 114639 had expected today's event within about 25 km of the epicenter was likely around March 29.

 

O: 29MAR2019 04:55:26  40.4N  124.4W Mw=4.2  EMSC   OFFSHORE NORTHERN CALIFORNIA 

P: 29MAR2019 114639    40.3N  124.7W 2.5-4.6 AAAAA  Off Coast of No. Calif     

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Andreanof Islands, Aleutians, Alaska. It was not reported felt in this active region. The last earthquake within about 150 km of this epicenter with M>=4.8 occurred as an M 5.2 about 150 km to the west on March 11, 2019. The last within about 100 km of today's epicenter was an M 5.0 on February 15, 2019. Forecast 114660 had expected today's event was likely within about 50 km around March 29.

 

O: 29MAR2019 05:13:55  51.5N  176.2W mb=4.8  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 29MAR2019 114660    51.9N  176.0W 3.5-4.9 AAAAA  Andreanoff Isls, Aleutians 

 

UNUSUAL QUAKE ON XINJIANG-QINGHAI BORDER, CHINA

 

EARTHQUAKE SUMMARY FOR MARCH 27, 2019

 

The strongest earthquake recorded in the world today was an M 5.2 along the Xinjiang-Qinghai Border region of China. It was followed by aftershoks of M 4.2 and 4.5 in the next 1.5 hours. While none of these events were immediately reported felt or damaging, information is not normally available for earthquakes in this region until several days have passed and it is likely these events were felt with moderate intensity in the epicentral area. The M 5.2 is the strongest event within about 200 km of today's epicenters since an M 6.4 on February 11, 2013. The strongest event in the area in the past 30 years was an M 6.1 on October 2, 1993.  Forecast 114612 had expected moderate activity in the Xizang, China area was likely to the southeast of this around March 28.

 

O: 27MAR2019 23:00:22  38.3N   90.8E mb=4.5  EMSC   XINJIANG-QINGHAI BDR REG, CHIN

O: 27MAR2019 22:57:09  38.4N   90.9E mb=4.2  EMSC   XINJIANG-QINGHAI BDR REG, CHIN

O: 27MAR2019 21:36:33  38.4N   90.9E mb=5.2  EMSC   XINJIANG-QINGHAI BDR REG, CHIN

P: 28MAR2019 114612    36.0N   93.0E 3.8-5.2 ACBAA  Xizang                     

 

The strongest seismicity in the U.S. or Canada today continued in the northern  Alaska aftershock zone where an unusual M 5.2 occurred yesterday. The largest of today's aftershocks was an M 4.6, but was not reported felt in this remote area.

 

The only other such event in about 200 km of this epicenter with M>=5.2 in the past 30 years was an M 5.2 on March 6, 2019.  Forecast 114692 expected today's event was likely around March 26 in the aftershock zone.

 

O: 27MAR2019 17:12:12  66.3N  157.0W ML=3.0  EMSC   NORTHERN ALASKA

O: 27MAR2019 10:56:07  66.3N  157.0W ML=3.6  EMSC   NORTHERN ALASKA

O: 27MAR2019 13:06:51  66.3N  157.1W ML=3.8  EMSC   NORTHERN ALASKA

O: 27MAR2019 19:55:25  66.3N  157.2W ML=3.1  EMSC   NORTHERN ALASKA

O: 27MAR2019 18:22:56  66.3N  157.4W ML=3.9  EMSC   NORTHERN ALASKA

O: 28MAR2019 04:22:23  66.3N  157.5W ml=3.0  EMSC   NORTHERN ALASKA

O: 28MAR2019 06:52:02  66.3N  157.6W ML=3.2  EMSC   NORTHERN ALASKA

O: 28MAR2019 06:15:41  66.3N  157.6W ML=3.4  EMSC   NORTHERN ALASKA

O: 27MAR2019 07:38:37  66.4N  157.6W mb=4.6  EMSC   NORTHERN ALASKA              

P: 26MAR2019 114693    66.0N  155.0W 3.0-5.1 AAAAA  Northern Alaska            

 

MODERATELY STRONG QUAKE SHAKES EL SALVADOR

 

EARTHQUAKE SUMMARY FOR MARCH 26, 2019

 

The strongest earthquake in the world today was an M 5.6 off the southern coast of El Salvador. NEIC reported it was felt strongly with intensity VII in San Luis la Harradura, La Paz, El Salvador and with II in Antigua Cscatlan, El Salvador and Ciudad Sandino, Nicaragua. This continues activation of this region which began several days ago and has been covered in several previous issues of this summary. The M 5.6 was followed by a strong aftershock sequence which included M 4.8 and 4.9 events.  The last earthquake in El Salvador within about 150 km of today's epicenter  with M>=5.6 occurred off Guatemala as an M 6.1 on October 28, 2018. The last off southern El Salvador was an M 6.1 on June 10, 2016. Forecasts 114226 and 114509 had expected this area would be active within about 50 km  of these epicenters between March 19 and 29. This summary noted this active period first on March 25 as:

 

"The strongest earthquake in the world today was an M 5.3 in Nicaragua. This joined a series of moderate earthquakes from Oaxaca, Mexico (M 5.1) to Costa Rica (M 4.3)." (March 24-25, 2019).

 

O: 26MAR2019 19:07:30  12.5N   89.2W mb=4.7  EMSC   OFFSHORE EL SALVADOR

O: 26MAR2019 15:01:44  12.5N   89.3W mb=4.9  EMSC   OFFSHORE EL SALVADOR

O: 26MAR2019 15:26:54  12.6N   89.0W mb=4.8  EMSC   OFFSHORE EL SALVADOR

O: 26MAR2019 12:01:52  12.6N   89.2W Mw=5.6  EMSC   OFFSHORE EL SALVADOR

O: 26MAR2019 12:07:38  12.5N   89.2W ML=4.1  EMSC   OFFSHORE EL SALVADOR         

O: 26MAR2019 12:01:48  12.5N   89.2W mw=5.6  ANSS   La Libertad El Salvador

P: 19MAR2019 114226    13.0N   89.0W 3.5-5.1 CAAAA  Coast of Central America   

P: 29MAR2019 114509    14.0N   89.0W 3.5-5.1 BBAAA  Coast of Central America   

 

A pair of moderate earthquakes also shook the region of southwest Japan in Kyushu and Shikoku today. NEIC reported this earthquake of M 5.4 in Shikoku, Japan was felt with intensity II-III in the area(s) of Miyazaki, Japan at Hyuga, Miyazaki, Miyakonojo, in Oita, at Oita and Beppu and in Hikari Yamaguchi, Hiroshima and Otau, Shiga, Japan. The aftershock of  M 5.3 in Shikoku, Japan was felt with intensity II-III in the area(s) of Miyazaki and Yamaguchi, Japan.

The last earthquake in the region of Shikoku within about 200 km of the M 5.4 today with equal or greater magnitude occurred on April 14-15, 2016 and included an M 7.0 about 200 km northwest of today's epicenter. More recent activity, including and M 6.3 on January 8, 2019 has occurred about 250 km to the southwest of today's epicenter. Forecast 114570 had expected today's activity within about 100 km was likely around March 22.

 

O: 27MAR2019 06:38:06  32.2N  132.0E Mw=5.3  EMSC   KYUSHU, JAPAN                

O: 27MAR2019 00:11:25  32.2N  132.0E Mw=5.4  EMSC   SHIKOKU, JAPAN               

P: 22MAR2019 114570    31.0N  132.0E 3.5-5.3 BBAAA  Kyushu, Japan area         

 

The strongest earthquake in the U.S. or Canada today was an M 5.2 in Northern Alaska. NEIC reported it was felt lightly with intensity II in Alaska at Huslia, Noorvik, Nulato. This is an aftershock of the series which began with an M 5.3 on October 14, 2018. The only other such event in about 200 km of this epicenter with M>=5.2 in the past 30 years was an M 5.2 on March 6, 2019.  Forecast 114692 expected today's event was likely around March 26 in the aftershock zone. The mainshock occurred within about an hour of local solar noon and may have been promoted by tidal effects which maximize at this hour. When the M 5.2 occurred on March 6, this summary noted it as:

 

"The strongest earthquake in the U.S. or Canada today was an M 5.2 in northern Alaska. NEIC reported it was felt with intensity II-III in Shungnak and Hualia, Alaska. This is part of a series which has been occurring near this epicenter since late 2018. It is the strongest earthquake within about 200 km of this epicenter since an M 5.3 on October 14, 2018, the only other such event in the area in  at least 30 years." (March 6, 2019)

 

This activity is at 102 degrees from the M 7.0 in Peru of March 1, the last major earthquake in the world and may have been promoted from that event. Seismic energy concentrates on the surface at this distance after major earthquakes and probably helps trigger enhanced seismicity.

 

O: 26MAR2019 21:35:31  66.3N  156.9W ml=3.8  EMSC   NORTHERN ALASKA

O: 27MAR2019 01:07:07  66.3N  157.0W ML=3.5  EMSC   NORTHERN ALASKA

O: 26MAR2019 21:27:20  66.3N  157.2W Mw=5.0  EMSC   NORTHERN ALASKA

O: 26MAR2019 21:27:17  66.3N  157.2W ml=5.2  ANSS   Northern Alaska

O: 26MAR2019 21:56:34  66.3N  157.2W ml=3.3  EMSC   NORTHERN ALASKA

O: 26MAR2019 22:30:16  66.3N  157.5W ML=3.1  EMSC   NORTHERN ALASKA

O: 27MAR2019 05:06:35  66.3N  156.9W ml=3.7  EMSC   NORTHERN ALASKA              

P: 26MAR2019 114693    66.0N  155.0W 3.0-5.1 AAAAA  Northern Alaska            

 

WESTERN AMERICAS REMAIN ACTIVE

 

EARTHQUAKE SUMMARY FOR MARCH 25, 2019

 

Moderate seismicity continued from Central America to northern Chile today. The strongest earthquake of the day was another M 5.2 in the Tarapaca, Iquique region of Northern Chile. The only other event within about 150 km of today's epicenter with M>=5.2 during 2019 was an M 5.3 on February 6, 2019. Both may be regional aftershocks of a strong M 6.2 of November 1, 2018, the largest in the area since an M 7.6 on April 3, 2014. CSN reported this earthquake was felt with intensity IV in Tarapaca at Alto Hospicio, Iquique, Pozo Almonte V in El Loa and III in Huara, La Tirana, Pica, Pisagua and in Antofagasta with IV in Quillagua and III in Maria Elena and Tocopilla, Chile. NEIC reported this earthquake of M 5.2 in Northern Chile was felt with intensity II-III in the area(s) of Iquique, Tarapaca and Calama, Antofagasta, Chile. Forecast 114723 expected today's activity was likely within about 100 km of this epicenter around March 26.

 

O: 25MAR2019 10:52:39  21.4S   70.0W mb=5.2  EMSC   TARAPACA, CHILE              

O: 25MAR2019 10:52     21.3S   70.1W mb=4.9  GUC    Tarapaca at Alto Hospicio, Iqu

P: 26MAR2019 114723    22.0S   69.0W 4.0-5.4 AAAAA  Coast No. Chile            

 

The most unusual earthquake in the U.S. or Canada today was an M 2.2 in eastern North Carolina. NEIC reported it was felt with intensity II-III within about 50 km of the epicenter in North Carolina at Sylva, Franklin, Whittier, Cullowhee, Highlands, Tuckasegee, Otto, Bryson, Waynesville, Cherokee, High Point, Jamestown, Greensboro, Pleasant Garden, Randleman, Sophia, North Carolina. The last earthquake in North Carolina within about 100 km of this epicenter with M>=2.2 occurred on November 15, 2016 with M 2.6. Most activity in the area occurs in the Appalachians about 150 km to the west of today's epicenter.   The only comparable event east of 80 West longitude in the past 30 years was an M 2.7 on July 12, 1993. Forecast 114600 had expected today's event to the south in South Carolina was likely around March 24.

 

 

O: 26MAR2019 04:32:30  35.9N   79.9W mb=2.2  EMSC   NORTH CAROLINA               

P: 24MAR2019 114600    33.0N   80.0W 2.0-4.1 ACAAA  Southeast U.S.             

 

CENTRAL AMERICA ACTIVE

 

EARTHQUAKE SUMMARY FOR MARCH 24, 2019

 

The strongest earthquake in the world today was an M 5.3 in Nicaragua. This joined a series of moderate earthquakes from Oaxaca, Mexico (M 5.1) to Costa Rica (M 4.3). NEIC reported this earthquake of M 5.3 in Nicaragua was felt with intensity IV in Nicaragua at La Paz,  Ciudad Sandino, San Rafael del Sur, Managua, El Crucro, Mamagua, Dinamba, Ticuantepe and San Marcos and II-III in the area(s) of Nicaragua at Nagarote, Leon and San Marcos.  An aftershock of  M 4.5 in Nicaragua was felt with intensity IV in the area(s) of Managua, Nicaragua. The event in Nicaragua is the strongest within about 150 km of today's epicenter since an M 5.3 on January 15, 2019. The last of significantly larger magnitude in this area was an M 5.6 on May 6, 2018.  Forecast 114521 had expected today's event in Nicaragua within about 100 km  was likely around March 27.

 

O: 24MAR2019 09:30:02  12.1N   86.7W Mw=5.3  EMSC   NICARAGUA                    

O: 24MAR2019 16:19:47  12.4N   86.8W mb=4.5  EMSC   NICARAGUA                    

P: 27MAR2019 114521    12.0N   86.0W 3.5-5.1 BAAAA  Nicaragua                  

 

Among others, the largest quake in Mexico today was an M 5.1 off the southern

Coast of Oaxaca.  NEIC reported this earthquake of M 5.1 in Oaxaca, Mexico was felt with intensity II-III in the area(s) of Guichicovi, Oaxaca; Acapulco, Guerrero and Tlainepantla, Mexico. Two earthquakes of M>=5.1 have hit the region within about 200 km of this epicenter in the past half year - an M 5.4 in Chiapas on March 5, 2019 and an M 5.8 within about 25 km of today's epicenter on January 21, 2019. Forecast 114500 had expected today's event was likely around March 26 within about 100 km of today's epicenter.

 

O: 25MAR2019 06:47:32  15.2N   94.6W ML=4.2  EMSC   OFF COAST OF OAXACA, MEXICO  

O: 24MAR2019 10:57:40  15.3N   94.8W ML=4.0  EMSC   OFF COAST OF OAXACA, MEXICO  

O: 24MAR2019 12:27:36  15.6N   94.8W Mw=5.1  EMSC   OFFSHORE OAXACA, MEXICO      

P: 27MAR2019 114508    16.0N   94.0W 3.5-5.3 BAAAA  Chiapas, Mexico            

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote area. iThe last event of M>=4.8 within  about 150 km of this epicenter occurred February 18, 2019 with M 4.8 and prior to that on March 19, 2018 also with M 4.8. Forecast 114674 had expected today's event in the Rat Islands was likely around March 23.

 

O: 24MAR2019 21:17:41  51.9N  178.5E mb=4.8  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 23MAR2019 114674    52.0N  177.0E 4.0-5.9 AAAAA  Rat Islands                

 

The strongest earthquake in the U.S. or Canada outside Alaska today was an M 4.4 in the region off the coast of Northern California. NEIC reported it was felt with intensity II along the coast at Eureka, McKinleyville, and possibly in San Francisco, California and in Oregon at Klamath Falls. This is the strongest earthquake within about 75 km of this epicenter west of 124.5 West longitude since an M 4.5 on July 25, 2018 and prior to that an M 4.5 on May 7, 2018. The last in the area of larger magnitude than M 4.4-4.5 was an M 4.7 a year ago on March 23, 2018.  Forecast 114639 had expected this activity within about 25 km was likely around March 23.

 

O: 24MAR2019 11:32:01  40.4N  125.1W Mw=4.4  EMSC   OFFSHORE NORTHERN CALIFORNIA 

P: 23MAR2019 114639    40.6N  124.9W 2.5-4.6 AAAAA  Off Coast of No. Calif     

 

The most unusual earthquake in the U.S. today was an M 2.7 in the area of western Florida in the Panhandle region. Earthquakes in Florida are rare but this appears to be an aftershock of events of M 3.1 on March 11, 2019 and M 2.7 on March 7, 2019, the first in the area within about 200 km of this epicenter since 2011. When  the mainshocks occurred in early March this summary noted them as:

 

"The most unusual earthquake in the U.S. today was an M 3.1 in southern Alabama. NEIC reported this earthquake of M 3.1 in Alabama was felt with intensity II-III in the area(s) of Century, Pensacola and Jay, Florida and in Mobile, Atmore and Brewton, Alabama.  Florida seldom feels tremor from earthquakes, so this is a significant regional event. The last earthquake within about 200 km of this epicenter with M>=3.1 occurred on February 18, 2011 and prior to that an M 3.1 on May 16, 2008." (March 12, 2019)

 

Forecast 114599 had expected an aftershock within about 25 km of today's epicenter was likely around March 22.  NEIC reported this earthquake of M 2.7 in Western Florida was felt with intensity II-III in the area(s) of Flomaton, Alabama.

 

O: 24MAR2019 11:39:57  31.0N   87.2W mb=2.7  EMSC   WESTERN FLORIDA              

P: 22MAR2019 114599    31.0N   87.0W 2.0-4.1 AAAAA  Southeast U.S.             

 

STRONG QUAKES NEAR THE EQUATOR IN COLOMBIA AND MOLUCCA SEA

 

EARTHQUAKE SUMMARY FOR MARCH 23, 2019

 

The most widely felt and strongest earthquake in the world today occurred in west-Central Colombia. NEIC reported it was felt with maximum intensity VI in Ansermanuevo, Valle del Cauca, Colombia and V i El Cairo, and Montenegro, Colombia. Intensity IV was felt within about 150 km of the epicenter in Colombia at Santuarjo, Armenia, Tulua, Sevilla, Cartago, and Roldanillo in Valle del Cauca and in Versailes, Colombia with intensity III. This is the strongest earthquake in Colombia within about 200 km of today's epicenter since an M 7.2 on November 15, 2004. Ten earthquakes of M>=6.1 hit the region between 1990 and 2007 within about 250 km of today's epicenter, the last was an M 6.8 on September 10, 2007 about 250 km southwest of today's event but no such quakes have occurred since then.  Forecasts 114470 and 114180 had expected this event in mid-March within about 50 km  of today's epicenter. Seismicity near the geomagnetic equator had been expected to be enhanced at this time as noted in previous issues of this summary:

 

"The most likely time for such (geomagnetic) promotion is March 25-28. A major geomagnetic storm is due March 23-24. This could bring strong seismicity with it  especially near the geomagnetic equator or sub-solar events at the time of the storm initiation." (March 22-23, 2019)

 

Today's event in Colombia is located at 102 degrees from the M 7.3 in the Komandorsky area of December 20, 2011, a distance at which triggering is considered likely and may have been promoted by energy from that event.

 

O: 23MAR2019 19:21:15   4.6N   76.3W Mw=6.1  EMSC   COLOMBIA                     

O: 23MAR2019 19:21:16   4.6N   76.3W mw=6.1  ANSS   El Dovio Colombia

P: 12MAR2019 114188     5.0N   76.0W 4.0-5.4 CAAAA  Colombia                   

P: 23MAR2019 114470     7.0N   78.0W 4.0-5.4 ACNAA  Colombia                   

 

A strong M 6.1 also occurred today in the Molucca Sea of central Indonesia. NEIC reported it was felt with intensity III in Manado, Sulawesi, Indonesia. This was part of an activation of the region of Indonesia which included this as well as an M 5.4-5.7 in Sulawesi and two events in the Andaman Islands of M 5.2 and 5.3.  BMG reported the M 6.3 was felt with intensity III-IV in Manado, Tondano, Bitung; III in Weda, Jailoloand Ternate and II-III in Tahuna, Siau and Bolang, Maluku, Indonesia. The last earthquake of M>=6.1 within about 200 km of today's epicenter in the Molucca Sea occurred January 6, 2019 about 100 km northeast of today's epicenter and prior to that an M 6.3 on June 7, 2016. Forecast 114474 had expected today's event within about 50 km was likely around March 22. This event was probably promoted by tidal stresses as it occurred within about an hour of local solar noon, a time when tidal stresses maximize in the earth.

 

O: 24MAR2019 04:37:36   1.7N  126.4E Mw=6.1  EMSC   MOLUCCA SEA                  

O: 24MAR2019 04:37:34   1.7N  126.4E mw=6.1  ANSS   ENE of Bitung Indonesia

O: 24MAR2019 04:37:34  01.7N  126.3E MS=6.3  BMG  Felt with intensity III-IV

P: 22MAR2019 114474     2.0N  126.0E 4.0-5.4 AAAAA  Mindanao, Philippines      

 

BMG reported the M 5.4-5.7 in Sulawesi was felt with intensity IV in Poso, Ampana, Morowali; III-IV in Mangkutana; III in Palu, Soroako, Malili and II-III in Palopo, Sulawesi, Indonesia. NEIC reported this earthquake of M 5.4 in Sulawesi, Indonesia was felt with intensity II-III in the area(s) of Palu, Sulawesi, Indonesia.

 

O: 24MAR2019 01:32:05   1.8S  120.6E Mw=5.4  EMSC   SULAWESI, INDONESIA          

O: 24MAR2019 01:32:02  01.8S  120.5E MS=5.7  BMG  Felt with intensity IV

O: 24MAR2019 01:31:59   1.8S  120.5E mw=5.4  ANSS   NNW of Pendolo Indonesia

P: 30MAR2019 114466     1.0N  120.0E 4.0-5.5 CCAAA  Celebes Sea                

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the Anchorage, Alaska aftershock zone. NEIC reported it was felt with intensity II-III in Wasilla, Willow, Elmendorf, Fort Richardson, Anchorage, Chugiak and within about 50 km of the epicenter.  This area has been active since the M 7.0 mainshock of November 30, 2018. The last event of M>=4.2 in the aftershock sequence was an 4.4 more than a month ago on February 18, 2019. Seven such aftershocks hit the region with M>=4.2 in January and February, 2019. The largest were of M 5.0 on January 1 and January 13, 2019.  Forecast 114686 had expected a moderate aftershock in the area around March 23.

 

O: 23MAR2019 15:14:44  61.4N  149.9W mb=4.2  EMSC   SOUTHERN ALASKA               

P: 23MAR2019 114686    60.9N  151.1W 3.2-4.9 AAAAA  Central Alaska             

 

A moderately larger M 5.1-5.4 earthquake also occurred in the Central Mid-Atlantic Ridge today. It was not reported felt in this remote area. It may be related to antipodal effects of Tropical Cyclone Trevor which passed over the antipode to this event several days ago. This summary expected some enhanced activity near today's North Atlantic event as:

 

"The antipode (of TC Trevor) is on the Central Mid-Atlantic at 12N 35W, an active region where a moderate earthquake is possible should this system intensify." (March 18-20, 2019)

 

It is also possible that this event which occurred near local solar noon was enhanced by tidal stresses as it lies in the longitude band of highest stresses associated with the full moon of March 21. This forecast has noted in previous issues:

 

 

"The full moon will arrive at 01:43 UT on March 21. Longitudes which area sub-lunar at this time are near 26 West and sub-solar at 154 East. These include the mid-Atlantic Ridge where a series of moderate earthquakes is occurring in the Azores, the South Sandwich Islands, and the region of Kamchatka and New Guinea among others. These will experience maximum tidal stresses but many areas are subject to tidal triggering outside these longitude zones. A strong tidal-related earthquake is likely in the next seven days. Tidally promoted events often occur with geomagnetic storms and/or near local solar noon or midnight." (March 18-23, 2019)

 

The last event of M>=5.4 within about 200 km of today's epicenter was an M 5.8 on October 7, 2018 and prior to that an M 5.5 on May 23, 2018 and an M 5.5 on August 16, 2012. Forecast 114467 had expected today's event within about 100 km was likely around March 24.

 

O: 23MAR2019 12:35:28   7.5N   37.2W mb=5.1  EMSC   CENTRAL MID-ATLANTIC RIDGE   

O: 23MAR2019 12:35:24   7.5N   37.1W mw=5.4  ANSS   Central Mid-Atlantic Ridge"

P: 24MAR2019 114467     8.0N   38.0W 4.0-5.5 AAAAA  Central Mid-Atlantic Ridg  

 

SOLOMON ISLANDS ACTIVE; GEOMAGNETIC STORM LIKELY

 

EARTHQUAKE SUMMARY FOR MARCH 22, 2019

 

The strongest earthquake in the world today was an M 5.4 in the southeastern Solomon Islands. It lies near the geomagnetic equator and mayhave been promoted by geomagnetic effects from the oncoming storm. This summary expects that storm will occur today with some aurora borealis and other electrical effects. These can induce currents in the earth and help trigger seismicity beneath ionospheric ring currents near the geomagnetic equator and at high latitudes. The geomagnetic effects on seismicity are anticipated as:

 

Today's geomagnetic storm "may help to promote seismicity near the geomagnetic equator and at high latitudes. The most likely time for such promotion is March 23 and March 25-28. A major geomagnetic storm is due March 23. This could bring strong seismicity with it  especially near the geomagnetic equator or sub-solar events at the time of the storm initiation." (March 21-23, 2019)

 

The M 5.4 in the Solomon Islands is the strongest within about 150 km of that epicenter since an M 6.2 about 100 km to the northeast occurred on November 16, 2018. Forecast 114715 had expected this event within about 50 km of the epicenter was likely around March 24.

 

 

O: 22MAR2019 14:52:57  11.4S  162.6E Mw=5.4  EMSC   SOLOMON ISLANDS              

P: 24MAR2019 114715    11.0S  163.0E 4.0-5.4 AAAAA  Vanuatu Islands            

 

The strongest earthquake in the U.S. or Canada today was an M 4.9 in the western Andreanof Islands, Aleutians, Alaska. It was not reported felt in this remote area. The last earthquake of M>=4.9  within about 150 km of this epicenter was an M 5.2 on March 11, 2019. An M 5.9  occurred in this epicentral area on January 5, 2019. These are probably aftershocks of that event. Forecast 114662 had expected this activity was likely around March 23.

 

O: 22MAR2019 20:25:04  51.4N  178.3W mb=4.9  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 23MAR2019 114662    51.2N  179.9W 3.5-4.9 AAAAA  Andreanoff Isls, Aleutians 

 

UNUSUAL EARTHQUAKES ACCOMPANY FULL MOON

 

EARTHQUAKE SUMMARY FOR MARCH 21, 2019

 

Unusual earthquakes occurred today in East and Southern Africa following an increase in solar flare activity. An M 5.5 in Tanzania was felt in Tanzania, Rwanda, Zambia and Malawi while an M 4.9 shook several Free States in South Africa. The solar flare activity today included a C5.6, the strongest flare registered this year. Following are parameters for this event which was one of several C-class flares today.

 

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

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

 

8880       0308   0312      0315   C5.6      (March 21, 2019)   1.2E-03  

 

The largest earthquake in the world today was an M 5.5 in the area of Tanzania, Africa. NEIC reported maximum intensity V in Libala, northern Zambia and IV in Tanzania at Laela Rukwa, Mbeya, Kiwira, Tanzania and II-III in Tanzania in Makungu, Chimala, and Sumbawanga Rukwa; in Zambia at Mungwi and at Mzuzu, Malawi and Kigali Ville de Kigali, Rwanda. This earthquake occurred near the time of the full moon and was probably promoted by tidal stresses. This event occurred within about an hour of local solar noon a time when tidal stresses maximize in the earth. The last earthquake of M>=5.5 within about 200 km of this epicenter occurred as an M 5.5 on February 20, 2002 also with M 5.5. An M 6.5 hit the area on October 2, 2000. The last event within about 250 km of today's epicenter was an M 5.9 in Malayi on February 24, 2017 about 250 km to the southwest and prior to that an M 5.5 on November 14, 2009 about 250 km to the northwest. Forecast 114205 had expected today's activity was likely around March 21 about 260 km to the northwest of today's epicenter.

 

O: 21MAR2019 09:15:38   7.9S   32.1E mb=5.1  EMSC   LAKE RUKWA REGION, TANZANIA  

O: 21MAR2019 09:15:40   7.9S   32.1E mw=5.5  ANSS   E of Sumbawanga Tanzania

P: 21MAR2019 114205     6.0S   30.0E 3.0-4.5 ABBAA  Lake Victoria area         

 

An unusually large earthquake of M 4.9 shook South Africa today. NEIC reported it was felt with intensity IV in Virginia Free State and in Welkom Free State, South Africa. The last earthquake within about 150 km of this epicenter with M>=4.9 occurred on April 3, 2017 (M 5.2) and  prior to that an M 5.3 on August 5, 2014.  Forecasts 114434 and 114726 had expected this activity in mid- to late March within about 100 km of this epicenter. This epicenter is located at 101 degrees from the M 7.5 in Ecuador of February 22 and may have been promoted from that source.

 

O: 22MAR2019 00:30:30  28.1S   26.8E mb=4.9  EMSC   SOUTH AFRICA                 

P: 13MAR2019 114434    27.0S   27.0E 3.0-4.7 CBAAA  Rep. South Africa          

P: 31MAR2019 114726    26.0S   28.0E 3.0-4.6 CBAAA  Rep. South Africa          

 

Tidal stresses from the full moon of March 21 also appear to have promoted seismicity today. The most obvious of these was an M 5.2 in the Northern Mid-Atlantic Ridge at 28 West longitude. This event occurred within about an hour of the full moon and was sub-lunar at the time of the full moon an hour earlier. The tidal forecast for this full moon as published in previous issues of this summary had read:

 

"The full moon will arrive at 01:43 UT on March 21. Longitudes which area sub-lunar at this time are near 26 West and sub-solar at 154 East. These include the mid-Atlantic Ridge where a series of moderate earthquakes is occurring in the Azores, the South Sandwich Islands, and the region of Kamchatka and New Guinea among others. These will experience maximum tidal stresses but many areas are subject to tidal triggering outside these longitude zones. A strong tidal-related earthquake is likely in the next seven days. Tidally promoted events often occur with geomagnetic storms and/or near local solar noon or midnight." (March 19-21, 2019)

 

Today's North Atlantic event did not occur at an epicenter which has been active in the recent seismicity of the area. It was probably triggered by strong tidal stresses associated with the full moon. The last event within about 200 km of this epicenter with M>=4.9 occurred August 14, 2017 with M 5.1. The last of M>5.2 in the area was an M 5.4 on September 30, 2013, The only event in the past 30 years of significantly larger magnitude in the area was an M 5.7 on May 17, 2002.  Forecast 114381 had expected today's event within about 50 km of this epicenter was likely around March 16.

 

O: 22MAR2019 02:42:41  49.7N   28.6W mb=4.9  EMSC   NORTHERN MID-ATLANTIC RIDGE  

O: 22MAR2019 02:42:42  49.7N   28.5W mb=5.2  ANSS   NORTHERN MID-ATLANTIC RIDGE  

P: 16MAR2019 114381    50.0N   29.0W 4.0-5.7 CAAAA  North Mid-Atlantic Ridge   

 

The strongest earthquakes in the U.S. or Canada today occurred as an M 4.3 and 4.5-4.6 in the Northwest Territories of Canada. The aftershock of M 4.0-4.3 occurred within minutes of local solar noon and was probably promoted by tidal effects. The last event within about 200 km of today's epicenters with M>=4.6 occurred December 22, 2017 about 200 km southwest of today's events and prior to that as an M 5.5 on March 5, 2006.  No such earthquakes of M>=4.6 have occurred within 150 km of today's epicenters in the past 30 years. Forecast 114698 had expected today's activity was likely within about 100 km of these epicenters around March 22.

 

O: 21MAR2019 20:12:30  66.7N  130.4W mb=4.0  EMSC   NORTHWEST TERRITORIES, CANADA

O: 21MAR2019 20:12:30  66.7N  130.5W MB=4.3  ECAN Fort Good Hope, NT  

O: 21MAR2019 16:33:05  66.7N  130.4W MB=4.5  ECAN Fort Good Hope, NT  

O: 21MAR2019 16:33:03  66.7N  130.4W mb=4.6  EMSC   NORTHWEST TERRITORIES, CANADA

P: 22MAR2019 114698    66.0N  130.0W 2.5-4.1 AAAAA  Yukon Territory, Canada    

 

An earthquake of M 4.7 shook the region of Barbuda, Leeward Islands, today. This is the strongest earthquake in the region of Barbuda within about 100 km

of this epicenter since an M M 4.7 on April 17, 2018. The last of larger magnitude was an M 5.2 on February 9, 2018. Forecast 114514 had expected the Leeward Islands would be active around March 27 to the south of today's epicenter. Previous issues of this summary had expected regional seismicity in this area related to it's antipodal location to Tropical Cyclone Veronica north of Australia as:

 

"TC Veronica (21S) continued south of Lombok, Indonesia and north of Australia today with winds up to 150 kts.  It may help promote additional seismicity in the Sumba, Sumbawa, Bali and Lombok areas of Indonesia or at the antipode which is  17N 63W in the Virgin Islands and Puerto Rico region of the Caribbean. A moderate event in this area could be triggered by antipodal energy from Veronica." (March 19-21, 2019)

 

O: 21MAR2019 08:12:59  18.8N   60.4W ML=4.7  EMSC   NE OF BARBUDA, LEEWARD ISLANDS

P: 27MAR2019 114514    16.0N   60.0W 3.0-5.2 CCAAA  Leeward Islands            

 

STRONG EARTHQUAKE FELT IN CENTRAL VANUATU

 

EARTHQUAKE SUMMARY FOR MARCH 20, 2019

 

An earthquake of M 6.3 in Vanuatu today was the strongest event in the world today. It was reported by NEIC to have been felt with intensity V in Vanuatu at Luganville, Sanma. A C4.8 solar flare, the second strongest of the year ( a flare of C5.0 occurred in late January, 2019) , occurred with maximum output

at 11:18 UT. This occurred several hours before the earthquake of M 6.3 in Vanuatu and M 5.0 in France and probably triggered them. A major geomagnetic storm is considered likely on March 23 which could help enhance seismicity near the geomagnetic equator and at high latitudes.

 

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

 

8740       0707   0714      0716   B6.1      (March 20, 2019)   2.6E-04      

8760       1035   1118      1134   C4.8      (March 20, 2019)   6.7E-03  

 

Another factor which probably promoted this event was strong tidal stresses associated with the full moon which arrived today when this epicenter was within about an hour of local solar noon, a prime time for tidal triggering. This summary had noted this possibility in the tidal forecast as:

 

"The full moon will arrive at 01:43 UT on March 21. Longitudes which area sub-lunar at this time are near 26 West and sub-solar at 154 East. These include the mid-Atlantic Ridge where a series of moderate earthquakes is occurring in the Azores, the South Sandwich Islands, and the region of Kamchatka and New Guinea among others. These will experience maximum tidal stresses but many areas are subject to tidal triggering outside these longitude zones. A strong tidal-related earthquake is likely in the next seven days. Tidally promoted events often occur with geomagnetic storms and/or near local solar noon or midnight." (March 19-20, 2019)

 

The last earthquake in Vanuatu within about 200 km of this epicenter with M>=6.2 was an M 6.5 on August 21, 2018 and prior to that an M 6.8 on May 9, 2017.   Forecast 114426 had expected today's earthquake was likely within about 50 km of this epicenter around March 19.

 

O: 20MAR2019 15:24:00  15.6S  167.7E Mw=6.2  EMSC   VANUATU                      

P: 19MAR2019 114426    15.0S  168.0E 4.0-5.6 AAAAA  Vanuatu Islands            

 

An earthquake of M 3.9-5.0 was widely felt in west-central France today. NEIC reported intensity IV in Lisso-du=Potuou, and II-III in Tauriac, Saint-Romain, Bordeaux, La Haillan, Pessac-sur-Dordogne, Saint-Seunn-de-Prats and Poitiers, France. This earthquake coincided with the C3.8 solar flare which began when this epicenter was near sub-solar, a prime time for geomagnetic/solar effects to promote seismicity. This is an unusually large earthquake for France which has a number of smaller events in the Pyrenees area. The last earthquake within about 200 km of today's event with M>=5 occurred as an M 5.2 on April 18, 2005. The only other such earthquake in the area in the past 30 years was an M 5.1 on June 8, 2001. Forecast 114361 expected today's event south of this epicenter around March 20. This event may also have been promoted by strong tides associated with the full moon today. It occurred near local solar noon.

 

O: 20MAR2019 09:56:40  45.4N    0.4W ML=5.0  EMSC   FRANCE                       

P: 20MAR2019 114361    43.0N    1.0W 3.0-5.4 ACAAA  Spain                      

 

The strongest earthquake in the U.S. or Canada today was an M 3.8 in the Fox  Islands, Aleutians, Alaska. This is not uncommon for this area. The last event in the Fox Islands within about 150 km of this epicenter with M>=3.8 was an M 3.8 on March 15, 2019 but the last of larger magnitude was an M 4.7 on March 7, 2019.Four such events have hit the area thus far in 2019. Forecast 114377 had expected the Fox Islands would be active within about 100 km of this epicenter around March 19.

 

O: 20MAR2019 18:31:35  53.4N  165.4W mb=3.8  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P: 19MAR2019 114377    53.7N  167.0W 3.5-5.0 AAAAA  Fox Islands, Aleutians     

 

MODERATELY LARGE QUAKE SHAKES WESTERN TURKEY

 

EARTHQUAKE SUMMARY FOR MARCH 19, 2019

 

A moderately strong earthquake of M 5.7 occurred today in western Turkey. NEIC reported it was felt with intensity V in Denizli, IV in Usak and II-III in Antara, Izmir, Turkey and in Tel Aviv, Israel. There were no immediate reportsof major damage or casualties.  The mainshock of M 5.7 was preceded by a series of light foreshocks including an M 3.5 and followed by aftershocks including an M 4.4 and 4.5. The last earthquake within about 200 km of this epicenter in Turkey with M>=5.7 was an M 6.6 about 200 km to the southwest of this on July 20, 2017 and prior to that an M 6.0 about 100 km southwest on June 10, 2012.

 

This summary has repeatedly noted the seismic potential of this region. For example on July 21, 2017, the date of the last such event it was noted:

 

"A pair of moderate earthquakes hit the region of northwestern Turkey today. They occurred at slightly different epicenters about an hour apart with the second of M 4.9 probably triggered by the first of M 5.0.  … These lie near the projected epicenter of a major upcoming quake in the Istanbul area and may be precursory to such a shortly expected event. As they are separated by nearly 100 km they may mark the ends of such a rupture.  They are the first events of M>=5 within about 100 km of this region since events of M 5.9 on May 19, 2011 in the east and of M 5.2 on April 17, 2003 in the west." (April 22, 2017) 

 

and on May 28:

 

"An earthquake of M 5.0 and aftershock of M 4.9 were also widely felt in the region south of Istanbul, Turkey on the Anatolian Fault zone. A large earthquake in this area is widely anticipated." (May 28, 2017)

 

The earthquakes of April 22 and 23 occurred on the 25th and 26th day of the lunar month, as did today's activity. This is two days before the new moon in  both cases and probably is a tidally driven earthquake promotion mechanism in the region." (July 11, 2017)

 

Also note that these previous earthquakes were associated with new and full moons. The full moon will arrive tomorrow as noted in previous issues of this summary and probably helped promote today's events. The foreshock activity today began near local solar midnight.

 

"The full moon will arrive at 01:43 UT on March 21. Longitudes which area sub-lunar at this time are near 26 West and sub-solar at 154 East. These include the mid-Atlantic Ridge where a series of moderate earthquakes is occurring in the Azores, the South Sandwich Islands, and the region of Kamchatka and New Guinea among others. These will experience maximum tidal stresses but many areas are subject to tidal triggering outside these longitude zones. A strong tidal-related earthquake is likely in the next seven days. Tidally promoted events often occur with geomagnetic storms and/or near local solar noon or midnight." (March 18-20, 2019)

 

Forecast 114318 had expected today's event was likely within about 50-75 km of the epicenter around March 21 with magnitude up to M 5.4. Another promotional factor in the timing of this event is probably that it lies at 104 degrees distance from the M 7.5 in Ecuador of February 22 and at 106 degrees from the M 7.0 in Peru of March 1. Seismic energy from large events such as these concentrates at this distance on the surface and can often be followed by increased seismicity at this distance.

 

O: 20MAR2019 06:51:58  37.3N   29.4E ML=3.8  EMSC   WESTERN TURKEY               

O: 20MAR2019 06:45:34  37.4N   29.4E ML=3.2  EMSC   WESTERN TURKEY               

O: 20MAR2019 06:47:11  37.4N   29.4E ML=3.2  EMSC   WESTERN TURKEY               

O: 20MAR2019 06:34:28  37.4N   29.4E mb=5.7  EMSC   WESTERN TURKEY               

O: 20MAR2019 06:34:28  37.4N   29.6E mw=5.7  ANSS   E of Acipayam Turkey

O: 20MAR2019 01:41:48  37.4N   29.5E ML=3.5  EMSC   WESTERN TURKEY               

O: 20MAR2019 06:38:20  37.5N   29.5E ML=4.4  EMSC   WESTERN TURKEY               

O: 20MAR2019 06:41:56  37.5N   29.5E Mw=4.5  EMSC   WESTERN TURKEY               

P: 21MAR2019 114318    38.0N   30.0E 3.5-5.4 AAAAA  Turkey                     

 

 

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in the western Andreanof Islands, Aleutians, Alaska. It was not reported felt in this remote area. The last earthquake in this region within about 100 km of this epicenter with M>=4.1 was an M 4.3 on March 11, 2019. 13 such events have occurred in this are with M>=4.1 during 2019 to date. Forecast 114367 had expected this earthquake was likely in this area around March 19.

 

O: 19MAR2019 16:25:26  51.3N  178.4W mb=4.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 19MAR2019 114367    51.0N  177.1W 3.5-5.1 AAAAA  Andreanoff Isls, Aleutians 

 

ENHANCED SEISMICITY CONTINUES IN KERMADEC ISLANDS, NEW ZEALAND

 

EARTHQUAKE SUMMARY FOR MARCH 18, 2019

 

The strongest seismicity in the world today occurred in the central Kermadec Islands of New Zealand. This continues the activation of the region which began about a week ago with the passage of a tropical cyclone through the area. That was accompanied by an M 6.3 in the Southern Kermadec Islands and a number of associated events and on March 15 by an M 5.5 in northern Kermadec Islands.

 

"An earthquake of M 5.5 also occurred today in the northern Kermadec Islands, New Zealand. It was not reported felt in this remote area. This is not an aftershock of the recent strong series in southern Kermadec Islands whihc occurred about 600 km to the south of this epicenter. It represents a new epicenter in this series." (March 15, 2019).

 

Today's activity in the central Kermadec Islands is midway between these two  series. It is the strongest event of M>=5.2 between 31 and 32 South latitude  in the Kermadec Islands since an M 5.4 on March 21, 2015.   Forecast 114454 had expected today's activity was likely around March 17 in  this region.

 

O: 18MAR2019 15:07:15  31.8S  177.5W Mw=5.0  EMSC   KERMADEC ISLANDS REGION      

O: 18MAR2019 14:59:39  31.8S  177.6W mb=4.9  EMSC   KERMADEC ISLANDS REGION      

O: 18MAR2019 14:30:21  31.8S  177.7W mb=5.2  EMSC   KERMADEC ISLANDS REGION      

P: 17MAR2019 114454    31.0S  179.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in Central Alaska. This is an unusual epicenter. The last between 60 and 64N and within the range 154-156W was an 4.3 on April 17, 2000 and prior to that an M 4.7 on April 27, 1992. The last earthquake within about 100 km of this epicenter with M>=4.1 was an M Forecast 114398 had expected an earthquake east of this epicenter was likely with moderate magnitude around March 14.

 

O: 18MAR2019 07:46:42  62.1N  154.2W mb=4.1  EMSC   CENTRAL ALASKA               

P: 14MAR2019 114398    62.7N  150.6W 3.2-4.9 BACAA  Central Alaska             

 

An earthquake of M 5.1 also occurred near the antipode of the Andreanof Islands, Alaska in the Bouvet Island region of the south Atlantic. The exact antipode is at 54N 172W which is an active seismic zone and could be promoted by events such as this in the Bouvet Islands. The event in the South Atlantic is the strongest within about 200 km of this epicenter since an M 5.2 on February 21, 2018. An M 6.6 on January 28, 2018 may be the mainshock that led to these more recent events.

 

O: 19MAR2019 03:26:28  54.3S    8.0E mb=5.1  EMSC   BOUVET ISLAND REGION         

 

MODERATE SEISMICITY CONTINUES IN INDONESIA

 

EARTHQUAKE SUMMARY FOR MARCH 17, 2019

 

The strongest earthquake in the world today occurred in the Sumba and Sumbawa area of Indonesia. It was preceded by an M 3.8 foreshock and followed by an M 4.7 aftershock about an hour later.

 

This series was probably triggered by stress redistribution following the M 5.5 in Lombok to the west about 350 km. This summary reported on that event in the previous issue as:

 

"NEIC reported the earthquake in Lombok, Indonesia was felt with maximum intensity IV in Praya Nusa, Tenggara Barat and in Matarm and III in Bali at Karangasem, Klungkung, Ubud, Denpasar and Kuta and possibly as far as Java, Indonesia. BMG reported it was felt with intensity VI in Sembahun; IV in Lombok; III-IV i Karagasem, and Sumbawa and II in Denpasar, Kuta, Lombok, Indonesia.

An aftershocks of M 5.2 was felt with intensity III-IV in Lombok, Mataram and Sumbawa and II in Denpasar and Kuta, Lombok, Indonesia. This is an aftershock of the strong earthquakes in Lombok of August. 2018 (M 6.4, 6.9, 6.3). The last earthquake in this sequence of M>=5.5 was an M 5.5 on December 6, 2018 and the last of larger magnitude was an M 5.8 on August 19, 2018." (March 16-17, 2019)

 

The last earthquake of M>=5.0 in the Sumba/Sumbawa area within about 150 km of today's epicenter occurred as a series in January 21-23 which included an M 6.4 and 6.0 about  100 km south of today's epicenter. Today's events may be regional aftershock  activity of those events.  Forecast 114218 had expected a moderate event in the Sumbawa region around March 12.

 

O: 17MAR2019 17:41:40   9.7S  119.0E mb=5.0  EMSC   SUMBA REGION, INDONESIA      

O: 17MAR2019 18:58:29   9.8S  119.0E mb=4.7  EMSC   SUMBAWA REGION, INDONESIA    

O: 17MAR2019 17:40:17   9.8S  119.1E ML=3.8  EMSC   SUMBA REGION, INDONESIA      

P: 12MAR2019 114218     8.0S  119.0E 4.0-5.5 BBAAA  Sumbawa Island area        

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the Northern Alaska aftershock zone. It was not reported felt in this area. This area became active with an M 6.3 on August 12, 2018. The last event of M>=4.2 in the area was an M 4.9 on January 14, 2019. The last of M>=5 was an M 5.1 on September 18, 2018. Forecast 114403 had expected a moderate aftershock in the area around March 16.

 

 

O: 17MAR2019 13:13:18  69.6N  144.2W mb=4.2  EMSC   NORTHERN ALASKA              

P: 16MAR2019 114403    69.0N  144.0W 3.0-4.9 AAAAA  Northern Alaska            

 

An unusual earthquake of M 4.3 hit the region south of the Komandorsky Islands and east of Kamchatka today. This may be an outer rise event signaling high stresses in the Kamchatka area and the possibility of a strong upcoming event. The only earthquake with M>=4.3 within about 100 km of this epicenter in the past 30 years was an M 4.7 on December 5, 1997 about 150 km northwest of today's epicenter. No earthquakes of M>=4.3 have been recorded in the area south of 53 North latitude in at least 30 years. Forecast 114379 had expected moderate regional seismicity around March 14.

 

O: 17MAR2019 23:03:09  52.6N  165.1E mb=4.3  EMSC   SOUTH OF ALEUTIAN ISLANDS    

P: 14MAR2019 114379    56.0N  163.0E 4.0-5.9 BCBAA  Komandorsky Isl            

 

GEOMAGNETIC ACTIVITY BRINGS ENHANCED SEISMCITY TO INDONESIA

 

EARTHQUAKE SUMMARY FOR MARCH 16, 2019

 

A new geomagnetic active period today was accompanied by enhanced seismicity throughout much of western and central Indonesia along the geomagnetic equator. Moderately large quakes in Indonesia and the Philippines to the north included an M 5.5 in Lombok/Bali; an M 5.4 in Mindoro, Philippines and a series of events of M 5.0-5.3 in the area from Sulawesi to the Molucca Sea and an M 5.4 in Southern Sumatra.  This summary noted the geomagnetic activity as:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 12. High latitude geomagnetic field saw active conditions  with AP at 20.  This is the strongest geomagnetic storm in nearly three weeks and it may help to promote seismicity near the geomagnetic equator and at high latitudes." (March 16-17, 2019)

 

NEIC reported the earthquake in Lombok, Indonesia was felt with maximum intensity IV in Praya Nusa, Tenggara Barat and in Matarm and III in Bali at Karangasem, Klungkung, Ubud, Denpasar and Kuta and possibly as far as Java, Indonesia. BMG reported it was felt with intensity VI in Sembahun; IV in Lombok; III-IV i Karagasem, and Sumbawa and II in Denpasar, Kuta, Lombok, Indonesia.

 An aftershocks of M 5.2 was felt with intensity III-IV in Lombok, Mataram and Sumbawa and II in Denpasar and Kuta, Lombok, Indonesia. This is an aftershock of the strong earthquakes in Lombok of August. 2018 (M 6.4, 6.9, 6.3). The last earthquake in this sequence of M>=5.5 was an M 5.5 on December 6, 2018 and the last of larger magnitude was an M 5.8 on August 19, 2018. Forecast 114421 had expected this event was likely with magnitude up to M 5.8 and within about 150 km of this epicenter around March 17.

 

O: 17MAR2019 07:07:27   8.6S  116.5E Mw=5.5  EMSC   LOMBOK REGION, INDONESIA     

O: 17MAR2019 07:07:27   8.4S  116.5E mw=5.5  ANSS   SW of Sembalunbumbung Indonesia

O: 17MAR2019 07:09:19  08.5S  116.5E MS=5.2  BMG  Felt with intensity III-IV

O: 17MAR2019 07:07:25  08.3S  116.6E MS=5.8  BMG  Felt with intensity VI

P: 17MAR2019 114421    10.0S  116.0E 4.0-5.8 ABAAA  Sumbawa Island area        

 

PHIVOLCS reported the earthquake in Mindoro, Philippines was felt with intensity III in Abra De Ilog, Occidental Mindoro, Calaca, Batangas; II in Puerto Galera, Oriental Mindoro, Paranaque City, Manila City, Bauan, BatangasMarivales, Rataan, Bailen, Cabite, Muntiniupa City, Tagaytay City and I in Paluan, Occidental Mindoro, Philippines. NEIC reported this earthquake of M 5.4 in Southern Tagalog, Philippines was felt with intensity II-III in the area(s) of Tingloy and Cainta, Southern Tagalog, Philippines. This event was possibly promoted from the stresses associated with TD 03W which continues to approach the Philippines from the east as noted in previous issues of this summary:

 

"TD 03W formed today in the area south of Guam with winds up to 353 kts. It is  expected to track directly to the west reaching Mindanao, Philippines around March 18. Some seismicity in this area is expected to be enhanced when landfall is made in this active seismic area." (March 14-16, 2019)

 

The last earthquake of M>=5.4 within about 150 km of this epicenter occurred as an M 5.5 on August 31, 2018. The last such event with larger magnitude was an M 6.2 on August 11, 2017. Forecast 114233 had expected today's epicentral area would be active around March 20.

 

O: 16MAR2019 09:58:20  13.6N  120.9E Mw=5.4  EMSC   MINDORO, PHILIPPINES         

O: 16MAR2019 09:58:20  13.6N  120.9E mw=5.4  ANSS   SSW of Tingloy Philippines

O: 16MAR2019 09:58:18  13.6N  120.6E MS=5.2  PHI  Felt with intensity III

P: 20MAR2019 114233    12.0N  122.0E 3.5-5.1 BBAAA  Luzon, Philippines         

 

BMG reported the M 5.3-5.6 in Sulawesi was felt with intensity II-III in Obi and II in Labuha, Maluku, Indonesia. The last earthquake within about 150 km of this epicenter with M>=5.6 occurred on January 3, 2013 with M 5.6. Most such subsequent activity has occurred about 250 km to the northwest in a swarm in November 10, 2014 and an M 6.1 about 200 km southeast of today's epicenter on February 26, 2018.   Forecast 114217 had expected activity in the area of Sulawesi around March 21.

 

O: 16MAR2019 07:30:39   1.0S  126.9E Mw=5.3  EMSC   KEPULAUAN SULA, INDONESIA    

O: 16MAR2019 07:30:40   1.0S  126.9E mw=5.3  ANSS   WNW of Laiwui Indonesia

O: 16MAR2019 07:30:40  01.0S  126.8E MS=5.6  BMG  Felt with intensity II-III

P: 21MAR2019 114217     1.0S  124.0E 4.0-5.5 BACAA  Sulawesi area              

 

BMG reported the M 5.1-5.5 in Southern Sumatra was felt with intensity III in Bengkulu and Kepahiang, Bengkulu, Indonesia. The last earthquake within about 200 km of this epicenter with M>=5.5 occurred on February 2, 2019 of M 6.1 and 5.9 and prior to that an M 6.4 on August 13, 2017. Forecast 114215 had expected activity in Southern Sumatra was likely around March 13.

 

O: 16MAR2019 22:29:30   3.2S  102.0E Mw=5.1  EMSC   SOUTHERN SUMATRA, INDONESIA  

O: 16MAR2019 22:29:28  03.5S  101.8E MS=5.5  BMG  Felt with intensity III

P: 13MAR2019 114215     7.0S  104.0E 4.0-5.8 BCBAA  So. of Sumatera            

 

A strong series of moderate earthquakes of M 4.4-4.9 occurred north of the Azores Islands today. These events on the Northern mid-Atlantic Ridge were not reported felt and probably are associated with volcanism along the rift. The last earthquake in the area within about 200 km of today's epicenters with M>=4.9 was an M 5.3 on February 16. 2019. The last event of M>4.9 in the area prior to that was an M 5.2 on July 14, 2016. Forecast 114347 had expected today's activity within about 100 km  was likely around March 16. This activity is located at the sixth node from the Ecuador quake of M 7.5 of February 22 and may have been promoted by it.

 

O: 17MAR2019 07:03:45  42.8N   29.9W ML=4.4  EMSC   AZORES ISLANDS REGION        

O: 16MAR2019 19:48:55  42.9N   29.6W mb=4.7  EMSC   AZORES ISLANDS REGION        

O: 17MAR2019 05:45:59  43.0N   29.2W mb=4.7  EMSC   AZORES ISLANDS REGION        

O: 16MAR2019 19:19:50  43.1N   29.4W mb=4.7  EMSC   NORTHERN MID-ATLANTIC RIDGE  

P: 16MAR2019 114347    42.0N   29.0W 4.0-5.6 AAAAA  No. Mid-Atlantic Ridge     

 

The strongest earthquake in the U.S. or Canada today was an M 4.4 in the Near Islands, Aleutians, Alaska. This event was not reported felt in this remote epicentral area. It is the strongest earthquake within the Near Islands with M>=4.4 since an  M 4.4 on February 9, 2019. The last of greater magnitude in the area was an M 4.6 on July 10, 2018. Forecast 114379 had expected the Near Islands would see a moderate earthquake around March 15. This earthquake is located at 104 degrees from the M 7.5 in Ecuador of February 22 and may have been promoted from concentrated energy from that source.

 

O: 16MAR2019 20:47:01  52.0N  171.2E mb=4.4  EMSC   NEAR ISLANDS, ALEUTIAN ISLANDS

P: 15MAR2019 114379    55.0N  169.0E 4.0-5.7 ACBAA  Near Islands               

 

MODERATE QUAKE IN MINDANAO, PHILIPPINES PROMOTED BY TD 03W

 

EARTHQUAKE SUMMARY FOR MARCH 15, 2019

 

The strongest earthquake of the day was an M 5.5 in Mindanao, Philippines. NEIC reported it was felt with intensity IV in Southern Mindanao at Buayan, Silway, and Koronadal and II-III in Glamang, Lila and Davao and in central Mindanao at Kidapawan. A foreshock of M 4.4 was felt with intensity IV in Ula, Southern Mindanao, Philippines. This activity may have been promoted by the arrival in the area of Tropical Depression 03W. This had been anticipated in previous issues of this summary as:

 

"TD 03W formed today in the area south of Guam with winds up to 353 kts. It is

expected to track directly to the west reaching Mindanao, Philippines around March 18. Some seismicity in this area is expected to be enhanced when landfall is made in this active seismic area." (March 14-15, 2019)

 

A foreshock of M 4.4 hit southeast of the epicenter of the mainshock within about half an hour of local solar midnight and might have encouraged the subsequent M 5.5. Another foreshock of M 5.0 occurred at the epicenter of the mainshock earlier in the day. The last earthquake of M>=5.5 within about 150 km of today's mainshock was an M 5.6 on July 3, 2019. An M 7.0 hit Mindanao on December 29, 2018 about 200 km southeast of today's epicenter and today's event may have been promoted by stress redistribution after that event. Forecasts 114192 and 114193 had expected this activity within about 50 km was likely around March 12-16.

 

O: 15MAR2019 19:00:14   5.6N  127.2E mb=4.4  EMSC   PHILIPPINE ISLANDS REGION    

P: 12MAR2019 114192     5.0N  127.0E 4.0-5.5 BAAAA  Halmahera                  

 

O: 15MAR2019 09:55:30   6.3N  125.4E ML=5.0  EMSC   MINDANAO, PHILIPPINES        

O: 15MAR2019 23:07:56   6.2N  125.4E mw=5.5  ANSS   ESE of Manga Philippines

O: 15MAR2019 23:07:56   6.3N  125.4E Mw=5.5  EMSC   MINDANAO, PHILIPPINES        

P: 16MAR2019 114193     6.0N  126.0E 4.0-5.4 AAAAA  Mindanao, Philippines      

 

TD 03W may also have triggered an M 4.9 today in the Mariana Islands south of Guam. In an earlier issue of this summary this had been expected as:

 

"A tropical cyclone may be forming south of Guam. This system is currently located at 6N 149E and moving to the west at 12 kts with winds up to 20 kts. Some enhanced seismicity in Guam and the Caroline Islands may accompany  this storm." (March 14, 2019)

 

An earthquake of M 5.1 hit about 150 km southeast of this epicenter on March 11, also in association with TD 03W, These are the first events in this region with M>=4.9 since November 14-15, 2018 when events of M 5.2 and 5.0 occurred. Forecast 114246 had expected this activity within about 100 km of this epicenter was likely around March 14.

 

O: 15MAR2019 21:17:26  12.6N  142.6E mb=4.9  EMSC   MARIANA ISLANDS REGION       

P: 14MAR2019 114246    13.0N  143.0E 4.0-5.6 AAAAA  So. Marianas/Guam          

 

An earthquake of M 5.5 also occurred today in the northern Kermadec Islands, New Zealand. It was not reported felt in this remote area. This is not an aftershock of the recent strong series in southern Kermadec Islands whihc occurred about 600 km  to the south of this epicenter. It represents a new epicenter in this series. The last earthquake with M>=5.5 within about 200 km of this event in the Kermadec Islands occurred January 10, 2019 with M 5.8. The only other such events in the past two years occurred on November 25, 2018 (M 5.6) and July 2, 2017 (M 5.8). Forecast 114441 had expected this event within about 100 km of this epicenter was likely around March 20.

 

O: 15MAR2019 17:53:32  27.6S  176.2W Mw=5.5  EMSC   KERMADEC ISLANDS REGION      

O: 15MAR2019 17:53:33  27.6S  176.3W mw=5.5  ANSS   Raoul Island New Zealand

P: 20MAR2019 114441    27.0S  177.0W 4.0-5.4 BAAAA  Tonga Islands               

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Unimak Island region of Alaska. It was not reported felt in this remote area. The last earthquake in the Unimak Island area with M>=4.8 within about 200 km of this epicenter was an M 5.1 on February 15, 2019 and prior to that an M 6.0 on December 31, 2018. Forecast 114387 had expected today's activity was likel between March 12 and 18. This event is located at 103 degrees from the Peru earthquake of M 7.0 of March 1 and was probably promoted by concentrated energy at this distance from that event.

 

O: 15MAR2019 12:05:08  53.7N  163.7W mb=4.8  EMSC   UNIMAK ISLAND REGION, ALASKA 

P: 12MAR2019 114387    54.1N  164.4W 3.5-5.1 BAAAA  Unimak Islands, Aleutians  

P: 18MAR2019 114387    54.3N  162.7W 3.5-5.2 BAAAA  Unimak Islands, Aleutians  

 

STRONG, DEEP EARTHQUAKES SHAKE BOLIVIA

 

EARTHQUAKE SUMMARY FOR MARCH 14, 2019

 

A strong M 6.3 earthquake at more than 300 km depth shook the area around Bolivia and Peru today. This is typical of deep focus quakes in this area, an while maximum intensity V was reported from Iquique and Tarapaca, Chile no major damage or casualties were reported. NEIC also gave intensity IV reported from Cochabamba and La Paz, Bolivia and Arica, Chile and III in Cliza and Tupiza Potosi, Bolivia and Tacna, Ilo Moquegua and Habaya, Peru and from Calama, Antofagasta, Chile and in general within about 700 km of the epicenter in Bolivia. CSN reported this earthquake was felt with intensity V in  Tarapaca at Camina; IV in Alto Hospicio, Huara, Iquique, La Tirana, Mamina, Pica, Pisagua and Pozo Almonte and III in Ujiria; in Antofagasta III at Calama and Tocopill and II in Maria Elena; in Atacama with III in Copiapo, Diego de Almagro and Tierra Amarilla; in Arica sith IV in Coya and III in Arica and Pocon Chile, Chile. IGP reported this earthquake was felt with intensity II-III in  Tarata, Tacna, Ilo, Peru. This earthquake occurred within about an hour of local solar midnight and was probably promoted by high earth tides which maximize at this hour. It is also located near the geomagnetic equator and may have been enhanced by geomagnetic effects. The last earthquake within about 200 km of this epicenter with M>=6.3 occurred on February 21, 2017 with M 6.5 about 200 km to the southeast of today's epicenter. Two other such earthquakes have occurred in the region in the past 30 years - an M 6.6 on May 22, 2998 and another M 6.6 on October 10, 1990.  Forecast 114420 had expected today'e epicenter was likely about 200 km to the west with magnitude up to M 5.5

 

O: 15MAR2019 05:03:49  17.9S   65.9W Mw=6.3  EMSC   COCHABAMBA, BOLIVIA          

O: 15MAR2019 05:03     17.9S   65.9W mb=6.3  GUC    Tarapaca at Camina; IV in Alto

O: 15MAR2019 05:03:50  17.9S   65.9W mw=6.3  ANSS   S of Cliza Bolivia

O: 15MAR2019 05:03     18.3S   66.3W mb=6.3  GUC    Tarata, Tacna, Ilo, Peru.    

P: 13MAR2019 114420    18.0S   69.0W 4.0-5.5 AACAA  So. Peru/Bolivia           

 

The second strongest earthquake of the day occurred in the area south of Sumatra with M 4.9. This may have been promoted by a new tropical cyclone south of this epicenter as noted in this summary:

 

"TC Savannah formed today in the South Indian Ocean south of Sumatra with winds up to 70 kts. It is expected to track to the west over the next several days. This is an area where seismicity is uncommon. No major activity is expected with this storm at this time. This storm may enhance seismicity at the antipode - 14N 86W in Costa Rica and Nicaragua to Mexico." (March 14-15, 2019" (March 14-15, 2019))

 

The M 4.9 followed a M 4.0 earlier in the day. It occurred 19 minutes after the M 6,3 in Bolivia. These events are separted by 153 degrees on the surface of the earth. A cusp of reflected and refracted seismic waves from Bolivia  (pDiff, PKP) were present at the time the event occurred south of Sumatra and probably helped trigger this event.

 

These events are located at an unusual epicenter. The last such event within

about 100 km of this with M>=4.9 occurred with M 5.3 on May 30, 2013. Most activity in the past six years has occurred about 150-200 km north of today's epicenter south of Sumatra.  Forecast 114215 had expected this activity was likely to the north around March 12.

 

O: 14MAR2019 17:26:36   3.8S   98.8E ML=4.0  EMSC   UTHWEST OF SUMATRA, INDONESIA

O: 15MAR2019 05:22:24   4.3S   98.7E ML=4.9  EMSC   SOUTHWEST OF SUMATRA, INDONESI

P: 12MAR2019 114215     2.0S   99.0E 4.0-5.6 BCAAA  So. of Sumatera            

 

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in Central Alaska. NEIC reported this earthquake of M 4.1 in Central Alaska was felt with intensity II-III in the area(s) of Talkeetna, Alaska.  This is typical of background activity in the area. The last event of M>=4.1 within about 100 km of this epicenter was an M 4.2 on August 15, 2018. The last of significantly larger magnitude was an M 5.0 on July 10, 2018. Forecast 114398 had expected this event within about 25 km of the epicenter was likely around March 13.

 

O: 15MAR2019 05:58:36  63.3N  151.0W mb=4.1  EMSC   CENTRAL ALASKA               

P: 13MAR2019 114398    63.2N  151.4W 3.2-4.9 AAAAA  Central Alaska             

 

MODERATELY LARGE QUAKE SHAKES HAWAII

 

EARTHQUAKE SUMMARY FOR MARCH 13, 2019

 

A moderately large M 5.5 shook much of the Island of Hawaii today. NEIC reported it was felt with maximum intensity V in Volcano, Pahala, and Papaikou and IV in Hawaii National Park, Pahoa, Mountain View, Kurtistown, Keaau, Hilo, Papeekeo, Honolulu, Fort Shafter, Vililani, and in general within about 100 km of the epicenter. This is probably a volcanic earthquake triggered by high tidal stresses. It occurred within half an hour of local solar midnight when tidal stresses maximize. Another possible promoter of this event was Tropical Cyclone Idai. This storm is located near the antipode of Hawaii and had been expected in this summary to enhance the seismicity in Hawaii which has been at low levels since about a year ago as:

 

"Tropical cyclone Idai (18S) continued today in the South Indian Ocean west of Madagascar with winds up to 115 kts. It is expected to track to the South and west over the next several days.  No seismicity is likely to be triggered by this storm at this time. The active region of Mayotte may see a promoted moderate quake. The antipode is in the Pacific Ocean at 19N 140W, east of Hawaii. Some seismicity in Hawaii may be promoted as 18S takes a path antipodal to that area." (March 11-13, 2019)

 

The last earthquake of M>=5.5 in Hawaii occurred at the end of the eruption of the spring of 2018 on June 4 and 5, 2018 (both M 5.5). The only earthquake of larger magnitude in Hawaii in the past 13 years was an M 6.9 on May 4, 2018. Prior to than an M 6.7 occurred on October 15, 2006 and as an M 5.8 on April 17, 1999, Unlike the surface events of June, 2018 today's quake was located at a depth of 7 km and was probably not directly associated with an eruption. It could, however, enhance the possibility of a future eruption in the area of Kilauea Volcano.

 

 

O: 13MAR2019 10:55:13  19.4N  155.2W mb=5.3  EMSC   ISLAND OF HAWAII, HAWAII     

O: 13MAR2019 10:55:13  19.3N  155.2W ml=5.5  ANSS   SSE of Volcano Hawaii

P: 14MAR2019 114229    19.5N  155.1W 3.0-4.4 AAAAA  Hawaii                     

 

MODERATE QUAKE SHAKES PUERTO RICO

 

EARTHQUAKE SUMMARY FOR MARCH 12, 2019

 

A moderate earthquake of M 4.6 shook the island of Puerto Rico today. NEIC reported maximum intensity V in Puerto Rico at Cayey and Aibonito with IV in Cidra, Caguas, Guaynabo, and III in Aguirre, Caguas, Humacao and an Juan. This is the strongest earthquake within about 100 km of this epicenter in Puerto Rico since an M 5.0 on December 24, 2010. Most activity since then, including an M 6.4 on January 13, 2014 has occurred about 150 km northwest of today's epicenter. The last in this series was an M 4.8 on August 18, 2017. An M 4.9 occurred about 200 km northeast of today's epicenter on November 14, 2018, the last such regional event at this magnitude level.   Forecast 113975 had expected today's event was likely within about 15 km of this epicenter around March 9.

 

Strong tidal effects related to the last new moon may have promoted this activity in Puerto Rico as noted in previous issues of this summary:

 

"The new moon will arrive on March 6 at 16:04 UT. Longitudes which are sub-solar at this time are near 60 West and sub-lunar at 120 East. These include the Caribbean and South  America in the west and Taiwan and Indonesia in the east among others. These regions will experience maximum tidal stresses at this time and a moderate to large earthquake near these longitude bands is possible in the next week. Other regions can be triggered by tidal stresses at this time, especially those where fluids are a mitigating factor in seismicity and in areas of vertical tectonics. Tidal triggering often occurs near local solar noon and/or midnight when earth tidal stresses are maximized." (March 4-7, 2019)

 

 

O: 12MAR2019 13:08:56  17.9N   66.1W mb=4.7  EMSC   PUERTO RICO REGION           

P:  9MAR2019 113975    18.0N   66.0W 3.4-4.9 BAAAA  Puerto Rico                

 

The strongest earthquake in the U.S. or Canada today was an aftershock of M 4.5 in Northern Alaska. It was not reported felt in this remote epicentral area.

The mainshock in this series occurred August 12. 2018 and included events of M 6.3 and 6.1 on  that date. The last event in the series of M>=4.5 was an M 4.9 on January 14, 2019 and prior to that an M 4.5 on January 9, 2019. Forecast 114403 had expected this event within about 50 km of this epicenter was likely around March 16.

 

O: 13MAR2019 02:42:25  69.6N  144.4W mb=4.5  EMSC   NORTHERN ALASKA              

P: 16MAR2019 114403    69.0N  144.0W 3.0-4.9 BAAAA  Northern Alaska            

 

Moderate earthquakes of M 4.3 and M 4.6 also occurred in another aftershock sequence in Northern Alaska today. This sequence in northwestern Alaska began with an M 5.3 to the northeast of today's epicenter on October 14, 2018 after more than seven years without such an earthquake in the area. This year the sequence migrated southwest on February 10 (M 4.8) and an M 5.2 on March 6, the only such events in the area since March 22, 2010 (M 4.5). Forecast 114402 had expected an event within about 100 km of this epicenter was likely around March 14. This activity is located at 102 degrees from the M 7.0 in Peru of March 1, a distance at which triggering is likely.

 

O: 12MAR2019 15:52:51  66.3N  157.3W Mw=4.3  EMSC   NORTHERN ALASKA              

O: 12MAR2019 15:52:51  66.3N  157.3W Mw=4.6  ANSS   NORTHERN ALASKA              

O: 12MAR2019 15:52:41  66.3N  157.3W Mw=4.3  ANSS   NORTHERN ALASKA              

P: 14MAR2019 114402    66.0N  155.0W 3.0-4.9 AAAAA  Northern Alaska            

 

The strongest earthquake in the world today was an M 5.2 in Shikoku, Japan. NEIC reported this earthquake of M 5.2 in Southwest Honshu, Japan was felt with intensity II-III in the area(s) of Japan in Hyogi, Osaka, Kyoto and Aichi Prefectures.  No major damage or casualties were reported with this unusual earthquake. It is the strongest within about 150 km of this epicenter since an M 5.4 on November 2, 2018 and prior to that on June 17, 2018. The last within closer distance of M>=6.2 was an M 5.2 on November 19, 2016. Forecast 114277 had expected activity to the east of this is Southern Honshu was likely around March 16.

 

O: 13MAR2019 04:48:49  33.8N  134.9E Mw=5.2  EMSC   SHIKOKU, JAPAN               

P: 16MAR2019 114277    33.0N  138.0E 3.5-5.1 BABAA  Central/So. Honshu Japan   

 

UNUSUAL EARTHQUAKE SHAKES ALABAMA AND FLORIDA

 

EARTHQUAKE SUMMARY FOR MARCH 11, 2019

 

The most unusual earthquake in the U.S. today was an M 3.1 in southern Alabama. NEIC reported this earthquake of M 3.1 in Alabama was felt with intensity II-III in the area(s) of Century, Pensacola and Jay, Florida and in Mobile, Atmore and Brewton, Alabama.  Florida seldom feels tremor from earthquakes, so this is a significant regional event. The last earthquake within about 200 km of this epicenter with M>=3.1 occurred on February 18, 2011 and prior to that an M 3.1 on May 16, 2008.  Forecast 114314 had expected an event was likely in this area around March 14 to the north of this epicenter.

 

O: 11MAR2019 18:36:21  31.0N   87.2W mb=3.1  ANSS   ENE of Flomaton Alabama       

P: 14MAR2019 114314    33.0N   87.0W 2.0-4.5 BBAAA  Southeast U.S.             

 

The strongest earthquakes in the U.S. or Canada today were a pair of aftershocks in the Andreanof Islands of the M 5.2 there yesterday. These events registered at M 4.0 and 4.2 but were not felt. This summary noted this activity in the

previous issue as:

 

 

"The strongest earthquake in Alaska today was an M 5.2 in the Andreanof Islands. This continues active conditions over the past week in the Aleutians. It was not reported felt in this remote area. The last earthquake within about 150 km of this epicenter in the Andreanof Islands with M>=5.2 occurred on January 5, 2019 with M 5.9 and prior to that as an M 6.3 on August 23, 2018. Forecast 114368 expected today's event in this area was likely around March 13." (March 11, 2019)

 

O: 11MAR2019 15:19:33  51.3N  178.5W ml=4.0  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

O: 11MAR2019 15:48:49  51.3N  178.5W ml=4.2  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 13MAR2019 114368    50.2N  179.0W 3.5-5.0 ABAAA  Andreanoff Isls, Aleutians 

 

The largest earthquake of the day was an M 5.8 in New Britain, Papua New Guinea. This continues active conditions in the region which began in early March with

a strong geomagnetic storm. PNG is located on the geomagnetic equator or just south of it. The last earthquake within about 150 km of this epicenter with M>=5.8 occurred on December 19, 2018 also with M 5.8. The only other such event in the region in the past year was an M 6.0 on July 19, 2018.  Forecast 114207 had expected this activity was likely in mid-March.

 

O: 11MAR2019 16:25:50   6.0S  149.0E Mw=5.8  EMSC   NEW BRITAIN REGION, P.N.G.   

P: 17MAR2019 114207     5.0S  148.0E 4.0-5.5 CAAAA  New Ireland                

 

A pair of moderately large earthquakes of M 5.4-5.8 and 5.2 also occurred in Northern Sumatra, Indonesia today.  BMG reported the M 5.8 was felt with intensity II-III in Gunung Sitoli, Aek Godang and Teluk Dalam and Madina and Mandailing Natal and II in Aceh Singkil, Sumatra, Indonesia. The M 5.2 was reported felt with intensity IV in Aceh Singkil; III-IV in Gunung Sitoli and Nias Utara; II-III in Teluk Dalam and Sibolga and II in Sidikalang, Dolok Sanggul and Subulussalam, Sumatra, Indonesia. NEIC reported this earthquake of M 5.4 in Northern Sumatra was felt with intensity II-III in the area(s) of Sibolga, Sumatra, Indonesia. These may have been promoted by antipodal effects following the M 7.6 in Ecuador or February 22, as they are within about 200 km of the true antipode of that event. At the time of the Ecuador earthquakes this summary noted possible antipodal effects in Sumatra as:

 

"A pair of moderate earthquakes in  northern Sumatra occurred several hours after the mainshock in Ecuador. These are located near the antipode of that event and may have been promoted by concentrated antipodal energy from Ecuador. The true antipode is at 2N 103E, north and east of the active seismic regions in Sumatra. But some triggering is likely in Sumatra in coming days." (February 22, 2019)

 

The event of M 5.4-5.8 is the strongest within about 200 km of this epicenter since an M 5.8 on September 1, 2016 and prior to that an M 6.1 on November 8, 2015. A major to  great earthquake of M 7.7-7.8 hit the area to the west of these events on April 6, 2010 and these probably represent continuing aftershocks from that event.  Forecasts 113927 and 114196 and 113925 had expected this activity in this area was likely between March 7 and 13.

 

O: 11MAR2019 16:34:29   1.1N   98.9E Mw=5.4  EMSC   NORTHERN SUMATRA, INDONESIA  

O: 11MAR2019 16:34:29  01.1N  098.7E MS=5.8  BMG  Felt with intensity II-III

P:  9MAR2019 113927     2.0N  100.0E 4.0-5.5 AAAAA  So. Sumatera               

P: 13MAR2019 114196     2.0N  100.0E 4.0-5.4 AAAAA  So. Sumatera               

 

O: 11MAR2019 13:26:26   2.0N   97.9E Mw=5.2  EMSC   NIAS REGION, INDONESIA       

O: 11MAR2019 13:26:24  01.9N  097.8E MS=5.5  BMG  Felt with intensity IV

P:  7MAR2019 113925     2.0N   96.0E 4.0-5.4 BABAA  Nicobar Islands            

P:  9MAR2019 113927     2.0N  100.0E 4.0-5.5 AABAA  So. Sumatera               

 

GLOBAL SEISMICITY ACTIVE

 

EARTHQUAKE SUMMARY FOR MARCH 10, 2019

 

A series of moderately large to large earthquake occurred around the world today. These included an M 6.1 in Papua New Guinea, Indonesia; an M 5.8 off the east coast of Honshu, Japan; two events of M 5.0-5.1 in Southeastern Alaska and in the Andreanof Islands, Aleutians; an M 5.8 in the north Atlantic on the Reykjanes Ridge; an M 5.4 in the Southwest Indian Ridge; and an M 6.2 in Fiji. This was a sudden shift from relative quiet global seismicity to active conditions and turned the earthquake map red. This activity was likely promoted by high tidal stresses associated with the new moon and by the end of the geomagnetic storm as noted in previous issues of this report:

 

“This (geomagnetic) storm is likely to promote moderate to strong seismicity along the geomagnetic equator and to a lesser extent at high latitudes.” (March 6-10, 2019)

 

The strongest of these was the M 6.2 in Fiji. This area was very active following several major earthquakes last year but in recent week has been relatively quiet. Today's event was not reported felt in this area. The last earthquake within about 200 km of this epicenter with M>=6.2 occurred on November 18, 2018 with M 6.8. These, including today's event appear to be aftershocks of an M 8.2 great quake on August 19, 2018. Forecast 114145 had expected today's event in this area was likely around March 7. This event of M 6.1 is at 101-103 degrees from the M 7.6 in Ecuador of February 22 and the M 7.0 in Peru of March 1. This is a distance at which concentrated seismic energy returns to the surface after large events and can help trigger seismicity at this distance.

 

O: 10MAR2019 08:12:24  17.9S  178.6W Mw=6.2  EMSC   FIJI REGION                  

O: 10MAR2019 08:23:55  17.9S  178.6W mb=5.1  EMSC   FIJI REGION                  

P:  7MAR2019 114145    17.0S  177.0W 4.0-5.6 BAAAA  Tonga Islands              

 

The strongest earthquake felt in the world today was an M 6.1 southeast of Papua New Guinea. NEIC reported it was felt with intensity II in Alotau Milne Bay, Papua New Guinea. The last earthquake within about 200 km of this epicenter in the D'Entrecasteau Islands with M>=6.1 occurred as an M 6.1 on May 22, 1995. The only other such event in the area at this magnitude level in the past 30 years was an M 6.1 on March 13, 1992. Forecast 114138 had expected today's epicenter would be activity within about 100 km of this around March 8.

 

O: 10MAR2019 15:54:05  10.0S  151.9E mb=4.9  EMSC   D'ENTRECASTEAUX ISLANDS REGION

O: 10MAR2019 12:48:00  10.1S  152.1E Mw=6.1  EMSC   D'ENTRECASTEAUX ISLANDS REGION

P:  8MAR2019 114138    10.0S  151.0E 4.0-5.6 AAAAA  New Ireland                

 

An M 5.8 earthquake occurred today off the east coast of Honshu, Japan. NEIC reported it was felt with intensity II in Japan in Miyagi, Ibaraki, Saitama and Tokyo Prefectures. An aftershock of M 5.1 was reported felt with intensity II in Kanagawa, Japan. The last earthquake within about 150 km of this epicenter with M>=5.8 occurred on July 20, 2017 with M  5.8. The last of larger magnitude was an M 6.9 on November 21, 2016. Forecast 114296 had expected today's activity was likely around March 12. This event is at 144 degrees from the M 7.0 in Peru of March 1, a distance at which triggering from concentrated seismic energy is considered likely.

 

O: 10MAR2019 18:43:44  36.8N  142.4E Mw=5.0  EMSC   OFF EAST COAST OF HONSHU, JAPA

O: 10MAR2019 17:24:15  36.8N  142.4E Mw=5.1  EMSC   OFF EAST COAST OF HONSHU, JAPA

O: 10MAR2019 17:10:51  36.8N  142.4E Mw=5.8  EMSC   OFF EAST COAST OF HONSHU, JAPA

P: 12MAR2019 114296    36.0N  141.0E 4.0-5.5 AAAAA  Off East Coast Honshu      

 

A series of moderate to moderately strong earthquakes occurred today in the Northern Mid-Atlantic Ridge in the Reykjanes area. The strongest of these was an M 5.8 preceded by events of M 5.2 and 5.3. These events were not reported felt in this remote area and were probably associated with volcanism on the Reykjanes Ridge. The M 5.8 is the strongest earthquake within about 200 km of this epicenter since an M 5.9 on September 10, 2017. No other such events have hit the area in the past 30 years. Forecasts 114102 and 114381 had expected this activity about 100 km southwest of these epicenters between March 9 and 12. These events are at the third node (120 degrees) from the M 7.6 in Ecuador of February 22 and were probably promoted from that source.

 

O: 10MAR2019 19:13:48  58.0N   31.3W mb=4.5  EMSC   REYKJANES RIDGE              

O: 10MAR2019 18:04:59  58.4N   32.0W Mw=5.8  EMSC   REYKJANES RIDGE              

O: 10MAR2019 18:04:59  58.3N   32.0W Mw=5.9  ANSS   REYKJANES RIDGE              

O: 10MAR2019 16:23:49  58.5N   31.9W Mw=5.2  EMSC   REYKJANES RIDGE              

O: 10MAR2019 17:58:46  58.6N   32.3W Mw=5.3  EMSC   REYKJANES RIDGE              

P:  9MAR2019 114102    57.0N   33.0W 4.0-5.6 ABAAA  North Mid-Atlantic Ridge   

P: 12MAR2019 114381    57.0N   33.0W 4.0-5.5 ABAAA  North Mid-Atlantic Ridge   

 

The strongest earthquake outside Alaska in the U.S. or Canada today was an M 4.3 in Alberta near Rocky Mountain House. NEIC reported it was felt with intensity II in Rocky Mountain House, Edmonton, Airdrie and Calgary, Alberta, Canada.

 

A series of moderate earthquakes occurred in Alaska today. These included an M 4.8 and 5.0 in Southeastern Alaska; an M 5.2 in the Central Andreanof Islands and an M 4.7 in Southern Alaska. The series in Southeastern Alaska began with an M 4.8 within about an hour of local solar noon and was probably promoted by tidal stresses which maximize at this hour. These are not aftershocks of the M 4.9 near Craig, Alaska which occurred yesterday. They were probably promoted by regional stress redistribution from that event, however. That event occurred about 700 km southeast of today's epicenter and had been described in the previous issue of this summary as:

 

"An unusual earthquake of M 4.9 shook the region of Southeastern Alaska near Craig today. NEIC reported this earthquake of M 4.8 in Southeastern Alaska was felt with intensity II-III in the area(s) of Craig, Klawock, Petersbrg, Elfin Cove Alaska. No damage was reported with this earthquake. It is the strongest within about 200 km of this epicenter since an M 5.9 six years ago on January 31, 2013. This followed an M 7.5 mainshock on January 5, 2013. Today's event is within about 30 km of the mainshock of January, 2013 and may be a long-term aftershock of that event, the strongest since 2013."(March 9-10, 2019)

 

Today's event in Southeastern Alaska is the strongest within about 200 km of  this epicenter in nearly five years. The last such event was an M 6.0 on July 17, 2014. Forecasts 114390 and 114393 had expected this activity was likely around March 12-15 within about 100 km of today's epicenter.

 

O: 11MAR2019 00:07:18  59.8N  141.6W Mw=5.0  EMSC   SOUTHEASTERN ALASKA          

O: 11MAR2019 04:35:46  59.8N  141.7W ML=3.3  EMSC   SOUTHEASTERN ALASKA          

O: 11MAR2019 02:20:15  59.8N  141.7W ML=3.6  EMSC   SOUTHEASTERN ALASKA          

O: 11MAR2019 00:12:33  59.8N  141.7W ml=3.1  EMSC   SOUTHEASTERN ALASKA          

O: 11MAR2019 00:11:09  59.9N  141.6W ml=3.2  EMSC   SOUTHEASTERN ALASKA          

O: 10MAR2019 22:40:10  59.9N  141.7W mb=4.8  EMSC   SOUTHEASTERN ALASKA          

P: 12MAR2019 114390    60.0N  137.0W 3.2-5.0 AABAA  Central Alaska             

P: 15MAR2019 114393    60.3N  143.1W 3.2-5.0 BAAAA  Central Alaska             

 

The M 4.7 in Southern Alaska also occurred within about an hour of local solar  noon and about an hour before the initiation of the series in Southeastern Alaska and like that series, was probably tidally promoted. This is the largest earthquake within about 150 km of this epicenter since an M 4.9 on January 2, 2019. Two such earthquakes have hit the area in the past year.  NEIC reported this earthquake of M 4.7 in Southern Alaska was felt with intensity II-III in the area(s) of Homer, Alaska. Forecast 114116 had expected this event within about 25 km of this epicenter was likely around March 8.

 

O: 10MAR2019 21:44:35  59.7N  153.4W mb=4.7  EMSC   SOUTHERN ALASKA              

P:  8MAR2019 114116    60.0N  153.5W 3.2-4.9 AAAAA  Central Alaska             

 

The strongest earthquake in Alaska today was an M 5.2 in the Andreanof Islands. This continues active conditions over the past week in the Aleutians. It was not reported felt in this remote area. The last earthquake within about 150 km of this epicenter in the Andreanof Islands with M>=5.2 occurred on January 5, 2019 with M 5.9 and prior to that as an M 6.3 on August 23, 2018. Forecast 114368 expected today's event in this area was likely around March 13.

 

O: 11MAR2019 06:23:15  51.6N  178.4W Mw=5.2  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 13MAR2019 114368    50.2N  179.0W 3.5-5.0 AAAAA  Andreanoff Isls, Aleutians 

 

An unusual earthquake of M 4.3 also occurred in Alberta, Canada today. An earthquake of M 4.3 hit about 75 km south of this on August 9, 2014, the only such event in this region at this magnitude level or above during the past 30 years. The events in Southeastern Alaska over the past two days and this event may reflect a regional stress begin expressed. Forecast 114366 had expected this area to be active within about 75 km in mid-March.

 

O: 10MAR2019 10:00:34  52.7N  114.9W mb=4.3  EMSC   ALBERTA, CANADA              

P: 21MAR2019 114366    52.0N  115.0W 2.0-3.9 CAAAA  Alberta                    

 

A series of moderate earthquakes occurred in the area of the Southwest Indian Ridge today. These were not reported felt in this remote area. An M 5.4 was the largest of these events. The antipode of this activity is located west of Southern California and some antipodal triggering could occur in this area. Forecasts 114174 and 114453 had expected the Indian Ridge activity was likely in mid-March.

 

O: 11MAR2019 03:15:30  31.7S   58.0E mb=5.1  EMSC   SOUTHWEST INDIAN RIDGE       

P:  7MAR2019 114174    33.0S   57.0E 4.0-5.6 BBAAA  So. Indian Ocean           

 

O: 10MAR2019 18:34:47  35.1S   53.8E mb=4.8  EMSC   SOUTHWEST INDIAN RIDGE       

O: 10MAR2019 13:18:16  35.3S   53.9E mb=5.4  EMSC   SOUTHWEST INDIAN RIDGE       

P:  7MAR2019 114174    33.0S   57.0E 4.0-5.6 BCCAA  So. Indian Ocean           

P: 19MAR2019 114453    34.0S   56.0E 4.0-5.6 CBBAA  So. Indian Ocean           

 

The most unusual earthquake in the world today occurred in the Mozambique Channel with M 4.8. This was not reported felt. It may have been promoted by Tropical Cyclone Idai which is currently in the Mozambique Channel. This possibility had been discussed in previous summaries as:

 

"Tropical cyclone Idai (18S) continued today in the South Indian Ocean north of Madagascar with winds up to 110 kts. It is expected to track to the South and west over the next several days.  No seismicity is likely to be triggered by this storm at this time. The active region of Mayotte may see a promoted moderate quake."(March 9-10, 2019)

 

This is the first earthquake in the Mozambique Channel within about 200 km

of this epicenter with M>=4.0 since an M 4.0 on September 1, 2012 and the largest in the area in at least 30 years. Forecast 114158 had expected today's event was likely to the northeast around March 11.

 

O: 10MAR2019 18:35:58  25.5S   36.7E mb=4.8  EMSC   MOZAMBIQUE CHANNEL           

P: 11MAR2019 114158    21.0S   33.0E 4.0-5.5 ACCAA  So. Indian Ocean           

 

 

 

 

UNUSUAL EARTHQUAKE SHAKES SOUTHEASTERN ALASKA

 

EARTHQUAKE SUMMARY FOR MARCH 9, 2019

 

An unusual earthquake of M 4.9 shook the region of Southeastern Alaska near Craig today. NEIC reported this earthquake of M 4.8 in Southeastern Alaska was felt with intensity II-III in the area(s) of Craig, Klawock, Petersbrg, Elfin Cove Alaska. No damage was reported with this earthquake. It is the strongest within about 200 km of this epicenter since an M 5.9 six years ago on January 31, 2013. This followed an M 7.5 mainshock on January 5, 2013. Today's event is within about 30 km of the mainshock of January, 2013 and may be a long-term aftershock of that event, the strongest since 2013. Forecast 114095 had expected today's event within  about 30 km of this epicenter was likely around March 7 with magnitude up to M 5.3. This is the strongest earthquake in the world today as no events of M>=5 were recorded.

 

O:  9MAR2019 11:10:59  55.3N  134.9W Mw=4.9  EMSC   SOUTHEASTERN ALASKA          

P:  7MAR2019 114095    55.0N  135.0W 3.0-5.3 AAAAA  British Colombia           

 

Two moderate earthquakes occurred today in the Dominican Republic with M 4.3 and 3.9.  NEIC reported this earthquake of M 3.6 in Dominican Republic was felt with intensity II-III in the area(s) of Otra Banda, La Altagracia, Dominican Republic. The M 4.2 is the strongest in the Dominican Republic since an M 4.4 on November 11, 2018 and  prior to that an M 5.2 on September 23, 2018, the only such events in the past year. These events are near the longitude where tidal stress was maximized at the new moon of March 6 and may have been promoted by tidal stresses. Forecast 113981 had expected this activity was likely around March 8.

 

O:  9MAR2019 10:50:39  17.9N   72.0W ML=4.3  EMSC   DOMINICAN REPUBLIC REGION    

P:  8MAR2019 113981    20.0N   71.0W 3.0-4.8 ACAAA  Bahamas/No. Caribbean      

 

O:  9MAR2019 18:11:02  18.8N   68.1W ML=3.9  EMSC   DOMINICAN REPUBLIC REGION    

P:  9MAR2019 113975    18.0N   66.0W 3.4-4.9 AABAA  Puerto Rico                

 

An earthquake of M 4.7 also occurred today in southern Guerrero, Mexico. NEIC reported this earthquake of M 4.7 in Guerrero, Mexico was felt with intensity II-III in the area(s) of Zihuatanejo, Guerrero and in Mexico City, Mexico. This is the strongest earthquake within about 100 km of this Guerrero epicenter since an M 4.9 on May 16, 2018, the only such event in the past year. An M 4.9 occurred about 150 km northwest of today's epicenter on March 2, 2019.  Forecast 113973 expected this event within about 50 km of the epicenter was likely around March 7.

 

O:  9MAR2019 19:14:40  17.4N  100.6W ML=4.0  EMSC   GUERRERO, MEXICO             

O:  9MAR2019 14:00:53  17.5N  100.3W mb=4.7  EMSC   GUERRERO, MEXICO             

P:  7MAR2019 113973    17.0N  100.0W 3.5-5.1 AAAAA  Oaxaca, Mexico             

 

STRONG QUAKE SHAKES NORTHERN MINDANAO, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR MARCH 8, 2019

 

A strong earthquake of M 6.0-6.3 in Northern Mindanao/Leyte, Philippines today continued the activation near 120 degrees East Longitude which was expected with high tidal effects from the new moon. Today's earthquake was reported by NEIC to have been felt in Caraga, Philippines with intensity II in Sapao, Pilar, Purok, Brasilisa, Calver, Tandag and in the Eastern Visayas at Batangiga, Sogod, Javier, Baybay. PHIVOLCS reported this event at M 6.3 was felt with intensity V in Burgos, Dapa, Alegria, Bacuag, Claver, General Luna, Gigaquit, Pilar, Placer and San Benito, Surigao Del Norte, Surigao City, San Jose, Dinagat; IV in Butuan City, Malimono, Surigao Del Nore, Tacloban City; Abuyog and Palo, Leyte, Anahawan, Hinunangan, Hinundayan, Limasawa, San Francisco, , Agusan Del Norte; III in Gingoog City, Tandag City, Salcedo Eastern Samar; II in Bislig City, Cagayan De Oro City, Ormoc City, Mambajao and Mahinog, Camiguin and I in Davao city, Philippines. No major damage was reported. This summary had anticipated this event in the previous report as:

 

"A pair of moderate earthquakes of M 4.2 and 4.3 also shook Leyte, Philippines today. PHIVOLCS reported the M 4.2 was felt with intensity III in Guiuan and Salcedo, Eastern Samar andII in Gen McArthur and Hernani, Eastern Samar, Philippines. The M 4.3 was felt with intensity V in Hinunangan, Southern Leyte; IV in Silago, Hinundayanm St Bernard, San Francisco, San Juan and Anahawan, Southern Leyte; III in Bontoc, Southern Laytem Abuyog Leyte and II in Dulag, Leytem Philippines. These events occurred near the longitude of maximum tidal stress from the new moon yesterday. A strong earthquake is possible in this active zone associated with the new moon in the next several days. Forecast 113963 had expected this activity was likely in early March." (March 7-8, 2019)

 

Note that these two event were true foreshocks to today's M 6.0-6.3 having occurred within about 35 km of this epicenter.

 

The tidal forecast for seismicity had also noted this area as possible for a stronger event associated with the new moon as:

 

"The new moon will arrive on March 6 at 16:04 UT. Longitudes which are sub-solar at this time are near 60 West and sub-lunar at 120 East. These include the Caribbean and South  America in the west and Taiwan and Indonesia in the east among others. These regions will experience maximum tidal stresses at this time and a moderate to large earthquake near these longitude bands is possible in the next week. Other regions can be triggered by tidal stresses at this time, especially those where fluids are a mitigating factor in seismicity and in areas of vertical tectonics. Tidal triggering often occurs near local solar noon and/or midnight when earth tidal stresses are maximized." (March 4-7, 2019)

 

Another factor which probably promoted this earthquake at this time was the occurrence of a C-class solar flare which occurred while this epicenter was sub-solar point, a prime time for solar flare triggering. This epicenter was directly beneath the sun - at high noon - when the flare occurred. This is the strongest solar flare since a C5.2 on January 30, 2019, the only such flare in the past six months. SWPC gives the following parameters for this flare:

 

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

8550       0307   0319      0358   C1.3      (March 8, 2019)   3.0E-03  

 

Today's M 6.0 is the strongest in the Leyte area of the Philippines within about 200 km of this epicenter since an M 6.5 on February 10, 2017 and prior to that an M 6.0 on July 3, 2015. Forecast 114918 had expected this event was likely within this area around March 6.

 

O: 08MAR2019 15:06:13  10.3N  126.1E MS=6.3  PHI  Felt with intensity V

O:  8MAR2019 15:06:14  10.4N  126.0E Mw=6.0  EMSC   PHILIPPINE ISLANDS REGION    

P:  6MAR2019 113918     9.0N  126.0E 4.0-5.6 ABAAA  Central Philippines        

 

 

The strongest earthquakes in the U.S. or Canada today continued to occur in the  Aleutians with an M 4.2 in the Rat Islands and an M 4.1 in the Central Andreanof Islands. These are apparently aftershocks of stronger regional events in the past several days. They were not felt in these remote areas. The Rat Islands event had been forecast in 114106 within about 100 km of the epicenter while  the event in the Andreanof Islands had been expected around March 6 in forecast 114093,

 

O:  8MAR2019 16:20:31  52.1N  177.7E mb=4.2  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P:  4MAR2019 114106    51.0N  177.0E 4.0-6.0 BBAAA  Rat Islands                

 

O:  9MAR2019 01:16:03  52.6N  175.7W mb=4.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  6MAR2019 114093    51.9N  176.0W 3.5-4.9 BAAAA  Andreanoff Isls, Aleutians 

 

As Tropical Cyclone Pola dissipated and moved out of the Kermadec Islands, regional seismicity continued but at a reduced magnitude level. This follows an M 6.4 in the area two days ago and had been anticipated in forecasts 114171 and 114175.

 

O:  8MAR2019 11:00:06  30.5S  178.9W mb=4.8  EMSC   KERMADEC ISLANDS, NEW ZEALAND

P: 11MAR2019 114171    30.0S  178.0W 4.0-5.4 BAAAA  No. Kermadec Islands       

 

O:  8MAR2019 09:48:05  32.0S  178.0W mb=4.9  EMSC   SOUTH OF KERMADEC ISLANDS    

O:  8MAR2019 11:57:17  32.3S  177.9W mb=5.0  EMSC   SOUTH OF KERMADEC ISLANDS     

P:  6MAR2019 114175    34.0S  179.0W 4.0-5.5 ABAAA  So. Kermadec Islands       

 

O:  8MAR2019 12:51:36  32.4S  176.0W mb=5.0  EMSC   SOUTH OF KERMADEC ISLANDS    

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 BBBAA  So. Kermadec Islands       

P:  6MAR2019 114175    34.0S  179.0W 4.0-5.5 ABCAA  So. Kermadec Islands       

 

IDAL PROMOTION STRONG IN WESTERN PACIFIC RIM

 

EARTHQUAKE SUMMARY FOR MARCH 7, 2019

 

 

Strong tidal promotion of seismicity occurred today in the western Pacific subduction zone. Moderately large earthquakes near the longitude of maximum tides occurred as an M 5.7 in Central Chile and an M 5.4 in Taiwan. Among the events was a moderate earthquake of M 5.4 shook regions of Taiwan today. This event was reported by NEIC to have been felt with intensity II-III in Kaohsiung and Taipei, Taiwan. It was probably promoted by tidal stresses which maximized near this longitude with the new moon as noted in previous issues of this summary:

 

 

"The new moon will arrive on March 6 at 16:04 UT. Longitudes which are sub-solar at this time are near 60 West and sub-lunar at 120 East. These include the Caribbean and South  America in the west and Taiwan and Indonesia in the east among others. These regions will experience maximum tidal stresses at this time and a moderate to large earthquake near these longitude bands is possible in the next week. Other regions can be triggered by tidal stresses at this time, especially those where fluids are a mitigating factor in seismicity and in areas of vertical tectonics. Tidal triggering often occurs near local solar noon and/or midnight when earth tidal stresses are maximized." (March 4-7, 2019)

 

CWB reported the earthquake in Taiwan of M 5.2 was felt with intensity IV in Taitung; III in Pingtung; II in Hualien and Kaohsiung and I in Chiayi, Tainan, Yunlin, Nantou and Taichung Counties, Taiwan. The M 4.0 was felt with intensity II in Taitung and I in Pingtung Counties. No damage was reported. The last event in Taiwan within about 200 km of this epicenter with M>=5.4 was an M 5.7 on October 23, 2018 and prior to that an M 5.7 on February 7, 2018. Forecast 113992 had expected a moderately larger event up to M 5.4 in Taiwan around March 7.

 

O:  8MAR2019 02:32:13  22.4N  121.5E Mw=5.4  EMSC   TAIWAN REGION                

O:  8MAR2019 02:32:14  22.4N  121.4E ML=5.2  TAI    Hualien, Taiwan               

O:  8MAR2019 02:55:18  22.4N  121.4E ML=4.0  TAI    Hualien, Taiwan              

P:  7MAR2019 113992    24.0N  121.0E 4.0-5.4 ABAAA  Taiwan                     

 

A pair of moderate earthquakes of M 4.2 and 4.3 also shook Leyte, Philippines today. PHIVOLCS reported the M 4.2 was felt with intensity III in Guiuan and Salcedo, Eastern Samar andII in Gen McArthur and Hernani, Eastern Samar, Philippines. The M 4.3 was felt with intensity V in Hinunangan, Southern Leyte; IV in Silago, Hinundayanm St Bernard, San Francisco, San Juan and Anahawan, Southern Leyte; III in Bontoc, Southern Laytem Abuyog Leyte and II in Dulag, Leytem Philippines. These events occurred near the longitude of maximum tidal stress from the new moon yesterday. A strong earthquake is possible in this active zone associated with the new moon in the next several days. Forecast 113963 had expected this activity was likely in early March.

 

O:  7MAR2019 14:20:28  10.4N  125.1E MS=4.3  PHI  Felt with intensity V in Hinunan

O:  7MAR2019 18:10:57  10.8N  125.7E MS=4.2  PHI  Felt with intensity III in Guiua

P:  2MAR2019 113963    10.0N  126.0E 3.5-5.1 BAAAA  Luzon, Philippines         

 

An earthquake of M 5.7 also shook Central Chile in the area of Coquimbo. This event was off the coast and was felt with intensity II in Coquimbo at Coquimbo, La Serena, Ovalle, Vicuna, Monte Patria, Vallenar, Quilpue and Santiago, Chile.

CSN reported this earthquake was felt with intensity V in  Coquimbo at Coquimgo, Illapel, La Serena, Mone Patria, Rio Hurtado; IV in La Higuera, Ovalle, Paiguano, Vicuna and III in Canela, Combarbala, Salamanca; in Valparaiso with III in San Felipe and in Atacama with IV in Freirina and III in Alto del Carmen, Copiapo, Huasco, Tierra Amarilla and Vallenar, Chile. This earthquake is north of the active aftershock zone in Coquimbo and is the strongest within about 100 km of this epicenter since an M 6.7 on January 20, 2019 about 150 km southeast of today's event. The last of larger magnitude within the 100 km range was an M 5.8 about 100 km southeast on August 12, 2017.  Forecast 114152 had expected today's earthquake was likely in this area around March 5. Today's event was probably promoted by tidal effects related to the new moon. It occurred within about an hour of local solar noon, a time when tidal forces are maximized, in a longitude of high tidal stresses with the new moon of March 6.

 

O:  7MAR2019 15:34:27  29.5S   72.6W Mw=5.7  EMSC   OFF COAST OF COQUIMBO, CHILE 

O:  7MAR2019 15:34     29.6S   72.5W mb=5.7  GUC    Coquimbo at Coquimgo, Illapel,

P:  5MAR2019 114152    29.0S   71.0W 4.0-5.8 AAAAA  Coast Central Chile        

 

An unusual earthquake of M 4.8 was widely felt in South Africa today. NEIC reported intensity II ini Gauteng at Westoriana, Cantonville, Vanderbiltpark, Randvaal, Krugersdorp and Johannesburg and in Sasciburg Free State and Fochville North West, South Africa. This is the second moderate earthquake in South Africa this week, an unusual occurrence. The last such event was an M 4.8 on March 1, 2019, the largest in the area since an M 5.2 on April 3, 2017. Forecast 114156 had expected today's earthquake within about 75 km of this epicenter was likely around March 8. Like other activity today, this event was probably tidally promoted as it occurred within about 30 minutes of local solar noon, a time when tidal forces are maximized. These events are at 101 degrees from the M 7.5 in Ecuador of February 22 and were probably promoted from that source.

 

O:  7MAR2019 09:32:35  26.5S   27.5E mb=4.8  EMSC   SOUTH AFRICA                 

P:  8MAR2019 114156    27.0S   27.0E 3.0-4.7 AAAAA  Rep. South Africa          

 

The strong seismicity in the region of the southern Kermadec Islands continued to migrate south today with moderately strong events of M 5.5 and 5.7 included. These events are near 100 degrees from the M 7.5 in Ecuador of February 22 and may have been promoted by concentrated seismic energy from that event.  This activity has been followed over the past several days in this summary as it relates to Tropical Cyclone Pola. In the previous issue it was noted in this regard:

 

 

"The strongest earthquake on a active day today occurred in the southern Kermadec Islands, New Zealand with M 6.3-6.4. It was followed by aftershocks of M 5.7, 5.1 and 5.0 among others. None of these events were reported felt in this remote region. This summary has been following the southward migration of a series of earthquakes in the Kermadec Islands which have been associated with the passage of Tropical Cyclone Pola through the area. In previous issues of this summary this had been noted as:

 

 

"Seismicity also continued to migrate to the south in the Mermadec Island, New Zealand today. This follows several quakes in the area yesterday which were probably promoted by a Tropical Cyclone passing through the region. This had been noted in the previous summary as:

 

 

"The strongest earthquakes in the world today were a pair of events in the Kermadec Islands of northern New Zealand. These events occurred as the remnants of Tropical Cyclone Pola were passing through the region and were probably promoted by stresses associated with TC Pola. This summary had suggest in earlier issues that this was a possibility at this time as:

 

"Tropical cyclone Pola (16F) continued today near the Kermadec Islands with winds up to 50 kts. It could help promote seismicity in the Kermadec – North Island, New Zealand region in the next several days." (March 1-2, 4-5, 2019)

 

Forecast 114175 had expected today's event within about 100 km was likely around March 4. More such activity may occur in the Kermadec Islands with this storm, including the possibility of a strong quake in this active area." (March 5-7, 2019)

 

Today's activity continued the march of these epicenters to the south. The last event of M>=5.7 within about 100 km of the M 5.7 today was the M 6.4 yesterday about 75 km to the northeast. The last of greater magnitude prior to that was an M 5.8 on December 4, 2017.  Forecast 114175 had expected this activity was likely in this epicentral zone around March 4-6.

 

O:  7MAR2019 13:02:40  32.3S  178.0W mb=4.9  EMSC   SOUTH OF KERMADEC ISLANDS    

O:  7MAR2019 16:29:10  32.6S  178.2W Mw=5.7  EMSC   SOUTH OF KERMADEC ISLANDS    

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 ABAAA  So. Kermadec Islands       

P:  6MAR2019 114175    34.0S  179.0W 4.0-5.5 ABAAA  So. Kermadec Islands       

 

O:  7MAR2019 15:27:22  32.8S  176.7W Mw=5.5  EMSC   SOUTH OF KERMADEC ISLANDS    

P:  6MAR2019 114175    34.0S  179.0W 4.0-5.5 ABBAA  So. Kermadec Islands       

 

The strongest seismicity in the U.S. or Canada today occurred in Alaska in the Andreanof Islands (M 5.1) and the Unimak Island area (M 4.7) and in the Alaska Peninsula (M 4.8). While none of these are unusual, having three moderate events in the region in one day is a bit odd. The event most likely promoted by tidal stresses associated with the new moon was the M 4.8 in the Alaska Peninsula which occurred within minutes of local solar noon, a time at which tidal forces maximize. The largest of today's events in Alaska was an M 5.1 in the central Andreanof Islands, Aleutians. It was not reported felt in this remote epicentral area. The last event of M>=5.1 within about 200 km of this epicenter was an M 5.2 on July 9, 2018 and an M 5.1 on February 16, 2018. The last of significantly larger magnitude was an M 5.9 on May 8, 2017. Forecast 114093 had expected today's earthquake was likely around March 6 within about 50 km of the epicenter.

 

O:  7MAR2019 09:45:58  51.7N  175.3W Mw=5.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P:  6MAR2019 114093    51.9N  176.0W 3.5-4.9 AAAAA  Andreanoff Isls, Aleutians 

 

The last earthquake in the Unimak Island region of Alaska of larger or equal magnitude to today's M 4.7 occurred on February 15, 2019 (M 5.1) and prior to that as an M 4.7 on October 12, 2018. Forecast 114111 had expected today's activity near Unimak was likely within about 50 km of this epicenter around March 6.

 

O:  7MAR2019 16:29:49  54.9N  164.9W mb=4.7  EMSC   UNIMAK ISLAND REGION, ALASKA 

P:  6MAR2019 114111    54.2N  165.0W 3.5-5.1 AAAAA  Unimak Islands, Aleutians  

 

The M 4.8 in the Alaska Peninsula today is the strongest within about 150 km

of this epicenter since an M 5.2 on January 22, 2019 and prior to that an M 5.3 on May 11, 2018. NEIC reported this earthquake of M 4.8 in the Alaska Peninsula was felt with intensity II-III in the area(s) of Saouth Naknek, Kodiak, Homer, and Soldotna, Alaska. Forecast 114112 had expected this activity was likely around March 6 in the Alaska Peninsula.

 

O:  7MAR2019 22:11:49  58.6N  155.2W Mw=4.8  EMSC   ALASKA PENINSULA             

P:  6MAR2019 114112    57.2N  157.0W 3.5-5.1 ABBAA  Alaska Peninsula           

 

An earthquake of M 3.8 in the Gulf of California today may have been promoted by antipodal microseisms from TC Haleh in the South Indian Ocean. This summary had noted this possibility in previous issues as:

 

 

"Tropical cyclone Haleh (17S) continued today in the South Indian Ocean with winds up to 135 kts. It is expected to track to the South over the next several days.  No seismicity is likely to be triggered by this storm at this time. The antipode is in Jalisco, Western Mexico in the Gulf of California at 23N 110W. Some minor enhancement of seismicity in Jalisco and Colima areas of Mexico could occur due to antipodal effects from Haleh." (March 6-7, 2019)

 

Note that the position of the epicenter in the Gulf of California was within about 100 km of the exact antipode as defined in this forecast.

 

O:  8MAR2019 04:19:02  23.0N  109.0W ML=3.8  EMSC   GULF OF CALIFORNIA            

P:  9MAR2019 113984    25.0N  113.0W 3.5-5.1 ABCAA  Gulf of California         

P: 27FEB2019 113734    24.0N  109.0W 3.5-4.9 CAAAA  Gulf of California         

 

STRONG EARTHQUAKE SHAKES KERMADEC ISLANDS, NEW ZEALAND

 

EARTHQUAKE SUMMARY FOR MARCH 6, 2019

 

The strongest earthquake on a active day today occurred in the southern Kermadec Islands, New Zealand with M 6.3-6.4. It was followed by aftershocks of M 5.7, 5.1 and 5.0  among others. None of these events were reported felt in this remote region. This summary has been following the southward migration of a series of earthquakes in the Kermadec Islands which have been associated with the passage of Tropical Cyclone Pola through the area. In previous issues of this summary this had been noted as:

 

 

"Seismicity also continued to migrate to the south in the Mermadec Island, New Zealand today. This follows several quakes in the area yesterday which were probably promoted by a Tropical Cyclone passing through the region. This had been noted in the previous summary as:

 

 

"The strongest earthquakes in the world today were a pair of events in the Kermadec Islnads of northern New Zealand. These events occurred as the remnants of Tropical Cyclone Pola were passing through the region and were probably promoted by stresses associated with TC Pola. This summary had suggest in earlier issues that this was a possibility at this time as:

 

"Tropical cyclone Pola (16F) continued today near the Kermadec Islands with winds up to 50 kts. It could help promote seismicity in the Kermadec - North Island, New Zealand region in the next several days." (March 1-2, 4-5, 2019)

 

Forecast 114175 had expected today's event within about 100 km was likely around March 4. More such activity may occur in the Kermadec Islands with this storm, including the possibility of a strong quake in this active area." (March 5-6, 2019)

 

The last earthquake within about 200 km of today's epicenter with M>=6.3 occurred as an M 6.9 on September 10, 2018 and prior to that an M 6.3 on July 13, 2016 and July 3, 2014. Forecast 114175 had expected this activity in the Kermadec Islands was likely in early March.

 

O:  6MAR2019 15:59:00  31.9S  177.8W mb=5.0  EMSC   KERMADEC ISLANDS REGION      

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

 

O:  6MAR2019 15:46:11  32.1S  177.8W Mw=6.3  EMSC   SOUTH OF KERMADEC ISLANDS    

O: 06MAR2019 15:46:14  32.0S  177.9W mw=6.4  ANSS   L'Esperance Rock New Zealand

O:  6MAR2019 21:42:52  32.2S  177.5W mb=5.1  EMSC   SOUTH OF KERMADEC ISLANDS    

O:  6MAR2019 20:19:57  32.2S  177.8W Mw=5.7  EMSC   SOUTH OF KERMADEC ISLANDS    

O:  7MAR2019 02:27:05  32.4S  178.2W mb=5.0  EMSC   SOUTH OF KERMADEC ISLANDS     

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

P:  6MAR2019 114175    34.0S  179.0W 4.0-5.5 ABAAA  So. Kermadec Islands       

 

A moderately strong M 5.6 also occurred in the eastern South Pacific Ocean today with M 5.6 on the West Chile Rise. It was not reported felt in this remote oceanic area. The last earthquake within about 200 km of this epicenter on the West Chile Rise with M>=5.6 was an M 5.9 on May 6, 2014 and prior to that an M 5.8 on August 16, 2012.  Forecast 114169 had expected today's event within about 50 km of this epicenter was likely around March 8.

 

O:  6MAR2019 07:20:45  36.2S   97.5W Mw=5.6  EMSC   WEST CHILE RISE              

O: 06MAR2019 07:20:45  36.2S   97.5W mw=5.6  ANSS   West Chile Rise"

P:  8MAR2019 114169    36.0S   97.0W 4.0-5.8 AAAAA  Chile Rise                 

 

An M 5.6 also occurred in Papua New Guinea today, the second in that region in as many days. This is the strongest earthquake within about 200 km of this epicenter since an M 6.3 on April 7, 2018, an aftershock of an M 6.7 exactly one year ago on March 6, 2018. Forecast 113942 had expected today's event in this region was likely around March 8. This epicenter is at 143 degrees from the M 7.0 in Peru of March 1. Seismic energy is concentrated at this distance on the surface following major earthquakes after reflection and refraction off inner core boundaries and may help promote regional seismicity. Two earthquakes of M 4.0 and 4.9 off eastern Honshu, Japan today also occurred at this distance from Peru.

 

O:  6MAR2019 18:47:24   4.1S  143.0E Mw=5.6  EMSC   NEW GUINEA, PAPUA NEW GUINEA 

P:  8MAR2019 113942     5.0S  144.0E 4.0-5.5 AAAAA  Papua New Guinea           

 

The strongest earthquake in the U.S. or Canada today was an M 5.2 in northern Alaska. NEIC reported it was felt with intensity II-III in Shungnak and Hualia, Alaska. This is part of a series which has been occurring near this epicenter since late 2018. It is the strongest earthquake within about 200 km of this epicenter since an M 5.3 on October 14, 2018, the only other such event in the area in  at least 30 years. Forecast 114126 had expected this event in this area around March 7. This epicenter is at 102 degrees from the M 7.0 in Peru of March 1 and was probably promoted by strong concentrated energy from that event.

 

 

O:  6MAR2019 22:25:51  66.2N  157.4W ML=3.1  EMSC   NORTHERN ALASKA              

O:  6MAR2019 21:58:32  66.3N  157.2W ML=3.3  EMSC   NORTHERN ALASKA              

O:  6MAR2019 23:21:31  66.3N  157.3W ML=3.0  EMSC   NORTHERN ALASKA              

O:  6MAR2019 21:33:12  66.4N  157.2W Mw=5.2  EMSC   NORTHERN ALASKA              

P:  7MAR2019 114126    65.0N  156.0W 3.0-5.1 ABAAA  Northern Alaska            

 

ANTIPODAL QUAKES IN RAT; BOUVET ISLANDS

 

EARTHQUAKE SUMMARY FOR MARCH 5, 2019

 

A strong M 5.6-5.8 earthquake in the Bouvet Island region of the South Atlantic

was followed by a moderate M 5.1 in the Rat Islands in the antipodal area from the Bouvet epicenter. Antipodal activity in these two areas is not unusual but the strength of these events was. The strongest earthquake in the world, owever, today was an M 5.8-5.9 in Mindanao, Philippines. These may be related to tidal effects from the new moon which arrived today as noted in previous issues of this report:

 

"The new moon will arrive on March 6 at 16:04 UT. Longitudes which are sub-solar at this time are near 60 West and sub-lunar at 120 East. These include the Caribbean and South  America in the west and Taiwan and Indonesia in the east among others. These regions will experience maximum tidal stresses at this time and a moderate to large earthquake near these longitude bands is possible in the next week. Other regions can be triggered by tidal stresses at this time, especially those where fluids are a mitigating factor in seismicity and in areas of vertical tectonics. Tidal triggering often occurs near local solar noon and/or midnight when earth tidal stresses are maximized." (March 3-6, 2019)

 

In particular, the event of M 5.1 in the Rat Islands, Alaska occurred within

about 15 minutes of local solar midnight, a time when tidal forces maximize. This is the strongest event in the Rat Islands within about 250 km of this epicenter since an M 5.1 on February 3, 2019. The last of larger magnitude in the area was an M 6.6 on October 8, 2017.  Forecast 114106 had expected today's event within about 10 km in the Rat Islands most likely around March 3. This earthquake is at 102 degrees from the event of M 7.5 in Ecuador of February 22, and was probably promoted by concentrated energy from that event.

 

O:  5MAR2019 12:01:24  52.0N  175.2E Mw=5.1  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P:  3MAR2019 114106    52.0N  175.0E 4.0-5.6 AAAAA  Rat Islands                

 

The Bouvet Island earthquake of M 5.6-5.8 was not reported felt in this remote area. It is the strongest in that area within about 250 km of today's epicenter since an M i6.5 about 250 km to the northeast of this on December 13, 2017. The last of larger magnitude within about 200 km of today's epicenter was an M 6.4 on June 24, 2007. This area had been expected in forecast 113675 to see a moderate earthquake in mid- to late February. This epicenter is at 102 degrees from the Loyalty Islands where a strong sequence occurred in December 2018 and January, 2019 and was probably promoted from that source. A strong series in Chiapas, Mexico today including an M 4.9 had a similar distance to the Loyalty Islands as did an M 4.4 in Coquimbo, Chile.

 

O:  6MAR2019 05:11:02  55.6S    1.6W mb=5.6  EMSC   BOUVET ISLAND REGION         

O:  6MAR2019 05:11:02  55.5S    1.6W mb=5.8  ANSS   BOUVET ISLAND REGION         

P: 14FEB2019 113675    55.0N    2.0E 3.0-5.1 DABAA  Atlantic-Indian Ridge      

 

The event of M 5.9 in Mindanao, Philippines was probably promoted by tidal effects from the new moon as well. It occurred near the longitude of maximum

stress as noted above in the previously published forecast for this new moon.

BMG reported it was felt with intensity IV in Hinatuan and Bislig City, Surigao Del Sur; III in Lianga, Surigao Del Sur, Butuan City, Nabunturan, Compostela Valley; II in Davao City and I in Cagayan De Oro City, Sta. Cruz, Davao del Sur, Mindanao, Philippines. NEIC reported this earthquake of M 5.7-5.9 in Mindanao, Philippines was felt with intensity II-III in the area(s) of Butuan Caraga and Bogod Eastern Visayas, Philippines. The last earthquake in Mindanao with M>=5.9 occurred on February 8, 2019 and prior to that and M 6.2 on September 8, 2018.

Forecasts 113918 and 113923 had expected today's event was likely around March 6

within about 100 km of this epicenter.

 

O:  6MAR2019 00:13:01   8.6N  127.0E Mw=5.9  EMSC   MINDANAO, PHILIPPINES        

O: 06MAR2019 00:12:55  08.3N  127.3E MS=5.5  BMG  Felt with intensity IV

P:  6MAR2019 113918     9.0N  126.0E 4.0-5.6 AAAAA  Central Philippines        

P: 11MAR2019 113923     8.0N  127.0E 4.0-5.4 BAAAA  Halmahera                  

 

An unusually large earthquake of M 3.4 shook areas of Tennessee today. NEIC reported maximum intensity V in Tennessee at Luttrell; IV in Powder Springs, Maynardville, Washburn, New Tazewell, Sharps, Corryton, Rutledge, amd III in Speedwell and Blaine, Tennessee. This is the strongest earthquake within about 100 km of this epicenter since an M 3.6 on October 12, 2006 and prior to that an M 3.6 on June 17, 1998. An event about 150 km northwest of this last occurred with M 4.4 on December 12, 2018. Foredast 114012 had expected today's event within about 75 km of this epicenter was likely around March 5.

 

O:  5MAR2019 20:56:02  36.3N   83.7W mb=3.6  EMSC   EASTERN TENNESSEE            

P:  5MAR2019 114012    36.0N   83.0W 2.0-4.0 AAAAA  Kentucky/Tennessee/NC      

 

Seismicity also continued to migrate to the south in the Mermadec Island, New Zealand today. This follows several quakes in the area yesterday which were probably promoted by a Tropical Cyclone passing through the region. This had been noted in the previous summary as:

 

 

"The strongest earthquakes in the world today were a pair of events in the Kermadec Islands of northern New Zealand. These events occurred as the remnants of Tropical Cyclone Pola were passing through the region and were probably promoted by stresses associated with TC Pola. This summary had suggest in earlier issues that this was a possibility at this time as:

 

"Tropical cyclone Pola (16F) continued today near the Kermadec Islands with winds up to 50 kts. It could help promote seismicity in the Kermadec - North Island, New Zealand region in the next several days." (March 1-2, 4-5, 2019)

 

Forecast 114175 had expected today's event within about 100 km was likely around March 4. More such activity may occur in the Kermadec Islands with this storm, including the possibility of a strong quake in this active area.

 

O:  6MAR2019 01:47:49  31.8S  178.4W mb=4.9  EMSC   KERMADEC ISLANDS REGION      

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

 

MODERATE EARTHQUAKES IN KERMADEC ISLANDS PROMOTED BY TROPICAL CYCLONE POLA

 

EARTHQUAKE SUMMARY FOR MARCH 3, 2019

 

The strongest earthquakes in the world today were a pair of events in the Kermadec Islamds of northern New Zealand. These events occurred as the remnants of Tropical Cyclone Pola were passing through the region and were probably promoted by stresses associated with TC Pola. This summary had suggest in earlier issues that this was a possibility at this time as:

 

"Tropical cyclone Pola (16F) continued today near the Kermadec Islands with winds up to 50 kts. It could help promote seismicity in the Kermadec - North Island, New Zealand region in the next several days." (March 1-2, 2019)

 

These earthquakes occurred near local solar midnight and noon and may have been promoted by tidal stresses which maximize at this hour. The last earthquake of M>=5.4 in the Central Kermadec Islands within about 200 km of the M 5.4 today occurred July 28, 2018 with M 5.6. Earthquakes of M 5.6 occurred about 200-250 km north of this on November 25, 2018 and October 7, 2018 and a strong M 6.9 occurred about 250 km to the southwest of today's event on September 10, 2018. Forecast 114175 expected today's M 5.4 and 5.0 around March 4. 

 

O:  3MAR2019 10:31:16  30.6S  178.1W Mw=5.4  EMSC   KERMADEC ISLANDS, NEW ZEALAND

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 AAAAA  So. Kermadec Islands       

 

O:  3MAR2019 22:53:24  32.1S  178.1W mb=5.0  EMSC   SOUTH OF KERMADEC ISLANDS    

P:  4MAR2019 114175    31.0S  178.0W 4.0-5.5 ABAAA  So. Kermadec Islands       

 

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Unimak Island area near the Alaska Peninsula. NEIC reported it was felt with intensity II in King Cove, Alaska. This is probably the largest aftershock to date of an M 6.0 of December 31, 2018. Forecast 114111 had expected this event within about 100 km was likely around March 4.

 

O:  4MAR2019 04:51:26  54.6N  161.0W mb=4.8  EMSC   ALASKA PENINSULA             

P:  4MAR2019 114111    54.1N  162.8W 3.5-5.2 AAAAA  Unimak Islands, Aleutians  

 

The most unusual earthquake in the U.S. today was an M 2.5 in Ohio. NEIC reported this earthquake of M 2.5 in Ohio was felt with intensity II-III in the area(s) of Ohio at Greenfield, Postoria and Belle Vernon, Pennsylvania.

No damage was reported with this earthquake. It occurred near local solar midnight and may have been promoted by tidal effects which maximize at this hour. The last earthquake of M>=2.5 within about 100 km of this epicenter was and M 2.8 pm December 17, 2017. An M 2.5 occurred about 250 km northeast of  today's epicenter on January 26, 2018.  Forecasts 114012 and 114080 had expected activity in this area in early March.

 

O:  3MAR2019 06:15:45  38.9N   83.8W Md=2.5  EMSC   OHIO                          

P:  4MAR2019 114012    37.2N   81.9W 2.0-4.3 ABBAA  Kentucky/Tennessee/NC      

P: 11MAR2019 114080    40.0N   84.0W 2.0-3.9 CBAAA  Ohio/Lake Erie             

 

<ODERATE SEISMICITY MIGRATES FROM GEOMAGNETIC EQUATOR

 

EARTHQUAKE SUMMARY FOR MARCH 2, 2019

 

The current geomagnetic storm continued today but at a reduced level. Normally after the initiation of a strong geomagnetic storm, The largest of these were an M 5.6 in the Valparaiso area of Chile about 15 degrees south of the geomagnetic equator and an M 5.5 in northern Philippines about 10 degrees north of the geomagnetic equator. After geomagnetic storms ionospheric ring currents form about 10-15 degrees from the geomagnetic equator and induce telluric currents in the earth below. These may be partially responsible for triggering seismicity in these areas.

 

The earthquake of M 5.5 in the area off the coast of Valparaiso, Chile was the first of M>=5.5 within about 150 km of this epicenter since an M 5.5 on December 5, 2018. the last of larger magnitude was an M 6.9 on April 24, 2017. Forecast 114167 had expected today's quake to the southeast was likely around March 4. No major damage was reported with this earthquake.

 

CSN reported this earthquake was felt with intensity   IV in  Valparaiso at Quillota, San Felipe and Villa Alemana; III in Casablanca, Olmue, Quilpue, Vina Del Mar and II in Algarrobo; in Santiago at Tiltil with III, Chile. NEIC reported this earthquake of M 5.5 offshore Valparaiso, Chile  was felt with intensity V in Vina Del Mar, Valparsiao; IV in Valparaiso  and II-III in the area(s) of Curico and San Felipe, Chile.

 

O:  2MAR2019 20:21:51  33.7S   72.5W Mw=5.5  EMSC   OFFSHORE VALPARAISO, CHILE    

O:  2MAR2019 07:57:40  33.7S   72.5W mb=4.5  EMSC   OFFSHORE VALPARAISO, CHILE   

O:  2MAR2019 20:21     33.7S   72.5W mb=5.5  GUC    Valparaiso at Quillota, San Fe

P:  4MAR2019 114167    35.0S   71.0W 4.0-5.6 ABAAA  Central Chile              

 

The M 5.6 in the Northern Philippines in Luzon Island was also not damaging

in the area.  PHIVOLCS reported this earthquake was felt with intensity V in Burgos, Ilocos Norte; IV in Dingras, Paoay Bacarra, San Nicolas, Pasuquin and Laoag City; Ilocus Norte, sinait and Cabugao, Ilocos Sur; III in Badoc, Ilocos Norte; Santa Sta. Catalina, Bantay Magsingal, San ldafonso and Santo Domingo, Ilocos Sur and II in Aparri, Cagayan, Caoayan, Sta. Lucia, Sugpon, Gregorio del Pitar, Ilocos Sur, Philippines. NEIC reported this earthquake of M 5.6 in Northern Luzon, Philippines was felt with intensity V in Pacay, Ilocos, and II-III in the area(s) of the Philipines at Pasuquin, Pagudpud Bacarra, Ilocos, San Nicolas, Nagbacalan, Sinait and Tuding, Philippines. It is the strongest earthquake within about 150 km of this epicenter since an M 5.6 on March 12, 2016. The last of larger magnitude in the area was an M 5.8 on February 17, 2014. Forecasts 113964 and 113721 had expected this event within about 100 km was likely in late February or early March.

 

O:  2MAR2019 19:46:24  18.5N  120.6E Mw=5.6  EMSC   LUZON, PHILIPPINES           

O: 02MAR2019 19:46:22  18.6N  120.4E MS=5.3  PHI  Felt with intensity V

P:  3MAR2019 113964    19.0N  120.0E 3.5-4.9 AAAAA  Luzon, Philippines          

P: 26FEB2019 113721    19.0N  121.0E 3.5-4.9 BAAAA  Luzon, Philippines         

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 in the central Andreanof Islands, Aleutians, Alaska. It was not reported felt in this remote region. This is the strongest earthquake within about 150 km of this epicenter since an M 4.7 on November 21, 2018. Earthquakes of M 4.4-4.5 have since occurred about 150 km west of this on November 30, 2018 and February 10, 2019. Forecast 113836 had expected this event was likely at the end of February.

 

O:  3MAR2019 01:07:20  52.7N  174.4W mb=4.2  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 27FEB2019 113836    52.3N  174.6W 3.5-4.9 BAAAA  Andreanoff Isls, Aleutians 

 

A pair of earthquakes off the coast of central America of M 2.0 and 2.2 occurred today. Occasionally earthquakes in this area precede stronger earthquake in the San Andreas Fault zone to the east by several days to a week. The last event within about 50 km of the M 2.2 epicenter with equal or greater magnitude occurred August 21, 2018 with M 2.4. Forecast 114025 had expected activity in early March about 50 km to the southeast.

 

O:  2MAR2019 15:12:34  36.7N  122.0W Md=2.2  EMSC   OFFSHORE CENTRAL CALIFORNIA  

O:  2MAR2019 20:56:03  36.2N  121.8W Md=2.0  EMSC   OFFSHORE CENTRAL CALIFORNIA  

P:  6MAR2019 114025    35.7N  121.2W 2.5-4.5 BAAAA  Off So. California         

 

 

GEOMAGNETIC STORM, ACTIVE SEISMICITY CONTINUE

 

EARTHQUAKE SUMMARY FOR MARCH 1, 2019

 

The geomagnetic storm which began February 28 continued through March 1. It was accompanied by active seismicity including an M 7.0 on the Geomagnetic Equator in central Peru and an M 6.0 in Hokkaido, Japan. The  geomagnetic storm was described in the previous issue of this summary as:

 

 

"The geomagnetic field saw active conditions today. The AP level was 26. High latitude geomagnetic field saw minor storm conditions  with AP at 34. This is the strongest global geomagnetic storm since AP reached 35 on November 5, 2018.

At high latitudes A reached 40 on February 1. This storm is likely to promote moderate to strong seismicity along the geomagnetic equator and to a lesser extent at high latitudes. The storm reached maximum levels early on February 28 and would most likely affect seismicity in the Caribbean and western south America where a moderate to strong earthquake could occur in the next several days." (March 1, 2019)

 

The strongest earthquake of the day was a major event of M 7.0 in eastern Peru. This event occurred at a depth of 257 km and was widely felt throughout the region but with only minor damage due to the depth. NEIC reported maximum shaking of V in Iquique, Tarapaca Chile, 665 km from the epicenter and in Tacna, Peru at 450 km from the epicenter. CSN reported this earthquake was felt with intensity VII in  Arica and Parinacota at Arica and Poconchile and VI in Codpa and Cuya; in Tarapaca with V in Alto Hospicio, Huara, Iquique, La Tirana, Mamina, Pica, Pisagua, Pozo Almonte and in Antofagasta with IV in Calama, Maria Elena, Quillagua and Tocopilla, Chile. IGP reported it was felt with intensity V in  San Anton, Sandia, Huatahuasi, Huancane, Peru. The earthquake of M 7.0 in Peru today on the geomagnetic equator occurred at the peak of this storm. Intensity IV was reported from Arica, Chile, and in Peru at Puno, Arequipa, Anta Cusco, Moquegua, with lesser shaking of II-III in Chile at Calama, Antofagasta, in Bolivia at Sucre and Cochabamba and El Alto La Paz, La Paz and in Peru at Chiva, Arequipa, Oropesa, Cusco,  Ilabaya, Mollendo, Santa Ana, Ilo Moquigua.

As the epicenter is directly on the geomagnetic equator, it was almost certainly promoted by geomagnetic effects associated with this storm.

 

The last earthquake within about 250 km of today's Peru epicenter with M>=7.0 occurred more than 30 years ago. An M 8.2 occurred about 350 km northeast of this on June 9, 1994. That earthquake occurred at 631 km depth and was the most widely felt earthquake in recent history being felt as far as Canada. An M 7.0 on July 6, 1991 at 104 km depth occurred about 350 km to the northwest of today's epicenter. Forecasts 113879, 113630 and 113872 had expected this activity at the end of February was likely within about 100 km of today's epicenter.

 

O:  1MAR2019 08:50:44  14.8S   70.1W Mw=7.0  EMSC   SOUTHERN PERU                

O: 01MAR2019 08:50:41  14.7S   70.1W mw=7.0  ANSS   NNE of Azangaro Peru

O:  1MAR2019 08:50     14.7S   70.4W mb=7.0  GUC    Arica and Parinacota at Arica

O:  1MAR2019 08:50     14.8S   70.2W mb=7.0  IGP    San Anton, Sandia, Huatahuasi,

P: 27FEB2019 113879    16.0S   71.0W 4.0-5.9 ABAAA  So. Peru/Bolivia           

P: 20FEB2019 113630    15.0S   71.0W 4.0-5.6 CAAAA  Central Peru               

P: 23FEB2019 113872    14.0S   73.0W 4.0-5.6 CABAA  Central Peru               

 

A strong earthquake of M 6.0 also occurred east of Hokkaido, Japan today. NEIC reported it was felt with intensity II-III in Hokkaido at Shibetsu, Rurano, Sapporo, and in Aomori at Hachinohe and Misawa. This is an unusual epicenter and may be an outer rise quake. Outer rise earthquakes occur when the subducting plate is compressed, usually due to an obstruction. They have been associated on occasion with large earthquake down slope shortly afterwards. The last earthquake within about 250 km of this epicenter off Hokkaido with M>=6 was an M 6.8 on December 6, 2004. The only other such earthquake in this area in the past 30 years was an M 6.0 on March 31, 1990. Forecast 113804 had expected this activity about 200 km north of today's epicenter was likely around February 27.

 

O:  2MAR2019 03:22:52  41.9N  147.0E Mw=6.0  EMSC   OFF COAST OF HOKKAIDO, JAPAN 

P: 27FEB2019 113804    44.0N  147.0E 3.5-5.4 ACAAA  Hokkaido, Japan            

 

The strongest earthquake felt in the U.S. or Canada today occurred as an M 3.8 off the coast of Northern California. NEIC reported it was widely felt along the coast with intensity II-III reported from Petrolia, Ferndale, Rio Dell, Scotia, Fortuna, Myers Flat, Whitethorn, Redcrest, Carlotta, Garberville, Eureka, Alderpoint and Bridgeville, California. The last earthquake of M>=3.9 within about 50 km of this epicenter was an M 4.1 on February 3, 2019. Forecast 113817 had expected this event within about 25 km was likely around February 28.

 

O:  2MAR2019 05:55:56  40.3N  124.5W mb=3.9  EMSC   OFFSHORE NORTHERN CALIFORNIA 

P: 28FEB2019 113817    40.2N  124.2W 2.5-4.5 AAAAA  Off Coast of No. Calif     

 

The strongest earthquake in the U.S. or Canada which was not felt was an M 4.2 in the Near Islands, near the western most part of the U.S, The last event of M>=4.2 in the Near Islands occurred on October 26, 2018 with M 4.6. Forecast 113842 had expected activity to the west of this at the end of February. This epicenter is located at the third node (120 degrees) from the earthquake in Peru and may have been promoted by energy from that source.

 

O:  1MAR2019 19:47:57  53.9N  170.6E mb=4.2  EMSC   NEAR ISLANDS, ALEUTIAN ISLANDS

P: 25FEB2019 113842    55.0N  164.0E 4.0-5.8 BBBAA  Komandorsky Isl            

 

GEOMAGNETIC STORM BRINGS ACTIVE SEISMICITY BACK

 

EARTHQUAKE SUMMARY FOR FEBRUARY 28, 2019

 

The geomagnetic field saw active conditions today. The AP level was 26. High latitude geomagnetic field saw minor storm conditions  with AP at 34. This is the strongest global geomagnetic storm since AP reached 35 on November 5, 2018.

At high latitudes A reached 40 on February 1. This storm is likely to promote moderate to strong seismicity along the geomagnetic equator and to a lesser extent at high latitudes. The storm reached maximum levels early on February 28 and would most likely affect seismicity in the Caribbean and western south America where a moderate to strong earthquake could occur in the next several days.

 

A near-antipodal group of earthquakes in the Macquarie Ridge south of New Zealand Iceland and the Reykjanes Ridge in the Northern Mid-Atlantic today included the largest earthquake in the world today - the M 5.8 in the Macquarie Ridge. These events at high latitudes may have been promoted by the geomagnetic storm which was active when they occurred. An M 4.4 north of the Reykjanes Ridge and Iceland  was part of this antipodal group. Antipodal high- or low- latitude antipodal activity is not uncommon with unusually strong geomagnetic storms.

 

The earthquake in the Macquarie Ridge of M 5.8 is the largest located within  about 300 km of this epicenter since an M 6.1 about 200 km southwest of this on September 8, 2016 and prior to that an M 5.8 on June 22, 2012.

 

 

O:  1MAR2019 01:02:12  53.4S  159.7E Mw=5.8  EMSC   MACQUARIE ISLAND REGION      

 

The M 4.5 in the Reykjanes Ridge - nearly antipodal to the Macquarie Island area was the largest within about 200 km of that epicenter since an M 4.5 on December 30, 2018.  Forecast 113844 expected today's activity in this region within about 100 km of this epicenter was likely around February 26.

 

O: 28FEB2019 12:35:14  56.7N   34.5W mb=4.5  EMSC   REYKJANES RIDGE              

P: 26FEB2019 113844    57.0N   33.0W 4.0-5.6 AAAAA  North Mid-Atlantic Ridge   

 

The two earthquakes of M 4.4 in Iceland had been expected in that area around February 25. They are the strongest within about 200 km of that epicenter in more than a year - since an M 5.0 on February 19, 2018.

 

O: 28FEB2019 07:37:26  67.7N   19.0W mb=4.4  EMSC   ICELAND REGION               

O: 28FEB2019 07:43:11  67.9N   18.9W mb=4.4  EMSC   ICELAND REGION               

P: 25FEB2019 113860    65.0N   17.0W 3.0-4.7 BCAAA  Iceland area               

 

An unusually large earthquake in South Africa of M 4.7 was also associated

today with the strongest portions of the current geomagnetic storm. This is the strongest earthquake in South Africa since an M 5.2 on April 3, 2017 and prior to that an M 5.3 on August 5, 2014.  but was not reported felt. Forecast 113653 had expected this event within about 50 km of the epicenter was likely in late February. This earthquake is located at 102 degrees from the last major earthquakes in the world - the M 7.6 in Ecuador of February 22 and the Molucca Sea event of December 29, 2018 and was probably promoted by strong concentrations of energy at this distance from these  earthquakes.

 

O:  1MAR2019 04:56:46  26.3S   27.7E mb=4.7  EMSC   SOUTH AFRICA                 

P: 21FEB2019 113653    26.0S   28.0E 3.0-4.4 CAAAA  Rep. South Africa          

 

An earthquake of M 5.5 also occurred deep under Santiago Del Estero, Argentina today. It was not reported felt on the surface. This is the strongest earthquake in this area since an M 5.6 on July 20, 2018. Forecast 113884 had expected a moderate quake in Argentina north of this epicenter at the end of February.

 

O:  1MAR2019 00:13:28  28.3S   63.3W Mw=5.5  EMSC   SANTIAGO DEL ESTERO, ARGENTINA

P: 27FEB2019 113884    24.0S   64.0W 4.0-5.8 ACAAA  Argentina                  

 

An M 5.3 in Sumatra, Indonesia today may have been promoted by the M 7.6 on  February 22 in the region of Ecuador which is nearly antipodal to the Sumatra epicenter. This appears to be an aftershock of the M 5.4-5.6 in Sumatra which was reported on in this summary in the previous issue as:

 

 

"A pair of moderate earthquakes in  northern Sumatra occurred several hours after the mainshock in Ecuador. These are located near the antipode of that event and may have been promoted by concentrated antipodal energy from Ecuador.

The true antipode is at 2N 103E, north and east of the active seismic regions in Sumatra. But some triggering is likely in Sumatra in coming days." (February 22-23, 2019)

 

BMG reported the M 4.8 was felt with intensity II-III in Solok Selatan, Sumatra, Indonesia. The M 5.6 was felt with intensity IV in Solok Selatan, III-IV in Padang; II-III in Painan, Padang Panjang and II in Muaro Siberut, Mukomuko, Bukittinggi,  Sumatra, Payakumbuh and Kepahiang, Indonesia. NEIC reported this earthquake of M 5.4 in Southern Sumatra was felt with intensity II-III in the area(s) of Sungaipenuh, Jambi, Padang, Sumatra and possibly in Singapore. The last earthquake of M>=5.4 within about 150 km of this epicenter was an M 6.0 on May 15, 2015. Forecast 113706 had expected moderate activity south of Sumatral at the end of February. In addition to being at the antipode to Ecuador this epicenter is also at 101 degrees from the Anchorage, Alaska quake of November 30, 2018 (M 7.1) and may have been promoted by concentrated energy from that source." (February 28, 2019)

 

BMG reported this earthquake was felt with intensity III-IV in Mentawai and Painan; II-III in Padang and I-II in Padang Panjang, Solok, Bukittinggi, Sumatra, Indonesia.

 

O: 28FEB2019 14:18:53   2.1S  100.0E mb=5.3  EMSC   EP. MENTAWAI REGION, INDONESIA

O: 28FEB2019 14:18:53  02.1S  099.8E MS=5.1  BMG  Felt with intensity III-IV

P: 24FEB2019 113706     2.0S   99.0E 4.0-5.5 BAAAA  So. of Sumatera            

 

The largest earthquake in the U.S. or Canada today was an M 4.2 in the aftershocks region of the Gulf of Alaska. Aftershocks of this size are common in this aftershock sequence with five in 1919. The last was an M 4.4 on February 23, 2019.

 

O:  1MAR2019 05:20:58  56.3N  148.7W ML=3.3  EMSC   GULF OF ALASKA                

O:  1MAR2019 03:41:00  56.4N  148.7W mb=4.2  EMSC   GULF OF ALASKA               

 

The largest earthquake in the U.S. outside Alaska was an M 3.6 in the Alamosa area of Colorado. This is part of a series which included and M 3.8 yesterday. In the previous issue this summary noted:

 

"An unusually large earthquake of M 3.8 occurred in southern Colorado today. NEIC reported it was felt with maximum intensity IV in Hooper and Alamosa, Colorado with lighter shaking of II-III reported from Mosca, Moffat, Monte Vista, Westcliffe, Rye, Antonito, Baguache and Fountain, Colorado.  This was the largest earthquake in the U.S. or Canada today. It was associated with several smaller foreshocks of M 2.4 and 1.9. This appears to be a part of the activation of the Rocky Mountain region which began about a week ago with quakes in Montana and Utah, The last earthquake of M>=3.8 within about 100 km of this epicenter in Colorado was an M 4.0 in the Trinidad swarm about 100 km southeast of this epicenter. The Trinidad events have been ongoing since September 2001. No earthquakes of this size or larger have been recorded in the past 30 years within 75 km of today's epicenter, making this an important regional event. Forecast 113761 had expected this earthquake was likely around February 28." (February 28, 2019)

 

NEIC reported the earthquake of M 3.6 in Colorado was felt with intensity II-III in the area(s) of Colorado at Mosca, Fort Garland, Moffat, Westcliffe, Rye, Colorado Springs, and Golden.

 

O: 28FEB2019 15:33:54  37.6N  105.5W ML=3.6  EMSC   COLORADO                     

O: 28FEB2019 17:21:20  37.7N  105.4W ml=1.2  ANSS   Alamosa East Colorado

O: 28FEB2019 10:03:51  37.7N  105.5W ml=1.5  ANSS   Alamosa East Colorado

O: 28FEB2019 09:41:23  37.7N  105.5W ml=0.9  ANSS   Alamosa East Colorado

O: 28FEB2019 09:16:58  37.7N  105.5W ml=1.3  ANSS   Alamosa East Colorado

P: 28FEB2019 113761    38.3N  108.9W 2.0-4.0 AABAA  Colorado area              

 

STRONG QUAKE IN SUMATRA ANTIPODAL TO ECUADOR; UNUSUAL M 3.8 IN COLORADO

 

EARTHQUAKE SUMMARY FOR FEBRUARY 27, 2019

 

The strongest earthquake in the world today was an  M 5.4-5.6 in Sumatra, Indonesia. This epicenter is nearly antipodal to the M 7.6 in Ecuador of February 22. At that time this summary had warned of possibly enhanced seismicity in Sumatra as:

 

"A pair of moderate earthquakes in  northern Sumatra occurred several hours after the mainshock in Ecuador. These are located near the antipode of that event and may have been promoted by concentrated antipodal energy from Ecuador. The true antipode is at 2N 103E, north and east of the active seismic regions in Sumatra. But some triggering is likely in Sumatra in coming days." (February 22-23, 2019)

 

BMG reported the M 4.8 was felt with intensity II-III in Solok Selatan, Sumatra, Indonesia. The M 5.6 was felt with intensity IV in Solok Selatan, III-IV in Padang; II-III in Painan, Padang Panjang and II in Muaro Siberut, Mukomuko, Bukittinggi,  Sumatra, Payakumbuh and Kepahiang, Indonesia.

NEIC reported this earthquake of M 5.4 in Southern Sumatra was felt with intensity II-III in the area(s) of Sungaipenuh, Jambi, Padang, Sumatra and possibly in Singapore. The last earthquake of M>=5.4 within about 150 km of this epicenter was an M 6.0 on May 15, 2015. Forecast 113706 had expected moderate activity south of Sumatra at the end of February. In addition to being at the antipode to Ecuador this epicenter is also at 101 degrees from the Anchorage, Alaska quake of November 30, 2018 (M 7.1) and may have been promoted by concentrated energy from that source.

 

O: 27FEB2019 23:27:04   1.3S  101.6E Mw=5.4  EMSC   SOUTHERN SUMATRA, INDONESIA  

O: 27FEB2019 19:44:12   1.4S  101.5E ML=4.1  EMSC   SOUTHERN SUMATRA, INDONESIA  

O: 27FEB2019 18:54:57   1.5S  101.6E ML=4.8  EMSC   SOUTHERN SUMATRA, INDONESIA  

O: 27FEB2019 18:55:02  01.6S  101.3E MS=4.8  BMG  Felt with intensity II-III

O: 28FEB2019 23:27:05  01.4S  101.6E MS=5.6  BMG  Felt with intensity IV

P: 25FEB2019 113706     4.0S  102.0E 4.0-5.4 ACAAA  So. of Sumatera            

 

An unusually large earthquake of M 3.8 occurred in southern Colorado today. NEIC reported it was felt with maximum intensity IV in Hooper and Alamosa, Colorado with lighter shaking of II-III reported from Mosca, Moffat, Monte Vista, Westcliffe, Rye, Antonito, Baguache and Fountain, Colorado.  This was the largest earthquake in the U.S. or Canada today. It was associated with several smaller foreshocks of M 2.4 and 1.9. This appears to be a part of the activation of the Rocky Mountain region which began about a week ago with quakes in Montana and Utah, The last earthquake of  M>=3.8 within about 100 km of this epicenter in Colorado was an M 4.0 in the  Trinidad swarm about 100 km southeast of this epicenter. The Trinidad events have been ongoing since September 2001. No earthquakes of this size or larger have been recorded in the past 30 years within 75 km of today's epicenter, making this an important regional event. Forecast 113761 had expected this earthquake was likely around February 28.

 

O: 28FEB2019 03:38:56  37.6N  105.6W ML=3.8  EMSC   COLORADO                     

O: 27FEB2019 19:04:15  37.6N  105.6W ml=1.9  ANSS   Alamosa East Colorado

O: 27FEB2019 17:10:21  37.6N  105.5W ml=2.4  ANSS   Alamosa East Colorado

O: 27FEB2019 17:10:21  37.7N  105.5W ML=2.4  EMSC   COLORADO                     

P: 28FEB2019 113761    38.3N  108.9W 2.0-4.0 AACAA  Colorado area              

 

UNUSUAL LIGHT EARTHQUAKE SHAKES SOUTHEAST ENGLAND

 

EARTHQUAKE SUMMARY FOR FEBRUARY 26, 2019

 

An unusual earthquake of M 3.6 shook parts of England including London today, NEIC reported this earthquake of M 3.3 in England was felt with intensity IV in Salfords, Crawley, and II-III in the area(s) of England at Portsmouth, London, East Grinstead, Horham, Reigate, Reigate-Redhill and Dorking.   This is an unusually large event for the region of southeastern England, the first of it's magnitude or greater within about 100 km of this epicenter since an M 5.0 on April 28, 2007. The last within about 250 km was an M 4.0 on June 9, 2018 about 250 km north of today's epicenter. Forecast 114608 had expected this activity in southern England around February 18.

 

O: 27FEB2019 03:42:21  51.0N    0.3W ML=3.6  EMSC   ENGLAND, UNITED KINGDOM      

P: 18FEB2019 113608    51.0N    3.0W 3.0-4.5 CABAA  United Kingdom             

 

An M 3.1 in Los Angeles, California today was widely felt in the city. NEIC reported light to moderate shaking with intensity II-III in Norwalk, Artesia, Cerritos, Bellflower, Downey, Santa Fe Springs, Lakewood and in general within about 100 km of the epicenter. This is the second light earthquake in the area in as many days. When an M 2.6 occurred here yesterday, this summary noted:

 

 

"The largest earthquake in California today occurred as an M 2.5 in the Channel Islands region of California today. NEIC reported this earthquake of M 2.6 in Southern California was felt with intensity II-III in the area(s) of California at Marina and Los Angeles. This is an area which is at the seventh node from the M 7.6 in Ecuador several days ago (52 degrees). Earthquakes in southern California may be enhanced by energy from that event as noted in previous issues of this report.

 

"Earthquakes of this size in Ecuador can help promote seismicity in California several months later. This summary will follow this in future issues." (February 22-23, 26, 2019)

 

The last earthquake within about 50 km of today's epicenter with M>=3.1 was an

M 3.1 on November 10, 2017. The last of larger magnitude wasn an M 3.7 on October 26, 2017.   Forecast 113786 had expected today's event within about 20 km was likely around February 25.

 

O: 26FEB2019 09:51:34  33.9N  118.1W Ml=3.1  EMSC   GREATER LOS ANGELES AREA, CALI

P: 25FEB2019 113786    33.9N  118.3W 2.5-4.5 AAAAA  So. California             

 

The strongest earthquakes of the day occurred as an M 5.1 in the Southern East Pacific Rise and an M 5.0 in the South Sandwich Islands. Both were not felt but occurred in the same general region of the southern Oceans. The earthquake on the East Pacific Rise is the largest within about 250 km of that epicenter since an M 5,1 on November 27, 2016. The last event in the region of larger magnitude was an M 5.4 on September 9, 2015.

 

 

O: 27FEB2019 02:44:32  49.6S  116.3W mb=5.1  EMSC   SOUTHERN EAST PACIFIC RISE   

 

The earthquake in the South Sandwich Islands of M 5.0 occurred to the east of

the typical activity in the area by about 150 km.

The last event within this area with M>=5 was an M 5.1 on October 9, 2015. Forecast 113914 had anticipated the South Sandwich Islands could see a moderate earthquake around February 27.

 

O: 27FEB2019 06:28:14  57.4S   23.6W mb=5.0  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 27FEB2019 113914    59.0S   26.0W 4.0-5.8 ABBAA  So. Sandwich Islands       

 

A moderate earthquake in the region south of Fiji today of M 4.9 may have been promoted by Tropical Cyclone Pola. This summary had noted this possibility in previous issues as:

 

"Tropical cyclone Pola (16F) continued today near Tonga with winds up to 80 kts. It is expected to track to the south reaching Tonga around February 27. It could help promote seismicity in the Samoa-Tonga region in the next several days." (February 25-27, 2019)

 

Forecast 113894 had expected this event within about 50 km was likely around February 23. This epicenter is at 101 degrees from the M 7.6 in Ecuador of February 22 and may have been promoted by concentrated energy from that event.

 

O: 27FEB2019 02:00:02  22.1S  179.5W mb=4.9  EMSC   SOUTH OF FIJI ISLANDS        

P: 23FEB2019 113894    22.0S  180.0W 4.0-5.7 BAAAA  Tonga Islands              

 

M

UNUSUAL EARTHQUAKE IN THE CENTRAL MID-ATLANTIC

 

EARTHQUAKE SUMMARY FOR FEBRUARY 25, 2019

 

The strongest earthquake of the day was an M 5.5-5.6 in the Central Mid-Atlantic Ridge. It was followed by an M 4.9 aftershock. Neither were felt in this remote area of the Atlantic. The mainshock occurred within about an hour of local solar noon and may have been promoted by tidal effects which maximize at this hour. The last earthquake within about 250 km of this epicenter in the Central Atlantic with M>=5.5 was and M 5.5 on February 27, 2016. The last of M>5.6 occurred as an M 5.8 on August 2, 2010. Forecast 113678 had expected the central mid-Atlantic to be active around February 24.

 

 

O: 25FEB2019 15:05:33   4.3N   32.7W Mw=5.5  EMSC   CENTRAL MID-ATLANTIC RIDGE   

O: 25FEB2019 15:05:33   4.3N   32.6W Mw=5.6  ANSS   CENTRAL MID-ATLANTIC RIDGE   

O: 25FEB2019 15:47:33   4.3N   32.8W mb=4.9  EMSC   CENTRAL MID-ATLANTIC RIDGE   

P: 24FEB2019 113678     1.0N   28.0W 4.0-5.5 ACCAA  Central Mid-Atlantic Ridg  

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 in Northern Alaska. It was not reported felt in the epicentral area. The last earthquake of M>=4.1 within about 150 km of this epicenter was an M 4.8 on February 10, 2019 and prior to that an M 4.5 on March 22, 2010. It is probably the largest aftershock of the February 10 mainshock. Forecast 113859 had expected this event was likely in this area around February 28.

 

 

O: 26FEB2019 04:09:41  66.3N  157.3W ml=4.1  EMSC   NORTHERN ALASKA              

P: 28FEB2019 113859    65.3N  157.5W 3.2-4.9 AAAAA  Northern Alaska            

 

The largest earthquake in California today occurred as an M 2.5 in the Channel Islands region of California today. NEIC reported this earthquake of M 2.6 in Southern California was felt with intensity II-III in the area(s) of California at Marina and Los Angeles. This is an area which is at the seventh node from the M 7.6 in Ecuador several days ago (52 degrees). Earthquakes in southern California may be enhanced by energy from that event as noted in previous issues of this report.

 

"Earthquakes of this size in Ecuador can help promote seismicity in California several months later. This summary will follow this in future issues." (February 22-23, 2019)

 

The last earthquake within about 50 km of this epicenter in the Channel Islands occurred on February 23, 2019 with M 2.6 and prior to that an M 2.6 on August 5, 2018. Forecast 113786 had expected this earthquake was likely in this area around February 25. The earthquake of February followed the Ecuador mainshock by about a day.

 

O: 25FEB2019 21:25:34  33.4N  118.4W Ml=2.5  EMSC   CHANNEL ISLANDS, CALIFORNIA  

P: 25FEB2019 113786    33.9N  118.3W 2.5-4.5 AAAAA  So. California             

 

ODERATE EARTHQUAKES IN SOUTHWEST PACIFIC

 

EARTHQUAKE SUMMARY FOR FEBRUARY 24, 2019

 

With the geomagnetic storm ending and no major meteorological storms in seismic areas, global seismicity was at low levels. The largest earthquakes of the day were unremarkable events of M 5.1 in Vanuatu; M 5.0 in Minahasa, Indonesia and an M 5.0 in New Britain. These were not reported felt in their respective epicentral areas with the exception of the M 5.0 in Minahasa. These may have been promoted by residual effects from the previous geomagnetic storm three days ago.

 

O: 25FEB2019 05:01:17   4.5S  151.8E mb=5.0  EMSC   NEW BRITAIN REGION, P.N.G.   

P: 27FEB2019 113696     5.0S  152.0E 4.0-5.5 AAAAA  New Britain                

 

O: 24FEB2019 19:50:19  10.6S  165.8E mb=5.1  EMSC   SANTA CRUZ ISLANDS           

P: 19FEB2019 113644    13.0S  166.0E 4.0-5.4 BCAAA  Vanuatu Islands            

 

O: 24FEB2019 13:29:33   0.5N  122.2E Mw=5.1  EMSC   MINAHASA, SULAWESI, INDONESIA

P: 27FEB2019 113677     1.0N  122.0E 4.0-5.4 BAAAA  Celebes Sea                

 

The strongest earthquake in the U.S. or Canada today was an M 4.2 off the coast of northern California. NEIC reported this earthquake of M 4.2 Off Northern California was felt with intensity II-III in the area(s) of Eureka, California.  The last earthquake in this area with M>=4.2 was an M 4.5 on July 25, 2018.  Forecast 113817 had expected today's event was likely to occur within about 25 km  of this epicenter around February 22.

 

O: 24FEB2019 20:54:41  40.3N  125.2W ML=3.0  EMSC   OFFSHORE NORTHERN CALIFORNIA 

O: 24FEB2019 21:05:11  40.4N  125.0W Mw=4.2  EMSC   OFFSHORE NORTHERN CALIFORNIA 

P: 22FEB2019 113817    40.6N  124.9W 2.5-4.8 AAAAA  Off Coast of No. Calif     

 

The strongest earthquakes in Alaska today were a pair of events of M 3.1 in the Anchorage, Alaska aftershock zone. This is not unusual activity and M 3's in the area are an almost daily event. Forecast 113855 had expected today's activity was likely around February 26.

 

NEIC reported these earthquakes of M 3.1 in the Anchorage, Alaska aftershock zone was felt with intensity II-III in the area(s) of Anchorage, Chugiak, Willow, and Eagle River, Alaska.

 

O: 25FEB2019 05:39:52  61.4N  150.1W ml=3.1  EMSC   SOUTHERN ALASKA              

O: 24FEB2019 16:37:36  61.7N  150.0W ML=3.1  EMSC   SOUTHERN ALASKA              

P: 26FEB2019 113855    61.1N  149.9W 3.2-4.9 AAAAA  Central Alaska             

 

NEAR-ANTIPODAL QUAKES IN MACQUARIE ISLANDS; ICELAND

 

EARTHQUAKE SUMMARY FOR FEBRUARY 23, 2019

 

The two most unusual earthquakes in the world today occurred in zones which are nearly antipodal. These included the largest quake of the day - an M 5.5 in the Macquarie Island region south of Australia and New Zealand and an unusually large earthquake of M 4.5 northeast of Iceland. These are at high latitudes and could have been promoted by the recent geomagnetic storm but could also be coincidental. Neither of these events were reported felt in the epicentral areas.   The earthquake in the Macquarie Island area is the strongest within about 250 km of that epicenter since an M 5.7 on June 16, 2013 and prior to that an M 5.9 on February 9, 2012.

 

O: 24FEB2019 06:00:31  57.7S  157.7E mb=5.5  EMSC   MACQUARIE ISLAND REGION      

 

The event in Iceland of M 4.5 is the largest within about 250 km of that epicenters since an M 4.7 on December 28, 2018.   Forecast 113617 had expected activity in the Iceland area in mid-February.

 

O: 23FEB2019 21:24:01  64.6N   17.3W mb=4.5  EMSC   ICELAND                      

O: 24FEB2019 03:30:58  66.8N   18.5W ML=3.1  EMSC   ICELAND REGION               

P: 17FEB2019 113617    63.0N   26.0W 3.0-4.4 CBCAA  Iceland Region             

 

The strongest earthquake in the U.S. or Canada today was an M 4.0 in the Unimak Island area of Alaska. It was not reported felt in this remote area. A strong M 6.0 hit the area of the Unimak Island on December 31, 2018 and was followed by an M 5.1 on February 15, 2019, the only recent events of M>=4 in the Unimak area. Forecast 113607 had expected this activity in the Unimak area was likely in mid-February.

 

O: 24FEB2019 05:07:51  53.4N  163.6W mb=4.0  EMSC   UNIMAK ISLAND REGION, ALASKA 

P: 19FEB2019 113607    54.2N  165.0W 3.5-5.2 BAAAA  Unimak Islands, Aleutians  

P: 21FEB2019 113607    54.3N  161.4W 3.5-5.1 BABAA  Unimak Islands, Aleutians  

 

MAJOR EARTHQUAKE ROCKS ECUADOR AND PERU

 

EARTHQUAKE SUMMARY FOR FEBRUARY 22, 2019

 

A major earthquake of M 7.5 (EMSC) to 7.7 (IGP) hit the coast of Ecuador today. It occurred at an intermediate depth of 132 km and was felt with moderate intensity throughout much of Ecuador. NEIC reported maximum intensity V-VII in Ecuador was felt at Gualaceo, Azuay, Guayaquil, Loja, Eloy Alfaro, Puebloviejo (VI), La Troncal, Azogues (VII), Gualaceo,  Ecuador in Peru at Piura, Tarapoto, Iquitos, Jaen, Yunmaguas, Tumbes (VII), and with intensity VI in Ecuador at Puyo Pastaca, Banos, Tungurahua, Ambato, Cuenca, Zamora, Santa Lucia, Machala, Playas Guayas, Portoviejo, Manta, Salinas and in Peru at Moyobamba, Colan, Huanchanco, and in general within about 1000 km from the epicenter. IGP reported intensity V in Pastaza with an aftershock of M 5.7 felt with III in Zarumilla, Peru. Some damage was reported. News sources on the web reported  NEIC reported this aftershock at M 5.5 was felt in Ecuador with intensity V in Guayaquil, and Santa Lucia, and II-III in Ecuador at Eloy Alfara, Guayas, Cuenca Azuay, Machala, Pajan, Santa Elena, Montecristi, Banos and Manta, Ecuador. no injuries associated with the quake. This was probably due to the intermediate depth. A shallow quake would have caused considerable damage and destruction. A slightly larger quake of M 7.8 on April 16, 2016 killed more than 700 people and destroyed hundreds of buildings and cost more than $3 billion in damages. Earthquakes of this size in Ecuador can help promote seismicity in California several months later. This summary will follow this in future issues.

 

In the previous issue of this summary it had been suggested that such an earthquake was possible at this time as:

 

"Conditions favoring seismicity today suggested a strong earthquake near the equator or at high latitudes may occur shortly. A new geomagnetic storm which peaked about 1500 UT when the Caribbean and South America were near local solar noon and tidal stresses which are associated with the full moon also favor seismicity in this longitude zone.

 

The geomagnetic forecast had read:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 11. High latitude geomagnetic field also saw disturbed conditions  with AP at 15.  Kp at high latitudes reach 5 from 1200-1500 UT. This could have helped promote the M 5.5 in Hokkaido at the same time and may have been triggered by it. It is most likely to combine with high tidal stresses helping to promote seismicity in the area of the Caribbean and western South America in the next several days. This could include a large earthquake." (February 20-21, 2019)

 

While the tidal forecast for seismicity had read:

 

"The full moon arrived on February 19, 2019 at 15:53 UT. Longitudes which were in the western hemisphere near 55W and in the east at 125E will experience maximum tidal stresses at this time.  Areas near these longitudes include portions of the Atlantic Ocean in the west and Taiwan, Indonesia and the Philippines, among others in the east. A strong earthquake is likely in the next seven days promoted by tidal stresses. Such earthquakes often occur near local solar noon and midnight. Many other areas could also see tidally promoted seismicity, especially those where fluids (magma and water) are important in local seismicity. This is a super-moon in which the moon makes its closest approach to the earth. This considerably increases the strength of tidal stresses at this time. These include the eastern Caribbean." (February 15-20, February 21-22, 2019 2019)

 

The last earthquake located within about 250 km of today's M 7.5 occurred more than 30 years ago. The only comparable event in the region in this time period was the M 7.8 off Ecuador on April 16, 2016. That event occurred about 350 km northwest of today's epicenter. Forecast 113425 had expected a moderate to strong earthquake about 150 km to the north of today's epicenter was likely around February 21.

 

O: 22FEB2019 10:17:22   2.1S   77.0W Mw=7.5  EMSC   PERU-ECUADOR BORDER REGION   

O: 22FEB2019 10:17:22   2.2S   77.0W mw=7.5  ANSS   ESE of Palora Ecuador

O: 22FEB2019 10:40      2.4S   77.9W mb=5.7  IGP    Zarumilla, Peru.             

O: 22FEB2019 10:17      2.3S   77.3W mb=7.7  IGP    Pastaza, Peru.               

O: 23FEB2019 02:40:00   2.2S   77.4W ML=3.6  EMSC   PERU-ECUADOR BORDER REGION   

P: 21FEB2019 113425     1.0S   78.0W 4.0-5.6 ABAAA  Ecuador                    

 

A pair of moderate earthquakes in  northern Sumatra occurred several hours after the mainshock in Ecuador. These are located near the antipode of that event and may have been promoted by concentrated antipodal energy from Ecuador. The true antipode is at 2N 103E, north and east of the active seismic regions in Sumatra.

But some triggering is likely in Sumatra in coming days.

 

O: 22FEB2019 17:56:40   0.1N  100.2E ML=4.1  EMSC   NORTHERN SUMATRA, INDONESIA  

O: 22FEB2019 15:43:11   0.2N  100.4E ML=4.3  EMSC   NORTHERN SUMATRA, INDONESIA  

P: 15FEB2019 113420     1.0N   99.0E 4.0-5.6 CABAA  So. Sumatera               

 

A swarm of minor earthquakes occurred in the Green River, Wyoming area today.

NEIC reported the earthquake of M 2.9 in Wyoming was felt with intensity II-III in the area(s) of Big Pine, Wyoming. This appears to be a continuation of the activation of the Rocky Mountain area which in recent days has included a series of events in Utah and Montana.  The mainshock of the group was an M 3.0, the largest within about 100 km of this epicenter since an M 3.5 on July 2, 2016. Forecast 113502 had expected regional activity in mid-February. This epicenter (like Southern California) is located at the seventh node (52 degrees) from the Ecuador epicenter and was probably promoted by surface energy from that event.

 

O: 22FEB2019 20:00:28  41.7N  109.7W Ml=2.8  EMSC   WYOMING

O: 22FEB2019 20:08:08  41.7N  109.7W Ml=2.8  EMSC   WYOMING

O: 22FEB2019 19:53:47  41.7N  109.8W Ml=3.0  EMSC   WYOMING

O: 22FEB2019 19:59:07  41.7N  109.7W Ml=2.6  EMSC   WYOMING                      

P: 13FEB2019 113502    39.6N  107.4W 2.0-3.9 CCBAA  Colorado area              

 

GEOMAGNETIC STORM AND FULL MOON MAY BRING STRONG EARTHQUAKES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 21, 2019

 

Conditions favoring seismicity today suggested a strong earthquake near the equator or at high latitudes may occur shortly. A new geomagnetic storm which peaked about 1500 UT when the Caribbean and South America were near local solar noon and tidal stresses which are associated with the full moon also favor seismicity in this longitude zone.

 

The geomagnetic forecast had read:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 11. High latitude geomagnetic field also saw disturbed conditions  with AP at 15. Kp at high latitudes reach 5 from 1200-1500 UT. This could have helped promote the

M 5.5 in Hokkaido at the same time and may have been triggered by it. It is most likely to combine with high tidal stresses helping to promote seismicity in the area of the Caribbean and western South America in the next several days. This could include a large earthquake." (February 20-21, 2019)

 

While the tidal forecast for seismicity had read:

 

"The full moon arrived on February 19, 2019 at 15:53 UT. Longitudes which were in the western hemisphere near 55W and in the east at 125E will experience maximum tidal stresses at this time.  Areas near these longitudes include portions of the Atlantic Ocean in the west and Taiwan, Indonesia and the Philippines, among others in the east. A strong earthquake is likely in the next seven days promoted by tidal stresses. Such earthquakes often occur near local solar noon and midnight. Many other areas could also see tidally promoted seismicity, especially those where fluids (magma and water) are important in local seismicity. This is a super-moon in which the moon makes its closest approach to the earth. This considerably increases the strength of tidal stresses at this time. These include the eastern Caribbean." (February 15-20, 2019)

 

The strongest earthquake in the world today was an M 5.5 in Hokkaido, Japan.  NEIC reported it was felt with intensity VI in Hokkaido at Chitose and V in Kitahiroshima, Ebetsu, Sapporo, and Otaru and II-III in Iwamizawa, Shizunai, Furano, Akabira and Date, Japan. This event occurred at the maximum at high latitudes of today's geomagnetic storm and was probably promoted by it. The last earthquake in Hokkaido within about 200 km of this epicenter with M>=5.5 occurred on September 5, 2018 with M 6.6. This is probably an aftershock of the September event.   Forecast 113552 had expected today's epicenter would be active in this area around February 16.

 

O: 21FEB2019 12:22:41  42.9N  142.0E Mw=5.5  EMSC   HOKKAIDO, JAPAN REGION       

P: 16FEB2019 113552    42.0N  143.0E 3.5-5.6 BAAAA  Hokkaido, Japan            

 

The strongest earthquake in the U.S. or Canada today was an M 4.9 in the Davis Strait east of Canada. This event was not reported felt in this remote area.  The last earthquake of M>=4.9 within about 250 km of this epicenter occurred more than 30 years ago. An M 4.6 hit the region on July 25, 2005.  Forecast 113609 had expected today's event in the Davis Strait was likely around February 21. This was probably promoted by strong tidal stresses  associated with the full moon. The location at 57 West and at high latitudes  is consistent with the strongest tidal stresses at this time (see above and  the TIDAL section of this report).

 

O: 21FEB2019 22:51:39  63.0N   57.2W mb=4.9  EMSC   DAVIS STRAIT                 

P: 21FEB2019 113609    65.0N   52.0W 2.5-3.9 AABAA  Baffin/Davis Strait Canada 

 

An unusually large M 3.8 earthquake shook regions of central and western Montana today.  NEIC reported this earthquake of M 3.8 in Central Montana was felt with intensity V in Three Forks, Montana and IV in Livingston and II-III in the area(s) of Montana at Manhattan, Belgrade, Bozeman, Townsend, Gallatin, Ennis,  This event is also consistent with high tidal stress promotion. It occurred within about 30 minutes of local solar midnight, a time when such tides are maximized. It is the strongest quake within about 100 km of this epicenter since an M 4.4 on June 16, 2017. Forecast 113585 had expected this earthquake was likely around February 18 within about 50 km of this epicenter.

 

O: 22FEB2019 06:44:20  45.9N  111.3W ML=3.8  EMSC   WESTERN MONTANA              

P: 18FEB2019 113585    45.6N  111.9W 2.0-4.0 BAAAA  Yellowstone/Wyoming        

P: 18FEB2019 113585    46.4N  111.4W 2.0-4.1 BAAAA  Yellowstone/Wyoming        

WESTERN TURKEY REMAINS ACTIVE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 20, 2019

 

A moderate earthquake of M 5.0 in western Turkey today continued the activation

of that region. This followed a pair of events of M 4.1 yesterday at an picenter to the northeast of today's.  NEIC reported today's event was felt with intensity IV in Turkey at Ayvalik, Canakkale, Burhaniye, Pamfila, Dikili, Gelibolu, Aliaga, Izmir, Foca, Soma and in Greece at Mitilini and Pamfila.

This is the strongest earthquake within about 200 km of this epicenter since an M 5.1 on October 11, 2019. An M 6.4 occurred about 100 km south of today's epicenter on June 12, 2017. It was preceded by a series within  about 50 km of today's epicenter on February 6-7, 2017 (M 5.2-5.3). Forecast 113488 had expected today's activity was likely in this area in mid-February, A series of events yesterday was covered in this summary as:

 

 

"A series of earthquakes also occurred today near Istanbul in Western Turkey with the largest of M 4.1 and 4.1. These events may indicate that the Anatolian Fault in this area is nearing a moderate rupture. A major earthquake (which is expected in the near-term) in this area could be a major disaster and many geophysicists are watching for precursory activity to such an event.  When a foreshock to the east occurred on December 20, 2018 this summary noted:

 

"A strong earthquake is expected in this area. Moderate foreshocks such as this are likely to continue in the region in preparation for this upcoming event. The last earthquake in the region within about 150 km of Istanbul, Turkey with M>=4.4 occurred on November 16, 2015 with M 4.4. The last of larger magnitude was an 5.1 on June 7, 2012." (December 20, 2018, February 19-20, 2019) 

 

This event is at 102 degrees from the M 6.8 under Brazil of January 5, 2019 and may have been promoted from that source.

 

O: 20FEB2019 19:42:07  39.6N   26.5E mb=4.0  EMSC   NEAR THE COAST OF WESTERN TURK

O: 20FEB2019 18:23:28  39.6N   26.5E mb=5.1  EMSC   NEAR THE COAST OF WESTERN TURKE

P: 12FEB2019 113488    39.0N   27.0E 3.0-4.5 CAAAA  Aegean Sea                 

 

An unusual earthquake of M 4.6 also occurred south this in the region of Libya. It was felt lightly in the epicentral area. The last (and only) earthquake of M>=4.6 within about 200 km of this epicenter in Libya occurred February 9, 2012 with M 4.8. Forecast 113229 had expected activity northeast of this was likely in early February.

 

O: 21FEB2019 02:19:35  32.8N   21.7E mb=4.6  EMSC   NEAR COAST OF LIBYA          

P:  9FEB2019 113229    34.0N   24.0E 3.0-4.6 DBCAA  Crete                      

 

An unusual earthquake of M 4.6 was widely felt in Thailand today. NEIC reported maximum intensity VI in Thailand at Phayao and II-III in Chiang Mai at Bansai, Maerim, Chiang Mai, Chiang Rai, Hongdong, Sanpatong, Lampand and Bangkok. The last earthquake of M>=4.6 in Thailand within about 150 km of this epicenter occurred as an M 6.0 on May 5, 2014. This may be an aftershock of that event.  Forecast 113444 had expected activity to the west of this in mid-February.

 

O: 20FEB2019 09:05:42  19.2N   99.6E mb=4.6  EMSC   THAILAND                     

O: 20FEB2019 10:59:03  19.3N   99.6E ML=3.7  EMSC   THAILAND                     

P: 13FEB2019 113444    19.0N   96.0E 4.0-5.4 CACAA  Andaman Islands             

 

Seismicity in Utah today shifted back to the north as aftershocks south of Salt Lake City. Events of M 2.1 and 2.6 among others were located in the aftershock zone today. The mainshock occurred February 15, 2019 with M 3.7.  NEIC reported today's earthquake of M 2.5 in Central Utah was felt with intensity II-III in the area(s) of Riverton, Draper, Lehi, Herriman, South Jordan, American Fork, Saratoga Springs, Bandy, Eagle Mountain, Utah.  Forecast 113544 had expected this activity was likely around February 21 within this area.

 

O: 21FEB2019 02:37:41  40.5N  111.9W ML=2.1  EMSC   WASATCH FRONT URBAN AREA, UTAH

O: 21FEB2019 03:08:38  40.5N  112.0W Ml=2.5  EMSC   WASATCH FRONT URBAN AREA, UTAH

P: 21FEB2019 113544    39.5N  111.9W 2.0-3.9 AAAAA  Utah area                  

 

The strongest earthquake in the world today was an M 5.6 in the Fiji Islands. It was not reported felt in this area. This event was probably promoted by Tropical Cyclone Oma which is current in thie area as suggested in earlier episodes of this summary:

 

"track to the southwest over the next several days. Seismic enhancement in the region of Vanuatu could accompany the passage of this storm through the area. A moderate to large earthquake in the Loyalty Islands is possible as Oma passes over that region  around February 18-20." (February 18-20, 2019)

 

Forecast 113657 expected this activity within about 100 km was likely around February 19.

 

O: 21FEB2019 06:34:38  21.0S  178.8W Mw=5.6  EMSC   FIJI REGION                  

P: 19FEB2019 113657    22.0S  180.0W 4.0-5.7 AAAAA  Tonga Islands              

 

UNUSUAL QUAKES IN UTAH; ANATOLIAN ZONE ACTIVE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 19, 2019

 

While the largest earthquake of the day was an M 5.6-5.9 in the Molucca Sea, more interesting events occurred in western Turkey and in Central Utah, continuing recent activation of those areas over the past week.

 

A pair of earthquakes of M 4.1 and 4.0 occurred in Central Utah today. NEIC reported these events were felt with intensity IV in Joseph, Utah and II-III in Monroe and Richfield. They appear to have been promoted by the full moon as they began within about 15 minutes of local solar midnight. Earth tides maximize at this hour especially at full and new moons. This summary had expected tidal triggering at this time as:

 

"The full moon will arrive on February 19, 2019 at 15:53 UT. Longitudes which are in the western hemisphere near 55W and in the east at 125E will experience maximum tidal stresses at this time.  portions of the Atlantic Ocean in the west and Taiwan, Indonesia and the Philippines, among others in the east. A strong earthquake is likely in the next seven days promoted by tidal stresses. Such earthquakes often occur near local solar noon and midnight. Many other areas could also see tidally promoted seismicity, especially those where fluids (magma and water) are important in local seismicity. This is a super-moon in which the moon makes its closest approach to the earth. This considerably increases the strength of tidal stresses at this time. These include the eastern Caribbean." (February 15-29, 2019)

 

The last earthquake in Utah within about 200 km of today's epicenter with M>=4.1 occurred on January 15, 2016 with M 4.3 about 200 km southwest of today's epicenter. The last within about 100 km was an M 4.6-4.7 more than eight years ago on January 3, 2011. A foreshock near this epicenter of M 3.8 occurred September 12, 2018 with M 3.8. Activity leading up to today's earthquakes has been occurring over the past week. This included an M 3.3 on February 16, 2019. At the time this summary noted this event as:

 

 

"The strongest earthquakes in the U.S. outside of Alaska today continued in  the region from Utah north to Wyoming. The largest of these was an M 3.3 in Utah, but an M 3.1 also occurred in Yellowstone. These continued activation of the

region which included an M 3.7-3.8 yesterday as noted in the previous issue of this summary. The M 3.3 in Utah was not an aftershock of the M 3.7 south of Salt Lake City, Utah (where an M 2.5 aftershock occurred today) but occurred about 150 km south of that epicenter." (February 17, 2019)

 

Forecast 113544 had expected this area of Utah to be active in mid-February.

 

O: 20FEB2019 07:05:37  38.9N  112.9W ml=4.0  ANSS   WSW of Fillmore Utah

O: 20FEB2019 07:05:16  38.7N  112.5W ml=4.1  ANSS   SSW of Fillmore Utah

O: 20FEB2019 07:05:37  38.9N  112.9W Ml=4.0  EMSC   UTAH                         

P: 12FEB2019 113544    38.7N  112.5W 2.0-3.9 CAAAA  Utah area                  

P: 21FEB2019 113544    39.5N  111.9W 2.0-3.9 AAAAA  Utah area                  

 

A series of earthquakes also occurred today near Istanbul in Western Turkey with the largest of M 4.1 and 4.1. These events may indicate that the Anatolian Fault in this area is nearing a moderate rupture. A major earthquake (which is expected in the near-term) in this area could be a major disaster and many geophysicists are watching for precursory activity to such an event.  When a foreshock to the east occurred on December 20, 2018 this summary noted:

 

"A strong earthquake is expected in this area. Moderate foreshocks such as this are likely to continue in the region in preparation for this upcoming event. The last earthquake in the  region within about 150 km of Istanbul, Turkey with M>=4.4 occurred on November 16, 2015 with M 4.4. The last of larger magnitude was an 5.1 on June 7, 2012." (December 20, 2018)

 

Forecast 113575 had expected today's event within this area of western Turkey was likely around February 15. This activity is at 102 degrees from the M 6.8 of January 5, 2019 under Brazil and may have been promoted from that source..

 

O: 20FEB2019 01:27:41  40.4N   27.2E ML=3.3  EMSC   WESTERN TURKEY               

O: 20FEB2019 00:27:57  40.4N   27.2E ML=3.6  EMSC   WESTERN TURKEY               

O: 19FEB2019 19:48:42  40.4N   27.2E ML=4.1  EMSC   WESTERN TURKEY                

O: 19FEB2019 21:33:55  40.4N   27.2E mb=4.1  EMSC   WESTERN TURKEY               

P: 15FEB2019 113575    41.0N   29.0E 3.0-5.3 BABAA  Romania/NW Turkey          

 

The strongest earthquake of the day was an M 5.6-5.9 in the region of the Molucca Sea, Indonesia. BMG reported this earthquake at M 5.9 was felt with intensity II-III in Ternate and II in Manado, Bitung and Kotamobagu, Molucca, Indonesia. This continues the activation of this region which most recently has included events to the north of this on February 7 (M 5.7) and an M 6.6 on January 6, 2019. Today's event may be a regional aftershock of the January quake.  Forecast 113417 had expected this activity was likely about 100 km to the north of today's epicenter around February 16.

 

O: 20FEB2019 00:10:40   0.7N  126.2E Mw=5.6  EMSC   MOLUCCA SEA                  

O: 20FEB2019 00:10:39   0.7N  126.2E mw=5.6  ANSS   Kota Ternate Indonesia

O: 20FEB2019 00:10:41  00.8N  126.2E MS=5.9  BMG  Felt with intensity II-III

P: 16FEB2019 113417     2.0N  126.0E 4.0-5.5 BBAAA  Mindanao, Philippines      

 

The strongest earthquake in the U.S. or Canada today was an M 4.3 in Southern Alaska.  NEIC reported this earthquake of M 3.9 in Southern Alaska was felt with intensity II-III in the area(s) of Homer, Alaska.  The last earthquake of M>=4.3 within about 100 km of this epicenter was an M January 3, 2019 (M 4.4) and an M 4.9 on January 2, 2019. Forecast 113611 had expected today's event was likely around February 17.

 

O: 20FEB2019 06:16:40  59.3N  153.7W ML=4.3  EMSC   SOUTHERN ALASKA              

P: 17FEB2019 113611    60.0N  153.5W 3.2-4.9 BAAAA  Central Alaska             

 

A pair of moderate earthquakes in the Loyalty Islands and Vanuatu of M 4.6 and M 4.7 may have been promoted by Tropical Cyclone Oma. This summary had  noted this possibility in previous issues as:

 

"Seismic enhancement in the region of Vanuatu could accompany the passage of this storm through the area. A moderate to large earthquake in the Loyalty Islands is possible as Oma passes over that region around February 18-20." (February 14-19, 2019)

 

Forecasts 113644 and 113645 had expected this activity within about 100 km

of these epicenters in mid-February.

 

O: 19FEB2019 08:10:28  13.6S  167.2E mb=4.6  EMSC   VANUATU                       

P: 19FEB2019 113644    13.0S  166.0E 4.0-5.4 AAAAA  Vanuatu Islands            

 

O: 19FEB2019 13:33:39  20.9S  168.7E mb=4.7  EMSC   LOYALTY ISLANDS              

P: 15FEB2019 113660    20.0S  169.0E 4.0-5.4 BAAAA  Vanuatu Islands            

P: 19FEB2019 113645    19.0S  168.0E 4.0-5.4 ABAAA  Vanuatu Islands            

 

ANTIPODAL AREAS OF VIRGIN ISLANDS; JAVA ACTIVE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 18, 2019

 

Antipodal areas of the Virgin Islands/Puerto Rico(M 4.8-4.9)  and Java Indonesia (M 5.6-5.9) saw unusual, felt earthquakes today. These were joined by an unusually large aftershock of M 4.6 in the Anchorage, Alaska zone. This activity was expected to be associated with the new moon which is complete today.  The moderate earthquake occurred with M 4.9 in the Virgin Islands, Caribbean today. NEIC reported it was felt with intensity IV in Bayamon, Puerto Rico and II-III in Road Town, Tortola, British Virgin Islands; Saint Thomas and Saint John, American Virgin Islands and in Puerto Rico at Fajardo, Luquillo, San Juan, Trujillo, Toa Baja, and Bayamon, Puerto Rico. This event was probably triggered by high tidal stresses associated with the super-moon which arrives today. This summary had noted this antipodal possibility in previous issues as:

 

 

"The full moon will arrive on February 19, 2019 at 15:53 UT. Longitudes which are in the western hemisphere near 55W and in the east at 125E will experience maximum tidal stresses at this time.  portions of the Atlantic Ocean in the w st and Taiwan, Indonesia and the Philippines, among others in the east. A strong earthquake is likely in the next seven days promoted by tidal stresses. Such earthquakes often occur near local solar noon and midnight. Many other areas could also see tidally promoted seismicity, especially those where fluids (magma and water) are important in local seismicity. This is a super-moon in which the moon makes its closest approach to the earth. This considerably increases the strength of tidal stresses at this time. These include the eastern Caribbean." (February 15-18. 2019)

 

and

 

"An earthquake of M 3.5 shook areas of Puerto Rico today. This is an area which could be affected by strong tides with the full moon on February 19. More such regional seismicity is likely at that time." (February 16-17, 2019)

 

While an M 4.9 occurred within about 200 km of today's epicenter on November 14, 2018, the last such event with greater magnitude in the Virgin Islands was an M 5.0 on January 10, 2013 more than six years ago. Forecasts 113454 and 113466 had expected today's event was likely within about 50 km around February 19.

 

O: 19FEB2019 00:23:57  19.1N   64.4W Md=3.3  EMSC   VIRGIN ISLANDS REGION        

O: 19FEB2019 00:01:43  19.3N   64.6W Md=3.4  EMSC   VIRGIN ISLANDS REGION        

O: 18FEB2019 23:45:08  19.4N   64.7W Md=3.4  EMSC   VIRGIN ISLANDS REGION        

O: 19FEB2019 01:01:15  19.4N   64.8W Md=3.0  EMSC   VIRGIN ISLANDS REGION        

O: 19FEB2019 01:35:07  19.4N   64.8W Md=3.3  EMSC   VIRGIN ISLANDS REGION        

O: 18FEB2019 23:38:05  19.4N   64.9W Mw=4.9  EMSC   VIRGIN ISLANDS REGION        

O: 19FEB2019 01:15:26  19.5N   65.0W Md=3.3  EMSC   VIRGIN ISLANDS REGION        

O: 18FEB2019 23:56:56  19.7N   65.1W Md=3.2  EMSC   VIRGIN ISLANDS REGION        

P: 19FEB2019 113454    19.0N   64.0W 3.0-5.1 AAAAA  Leeward Islands            

P: 19FEB2019 113466    19.0N   66.0W 3.4-5.1 AAAAA  Puerto Rico                

 

The strongest earthquake in the world today occurred in the region south of Java, Indonesia with M 5.6 (EMSC) to M 5.9 (BMG). NEIC reported it was felt lightly with intensity II in Java at Malang, Kedungwani, Ponorogo and in Kuta and Denpasar, Bali, Indonesia. BMG reported it was felt with intensity III-IV in Lumajang, III in Malang, Karangkates, Blitar, Sawahan and II-III in Kuta and Nusa Dua, Java, Indonesia. It was followed by a series of moderate aftershocks. The mainshock occurred near local solar midnight and was probably promoted by tidal stresses associated with the full moon. The last earthquake with M>=5.6 within about 250 km of this epicenter occurred as an M 5.7 on November 16, 2016 (M 5.7). The last in this area of M>=5.9 was an M 6.0 on July 26, 2015. Forecast 113436 had expected this event within about 50 km of today's epicenter was likely around February 16. This epicenter is located at 102 degrees from the M 7.1 in Anchorage, Alaska of November 30, 2018 and at 104 degrees from the event in the South Sandwich Islands of December 11, 2018 (M 7.1). This is a distance at which seismic energy is concentrated on the earth's surface following strong earthquakes and triggering is likely.

  

O: 18FEB2019 22:59:54   8.9S  113.1E ML=4.2  EMSC   JAVA, INDONESIA              

O: 19FEB2019 06:08:43   9.4S  112.9E ML=4.1  EMSC   SOUTH OF JAVA, INDONESIA     

O: 18FEB2019 19:30:27   9.4S  112.9E Mw=5.6  EMSC   SOUTH OF JAVA, INDONESIA     

O: 18FEB2019 19:30:22   9.5S  112.9E mw=5.6  ANSS   Krajan Tambakrejo Indonesia

O: 18FEB2019 19:30:23  09.7S  112.7E MS=5.9  BMG  Felt with intensity III-IV

O: 18FEB2019 23:52:56   9.5S  112.8E ML=4.5  EMSC   SOUTH OF JAVA, INDONESIA     

O: 18FEB2019 22:03:00   9.6S  112.8E ML=3.9  EMSC   SOUTH OF JAVA, INDONESIA     

O: 18FEB2019 20:18:45   9.7S  112.8E ML=3.7  EMSC   SOUTH OF JAVA, INDONESIA     

O: 18FEB2019 21:45:28   9.7S  112.8E ML=3.7  EMSC   SOUTH OF JAVA, INDONESIA     

O: 18FEB2019 22:21:38   9.7S  112.8E ML=4.3  EMSC   SOUTH OF JAVA, INDONESIA     

P: 16FEB2019 113436     9.0S  113.0E 4.0-5.4 AAAAA  So. of Bali                

 

The strongest earthquake in the U.S. or Canada today was a moderate M 4.4 in the Anchorage, Alaska aftershock zone. NEIC reported it was felt with maximum intensity IV in Anchorage and Elmendorf, AFB, Alaska and II-III in Fort Richardson, Willow, Wasilla, Alaska. This earthquake is the strongest aftershock in the Anchorage, Alaska zone where an M 7.1 on November 30, 2018 has been followed by numerous smaller aftershocks in the past two months. The last event of M>=4.6 in the area occurred more than a month ago on January 13, 2019 with M 5.0. Only four aftershocks of M>=4.6 have occurred since the immediate aftershocks of early December, 2018. Forecast 113613 had expected this event was likely around February 17.

 

O: 18FEB2019 17:02:45  61.4N  149.9W mb=4.6  EMSC   SOUTHERN ALASKA              

O: 19FEB2019 06:59:07  61.9N  149.3W ml=3.5  EMSC   SOUTHERN ALASKA               

P: 17FEB2019 113613    61.3N  150.9W 3.2-4.9 AAAAA  Central Alaska             

 

STRONG EARTHQUAKE ON GEOMAGNETTIC EQUATOR IN NEW IRELAND

 

EARTHQUAKE SUMMARY FOR FEBRUARY 17, 2019

 

The strongest earthquake in the world today occurred at a deep focus north of New Ireland with M 6.5. This event occurred within about 5 degrees of the geomagnetic equator. To the north a new tropical cyclone is forming. The combination of these two stressors may have been sufficient to push this epicenter to rupture at this time. This is the strongest earthquake in the world in nearly three weeks following an M 6.6 in Chiapas, Mexico on February 1, 2019. This event occurred within about 30 minutes of local solar midnight, a time when maximum earth tides occur and was probably triggered by tidal forces. The tidal forecast for the full moon had read:

 

"The full moon will arrive on February 19, 2019 at 15:53 UT. Longitudes which are in the western hemisphere near 55W and in the east at 125E will experience maximum tidal stresses at this time.  portions of the Atlantic Ocean in the west and Taiwan, Indonesia and the Philippines, among others in the east. A strong earthquake is likely in the next seven days promoted by tidal stresses. Such earthquakes often occur near local solar noon and midnight. Many other areas could also see tidally promoted seismicity, especially those where fluids (magma and water) are important in local seismicity. This is a super-moon in which the moon makes its closest approach to the earth. This considerably increases the strength of tidal stresses at this time." (February 15-17, 2019).

 

While events associated with the geomagnetic storm  were expected as:

 

"This appears to conclude a new geomagnetic storm that began on February 13. Seismicity along the geomagnetic equator may be slightly enhanced but is more likely to be promoted at high latitudes through February 17." (February 12-16, 2019)

 

This is the strongest earthquake within about 150 km of today's epicenter since an M 6.7 on August 31, 2016. More recently a series of earthquakes about 250 km southwest of today's epicenter occurred in March, 2018 (M 6.8, 6.9, 6.6). Those were probably aftershocks of an M 7.9 of December 17, 2016.

 

O: 17FEB2019 14:35:56   3.4S  152.1E Mw=6.5  EMSC   NEW IRELAND REGION, P.N.G.   

P: 18FEB2019 113429     4.0S  152.0E 4.0-5.6 AAAAA  New Britain                 

 

The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Rat Islands, Aleutians, Alaska. It was not reported felt in the area. This is the strongest earthquake in the eastern Rat Islands within about 100 km of this epicenter since an M 4.8 on March 19, 2018. The last such event in the Rat Islands of larger magnitude was an M 5.1 nearly a year ago on March 2, 2018. Forecast 113603 had expected today's event was likely around February 15.

 

O: 18FEB2019 03:41:46  51.3N  179.4E mb=4.8  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 15FEB2019 113603    52.0N  177.0E 4.0-5.8 BABAA  Rat Islands                

 

Two unusually large earthquake occurred in California today - an M 3.8 north of San Francisco and an M 3.4 in the Tehachapi area of central California north of

Los Angeles. The event north of San Francisco was widely felt in the epicentral area. This is the strongest earthquake in this area north of San Francisco since an M 4.1 on May 22, 2015. An M 4.4 occurred about 50 km south of this in San Francisco on January 4, 2018 after a similar event of M 4.0 on August 17, 2015. Forecasts 113498 and 113499 had expected this region to see a possibly moderate sized event around February 16-17. Today's event occurred near local solar midnight and may have been encouraged by tidal forces which maximize at this time.

 

NEIC reported this earthquake of M 3.7-3.8 north of San Francisco, California was felt with intensity IV in Yountville, Napa, and II-III in the area(s) of Glen Ellen, Sonoma, Kenwood, Saint Helena, Petaluma and Santa Rosa, California.

 

O: 17FEB2019 09:55:24  38.4N  122.4W ML=3.8  EMSC   NORTHERN CALIFORNIA          

P: 17FEB2019 113498    37.7N  121.9W 2.5-4.6 AAAAA  Central California         

P: 16FEB2019 113499    38.7N  122.7W 2.5-4.6 AAAAA  Central California         

 

The earthquake in central California of M 3.4 which occurred near Tehachapi, California was also widely felt. NEIC reported this earthquake of M 3.4 in Central California was felt with intensity IV in Keene, California and II-III in the area(s) of California at Caliente, Tehachapi, Lake Isabella, and Mojave.  This is the strongest earthquake within about 50 km of today's epicenter since  an M 3.8 on April 16, 2018. The only other such event in the area in the past 1.5 years was an M 3.7 on April 13, 2018.  Forecast 113532 expected today's event within about 25 km of the epicenter was likely around February 16.

 

O: 17FEB2019 11:36:47  35.3N  118.5W ML=3.4  EMSC   CENTRAL CALIFORNIA           

P: 16FEB2019 113532    35.6N  118.4W 2.5-4.4 AAAAA  So. California             

 

MINOR SWARM IN RYUKYU ISLANDS, JAPAN

 

EARTHQUAKE SUMMARY FOR FEBRUARY 16, 2019

 

Global seismicity was at quiet levels today as the effects of the geomagnetic storm diminished and with the full moon still two days away. There were no major ocean storms to move plates at this time either. The exception of Tropical Cyclone Oma which is slowly moving west of the Vanuatu Islands, and which is capable of promoting seismicity in that region. The strongest earthquakes in the world today were an M 5.0 and 5.2 in the region of the Ryukyu Islands, Japan north of Taiwan. These events were felt lightly in the region of Okinawa, Japan but did no damage. The last earthquake within about 150 km of these epicenters with M>=5.1 was an M 5.2 nearly a year ago on March 1, 2018. The last of larger magnitude was an M 6.0 on May 9, 2017.  Forecast 113485 had expected today's events were likely to the southwest around February 20.

 

O: 17FEB2019 02:13:43  25.2N  124.6E mb=5.0  EMSC   NORTHEAST OF TAIWAN          

O: 16FEB2019 09:06:36  25.2N  125.1E mb=4.8  EMSC   SOUTHWESTERN RYUKYU ISL., JAPA

O: 16FEB2019 10:01:29  25.4N  125.0E Mw=5.1  EMSC   NORTHEAST OF TAIWAN          

O: 16FEB2019 10:01:28  25.3N  125.0E Mw=5.2  ANSS   NORTHEAST OF TAIWAN          

P: 20FEB2019 113485    24.0N  123.0E 4.0-5.4 BBBAA  Taiwan                     

 

An M 4.9 earthquake in the southwest Indian Ridge today was not felt in that remote region. It is located near the antipode of Baja, California (at 31N 120W) and could promote seismicity in that area in the next several days. The event in the Indian Ocean was the strongest within about 150 km of that epicenter since an M 4.9 on November 3, 2018 and prior to that an M 5.8 on October 21, 2018.  

Forecast 113655 had expected a moderate quake in this area was possible around February 19. This event is at 144 degrees from the Anchorage Alaska swarm and may have been promoted from that source.

 

O: 16FEB2019 22:28:36  30.7S   59.4E mb=4.9  EMSC   SOUTHWEST INDIAN RIDGE       

P: 19FEB2019 113655    29.0S   62.0E 4.0-5.6 BBBAA  So. Indian Ocean           

 

The strongest seismicity in the U.S. or Canada today continued in the Aleutians of Alaska where an M 5.0 and M 5.1 occurred yesterday. The strongest event today was an M 3.9 in the Central Aleutians. It was an aftershock of the M 5.0 which hit there yesterday. It was not reported felt in this remote area. Forecast 113588 had expected this event within about 100 km was likely in mid-February.

 

O: 16FEB2019 10:49:09  51.3N  176.7W mb=3.9  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 12FEB2019 113588    51.7N  175.3W 3.5-5.1 BAAAA  Andreanoff Isls, Aleutians 

 

The strongest earthquakes in the U.S. outside of Alaska today continued in  the region from Utah north to Wyoming. The largest of these was an M 3.3 in Utah, but an M 3.1 also occurred in Yellowstone. These continued activation of the region which included an M 3.7-3.8 yesterday as noted in the previous issue of this summary. The M 3.3 in Utah was not an aftershock of the M 3.7 south of Salt Lake City, Utah (where an M 2.5 aftershock occurred today) but occurred about 150 km south of that epicenter. It is the largest earthquake within about 100 km of this epicenter since an M 3.6 on October 30, 2018 and prior to that a surface event of M 3.8 on September 12, 2018. Forecast 113544 had expected today's event within about 10 km of the epicenter was likely in mid-February.

 

NEIC reported this earthquake of M 3.3 in Utah was felt with intensity II-III in the area(s) of Utah at Fillmore, Delta, Parson, Lehi, Riverton, Draper, South Jordan and Salt Lake City.

 

O: 16FEB2019 22:05:31  38.7N  112.5W ML=3.3  EMSC   UTAH                         

P: 12FEB2019 113544    38.7N  112.5W 2.0-3.9 BAAAA  Utah area                  

 

O: 17FEB2019 02:00:53  40.5N  111.9W ML=2.5  EMSC   WASATCH FRONT URBAN AREA, UTAH

P: 18FEB2019 113544    39.7N  111.9W 2.0-3.9 AAAAA  Utah area                  

 

The M 3.1 in Yellowstone, Wyoming is the first of M 3.1 or greater in the area in nearly two months, since an M 3.1 on December 20, 2018. The last of larger magnitude in the area occurred on September 17, 2017 with M 3.1-3.2. Forecast 113584 had expected this event was likely in mid-February within about 25 km of today's epicenter.

 

NEIC reported this earthquake of M 3.1 in Yellowstone, Wyoming was felt with intensity II-III in the area(s) of Yellowstone National Park, Wyoming.

 

O: 16FEB2019 21:22:50  44.5N  111.0W ML=3.1  EMSC   YELLOWSTONE NAT. PARK, WYOMING

P: 12FEB2019 113584    44.6N  110.8W 2.0-4.1 BAAAA  Yellowstone/Wyoming        

 

An earthquake of M 3.5 shook areas of Puerto Rico today. This is an area which could be affected by strong tides with the full moon on February 19. More such regional seismicity is likely at that time. The last event with M>=3.5 within about 50 km  of today's epicenter was an M 4.4 on December 9, 2018 and prior to that an M 3.9 on May 10, 2018, the only such events in the area in the past 1.5 years. Forecast 113466 had expected this activity in Puerto Rico was likely around February 13. Puerto Rico is located that the fifth node (72 degrees) from Anchorage, Alaska and could be influenced by energy from that source.

 

NEIC reported this earthquake of M 3.8 in Puerto Rico was felt with intensity II-III in the area(s) of Puerto Rico at Lares, Mayaguez, San German.

 

O: 16FEB2019 08:55:01  18.3N   67.0W ML=3.5  EMSC   PUERTO RICO                  

O: 16FEB2019 08:55:02  18.2N   67.0W ML=3.8  ANSS   PUERTO RICO                  

P: 13FEB2019 113466    19.0N   67.0W 3.4-5.1 BAAAA  Puerto Rico                

 

ENHANCED SEISMICITY AT HIGH LATITUDES CONTINUES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 15, 2019

 

The enhancement of seismicity at high latitudes following the geomagnetic storm of February 13-14 continued today. Unusual moderate earthquakes occurred in the Aleutians in the central Andreanof Islands with M 5.1; in the eastern Aleutians with M 5.0; Vancouver Island, B.C. Canada (M 4.1, 4.0); in the Azores region of the North Atlantic (M 5.3) and in northern Utah (M 3.8) among others. In previous issues of this summary this seismic enhancement at high latitudes had been expected to follow the current geomagnetic storm as:

 

"This continues a new geomagnetic storm that began on February 13. Seismicity along the geomagnetic equator may be slightly enhanced but is more likely to be promoted at high latitudes through February 17." (February 14-15, 2019)

 

An M 3.7-3.8 shook areas of Utah today south of the Great Salt Lake. NEIC reported it was felt with intensity IV in Utah at Riverton, Draper, Lehi, Harriman, and Eagle Mountain with intensity II-III in South Jordan, American Fork, Saratoga, Sandy Utah. A slightly smaller foreshock of M 3.2 was felt in the same general area with intensity II-III and in Riverton, Utah with IV.

These events followed an M 2.5 which occurred in Arizona to the south. That event was reported with intensity II-III in Morristown and Glendale, Arizona. The mainshock in Utah was the strongest within about 150 km of this epicenter since an M 3.7 on December 29, 2014. Forecasts 113544 had expected this activity within this area was likely in mid-February.

 

O: 15FEB2019 12:02:50  40.5N  111.9W ML=3.3  EMSC   WASATCH FRONT URBAN AREA, UTAH

O: 15FEB2019 12:09:51  40.5N  111.9W ml=3.7  ANSS   S of Bluffdale Utah

O: 15FEB2019 12:09:51  40.5N  111.9W ML=3.8  EMSC   WASATCH FRONT URBAN AREA, UTAH

O: 15FEB2019 12:11:57  40.5N  111.9W Md=2.2  EMSC   WASATCH FRONT URBAN AREA, UTAH

O: 15FEB2019 16:05:43  40.5N  111.9W Ml=2.2  EMSC   WASATCH FRONT URBAN AREA, UTAH

P: 18FEB2019 113544    39.7N  111.9W 2.0-3.9 AAAAA  Utah area                  

P: 21FEB2019 113544    39.5N  111.9W 2.0-3.9 CAAAA  Utah area                  

 

O: 15FEB2019 08:22:03  36.5N  112.8W ML=2.5  EMSC   ARIZONA                      

O: 15FEB2019 08:22:03  36.5N  112.8W ml=2.5  ANSS   SSW of Fredonia Arizona

P: 14FEB2019 113543    37.0N  113.8W 2.0-4.1 AAAAA  Utah area                  

 

The strongest earthquakes in the U.S. or Canada today were an M 5.1 in the Unimak area, Aleutians and an M 5.0 in the central Andreanof Islands, Aleutians, Alaska. NEIC reported it was felt with intensity III in Adak, Alaska. The eastern event south of Alaska of M 5.1 was not reported in the epicentral area near Unimak Island and False Pass, Alaska. The last earthquake within about 150 km of this epicenter with M>=5.1 was an M 5,2 on October 1, 2016. A strong M 6.0. it about 150 km northeast of this on December 31, 2019. This may be a regional aftershock of that quake. Forecast 113607 had expected today's quake was likely within about 100 km of this epicenter around February 15.

 

O: 15FEB2019 22:54:17  53.8N  162.9W Mw=5.1  EMSC   SOUTH OF ALASKA              

O: 15FEB2019 22:54:17  53.7N  162.9W mw=5.1  ANSS   False Pass Alaska

P: 15FEB2019 113607    54.5N  163.5W 3.5-5.1 AAAAA  Unimak Islands, Aleutians  

 

The event of M 5.0 in the Andreanof Islands was the strongest within about 150 km of that epicenter since an M 5.1 on January 6, 2019, an aftershock of an M 5.9 on January 5. Those events occurred about 100 km west of today's epicenter. The last such event within about 100 km of today's quake was an M 6.3 on August 23, 2018. Today's event was reported with intensity III in Adak, Alaska. Forecasts 113588 and 113590 had expected a moderate event in this area in mid February.

 

O: 15FEB2019 18:11:45  51.6N  176.8W mb=5.0  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 12FEB2019 113588    51.7N  175.3W 3.5-5.1 BAAAA  Andreanoff Isls, Aleutians 

P: 15FEB2019 113590    52.2N  178.9W 3.5-4.9 AABAA  Andreanoff Isls, Aleutians 

 

The swarm in the Vancouver Island area of British Columbia which began two days ago with an M 5.2 continued today. Earthquakes today included those of M 4.0, 4.1, 3.8, 3.9 among others. Forecast 113591 had expected this activity was likely within about 10 km of these epicenters around February 13.

 

O: 15FEB2019 06:27:37  50.7N  130.1W mb=4.0  EMSC   VANCOUVER ISLAND, CANADA REGIO

O: 15FEB2019 06:58:21  50.5N  130.2W ML=3.4  NRCA  194 km W   of Pt. Hardy

O: 15FEB2019 06:27:36  50.6N  130.3W ML=4.1  NRCA  201 km W   of Pt. Hardy

O: 15FEB2019 06:05:17  50.5N  130.3W ML=3.9  NRCA  206 km W   of Pt. Hardy

O: 15FEB2019 00:08:32  50.5N  130.4W ML=3.8  NRCA  209 km W   of Pt. Hardy

O: 14FEB2019 12:29:20  50.5N  130.4W ML=3.5  NRCA  209 km W   of Pt. Hardy

P: 13FEB2019 113591    50.6N  130.5W 3.0-5.0 AAAAA  British Colombia           

 

The largest earthquake of the day occurred in the Azores with M 5.3. This follows an event to the southwest of M 6.2 which occurred yesterday as reported in the previous issue of this summary. Today's event was felt lightly in  the Azores. It was preceded by an M 4.7 about an hour earlier. These may be regional aftershocks of the M 6.1 yesterday which this summary had noted:

 

"A strong earthquake of M 6.2, followed by an M 5.0 aftershock occurred in the Northern Mid-Atlantic Ridge today. These events were not felt in this remote area and no tsunami was generated  or expected. This is located at an unusual epicenter south of the Azores." (February 14-15, 2019)

 

Today's event is the strongest in the Azores region within about 200 km of the epicenter since an M 5.5 on August 30, 2017. An M 5.2-5.3 hit near this on  April 14, 2018. Forecast 113297 had expected a moderate to moderately large

 event in this area was likely in early to mid=February.

 

O: 16FEB2019 06:45:54  41.2N   29.4W Mw=5.3  EMSC   AZORES ISLANDS REGION        

O: 16FEB2019 05:56:12  41.2N   29.4W mb=4.7  EMSC   AZORES ISLANDS REGION        

P:  5FEB2019 113297    40.0N   29.0W 4.0-5.6 CAAAA  No. Mid-Atlantic Ridge     

 

STRONG QUAKE IN NORTHERN MID-ATALNTIC RIDGE

 

EARTHQUAKE SUMMARY FOR FEBRUARY 14, 2019

 

A strong earthquake of M 6.2, followed by an M 5.0 aftershock occurred in the Northern Mid-Atlantic Ridge today. These events were not felt in this remote area and no tsunami was generated or expected. This is located at an unusual epicenter south of the Azores. The last earthquake within about 250 km of this epicenter in the Northern  Mid-Atlantic Ridge occurred as an M 6.3 on May 24, 2010. Other events in the region in the past 30 years with equal or greater magnitude occurred in August, 1990 (M 6.3); April, 1995 (M 6.2); April, 2003 (M 6.1).  Forecast 113516 had expected a possibly moderately large event in this region of the Atlantic was possible around February 13.

 

O: 14FEB2019 20:43:31  35.3N   36.1W mb=5.0  EMSC   NORTHERN MID-ATLANTIC RIDGE  

O: 14FEB2019 20:43:32  35.4N   35.9W mb=5.0  ANSS   Northern Mid-Atlantic Ridge"

O: 14FEB2019 19:57:05  35.4N   36.1W mw=6.2  ANSS   Northern Mid-Atlantic Ridge"

O: 14FEB2019 19:57:06  35.4N   36.3W Mw=6.1  EMSC   NORTHERN MID-ATLANTIC RIDGE  

P: 13FEB2019 113516    38.0N   32.0W 4.0-5.7 ACCAA  No. Mid-Atlantic Ridge     

 

An earthquake of M 5,4 on the geomagnetic equator today was strongly felt in central Peru. NEIC reported maximum intensity VII in Pampas, Huancavelica, Peru with V in Huancavelica, and Ayacucho; IV in San Luis, Lima, Huancayo and Huanta and II-III in Satipo, Junin, Santa Ana, Cusco, and Huanuco, Peru.  Recent such earthquakes have occurred about 150 km north or south of this epicenter. The last within about 150 km of today's epicenter occurred nearly 18 years ago on February 21, 2001 with M 5.6-5.7. Forecast 113629 expected a possible moderately large event in this area was possibly around February 13.

 

O: 14FEB2019 14:33:16  12.1S   74.2W Mw=5.4  EMSC   CENTRAL PERU                 

P: 13FEB2019 113629    11.0S   74.0W 4.0-5.6 ABAAA  Central Peru               

 

The strongest earthquakes in the U.S. or Canada today continued in the swarm which began yesterday with the geomagnetic storm in the Vancouver Island area of Canada. Earthquakes today included the M 5.1 mainshock as well as events of M 4.4, 4.3, 3.7, and 3.5. This summary had noted this series in the previous issue as:

 

"The earthquake swarm in the Vancouver Island, region of Canada began at 0715 with an N 3,2 as the geomagnetic storm was reaching towards maximum and included an M 3.4, 3.5, 4.1 and 4.8-5.1. These events were lightly felt in the epicentral area according to Earthquakes Canada. Earthquakes Canada reported the largest of these at M 5.1. The last earthquake within about 100 km of these epicenters off Vancouver with M>=5.1 in the NEIC database was an M 5.3 more than two years ago on January 7, 2017. Forecast 113591 had expected today's event within about 10 km of the epicenter was likely around February 13." (February 13-14, 2019)

 

 

O: 14FEB2019 04:43:51  50.6N  130.2W ML=3.7  NRCA  195 km W   of Pt. Hardy

O: 14FEB2019 00:54:39  50.5N  130.4W ML=4.3  NRCA  212 km W   of Pt. Hardy

O: 14FEB2019 00:34:40  50.5N  130.3W ML=5.1  NRCA  203 km W   of Pt. Hardy

O: 13FEB2019 22:53:55  50.5N  130.3W ML=4.4  NRCA  207 km W   of Pt. Hardy

O: 14FEB2019 12:29:20  50.5N  130.4W ML=3.5  NRCA  209 km W   of Pt. Hardy       

P: 13FEB2019 113591    50.6N  130.5W 3.0-5.0 AAAAA  British Colombia           

 

The swarm in the Kuril Islands also continued today and was joined by earthquake of moderate magnitude in the Komandorsky Islands and Kamchatka. The events in the Kurils were reported with M 4.9 and 4.6 and forecast within about 100 km in forecast 113579 to occur around February 12.

 

O: 14FEB2019 07:18:50  45.7N  150.3E mb=4.9  EMSC   KURIL ISLANDS                

O: 14FEB2019 18:53:15  45.7N  151.1E mb=4.6  EMSC   KURIL ISLANDS                

P: 12FEB2019 113579    45.0N  152.0E 3.5-5.9 AAAAA  So. Kurils                 

 

The activity in the northwest Pacific in Kamchatka, the Komandorsky Islands and the Kurils was associated with an M 4.9 in the South Georgia Island region of the South Atlantic. This is near the antipode of the Kurils and occurred within an hour of local solar midnight. It was probably enhanced by antipodal and tidal effects. A similar M 4.9 hit this area within about 200 km of this epicenter on January 30 but the last of larger magnitude in this area was an M 5.4 on December 12, 2018 and an M 5.0 on April 4, 2018. Forecast 113403 expected a moderate quake in this region around February 7.

 

O: 15FEB2019 02:56:16  55.2S   31.7W mb=4.9  EMSC   SOUTH GEORGIA ISLAND REGION  

P:  7FEB2019 113403    56.0S   29.0W 4.0-5.8 CABAA  So. Sandwich Islands       

 

The earthquake swarm in the Gulf of California noted in the previous issue of this summary migrated to the south today. There were four moderate quakes in this newly located swarm including events of M 4.0, 4.0 and 4.2. Forecast 113474  

expected this series was likely around February 17. In the previous issue this summary had noted this series as:

 

 

"While not at high latitudes a swarm of light to moderate earthquakes also  occurred in the Gulf of California at the start of the geomagnetic storm and was probably promoted by it. These events of M 3.7, 3.8, 3.9 and 4.1 were the first of this size to be intimately associated with the geomagnetic storm. They occurred within minutes of local solar midnight, a prime time for geomagnetic effects. The last events within about 100 km of this epicenter with M>=4.1 occurred nearly two years ago on May 23, 2017 (M 4.3) and prior to that as an M 4.1 on January 18, 2017. Forecast 113474 had expected this activity within about 25 km was likely around February 17. This area is antipodal to Tropical Cyclone Gelena currently east of Madagascar. This summary had expected some seismic enhancement in the Gulf of California at this time due to focusing of seismic energy at the antipode of TC Gelena" (February 13-14, 2019)

 

O: 14FEB2019 10:52:33  27.4N  111.5W ML=3.6  EMSC   GULF OF CALIFORNIA           

O: 14FEB2019 11:07:22  27.7N  111.8W ML=4.2  EMSC   GULF OF CALIFORNIA           

O: 14FEB2019 10:46:42  27.8N  111.8W ML=4.0  EMSC   GULF OF CALIFORNIA           

O: 14FEB2019 10:49:49  27.8N  111.9W ML=4.0  EMSC   GULF OF CALIFORNIA           

P: 17FEB2019 113474    28.0N  112.0W 3.5-4.9 AAAAA  Gulf of California         

 

GEOMAGNETIC STORM MAY HAVE TRIGGERED SERIES  NEAR VANCOUVER AND KURILS

 

EARTHQUAKE SUMMARY FOR FEBRUARY 13, 2019

 

A new geomagnetic storm occurred today beginning about 0700 UT and was accompanied by a series of moderate earthquake in the high latitudes of the Kuril Islands (M 5.0, 5.0, 5.1, 4.5) and in the region of Vancouver Island, British Columbia, Canada (M 3.6, 3.4, 3.2, 4.1, 5.1). Other locations at high latitudes showing moderate seismicity during this short-lived storm included the South Sandwich Islands (M 4.9, 4.9); Kamchatka (M 5.2) and the Rat Islands, Aleutians (M 4.8). A swarm in the northern Gulf of California also coincided with the start of this geomagnetic storm with magnitudes up to M 4.1. All of these were probably promoted by effects from the geomagnetic storm. The geomagnetic storm is described in this summary as:

 

"The geomagnetic field saw disturbed conditions today. The AP level was 13. High latitude geomagnetic field saw active conditions  with AP at 28. This may be the beginning of a new geomagnetic storm but more likely it is a short excursion which peaked around 1200-1500 UT on February 13. Seismicity along the geomagnetic equator may be slightly enhanced but is more likely to be promoted at high latitudes. The storm began about 0700 UT and was immediately followed by a series of light to moderate earthquake in the Vancouver Island area of B.C. Canada which was near local solar midnight at the time of maximum KP. KP at high  latitudes reached 6 between 0700 and 1400 UT. The only other time high latitude KP has reached level 6 in the past month was during the storm of February 1" (February 13-14, 2019)

 

The swarm in the Kuril Islands northeast of Hokkaido, Japan was unusual and began as the geomagnetic storm was reaching maximum Kp. It included events of M 5.1, 5.0, 5.0 and 4.5. These were not reported felt in the epicentral area.

The Kuril Islands have been relatively quiet in recent months. The last event within about 300 km of today's epicenter with greater magnitude than M 5.1 was an M 5.8 nearly a year ago on March 7, 2018. The last of M 5.1 occurred on December 28, 2018. Forecast 113579 had expected today's activity within about 50 km of these epicenters was likely around February 12.

 

O: 13FEB2019 10:02:55  45.3N  151.4E Mw=5.0  EMSC   KURIL ISLANDS                

O: 13FEB2019 09:25:27  45.3N  151.5E mb=5.0  EMSC   KURIL ISLANDS                

O: 13FEB2019 11:43:58  45.4N  151.4E mb=5.1  EMSC   KURIL ISLANDS                

O: 14FEB2019 04:52:08  45.6N  151.5E mb=4.5  EMSC   KURIL ISLANDS                

P: 12FEB2019 113579    45.0N  152.0E 3.5-5.9 AAAAA  So. Kurils                 

 

The earthquake swarm in the Vancouver Island, region of Canada began at 0715 with an N 3,2 as the geomagnetic storm was reaching towards maximum and included an M 3.4, 3.5, 4.1 and 4.8-5.1. These events were lightly felt in the epicentral area according to Earthquakes Canada. Earthquakes Canada reported the largest of these at M 5.1. The last earthquake within about 100 km of these epicenters off Vancouver with M>=5.1 in the NEIC database was an M 5.3 more than two years ago on January 7, 2017. Forecast 113591 had expected today's event within about 10 km of the epicenter was likely around February 13.

 

O: 13FEB2019 22:53:58  50.7N  130.1W mb=4.1  EMSC   VANCOUVER ISLAND, CANADA REGIO

O: 14FEB2019 00:34:40  50.5N  130.3W ML=5.1  NRCA  W   of Pt. Hardy

O: 13FEB2019 07:51:10  50.5N  130.4W ML=3.6  NRCA  W  of Pt. Hardy

O: 13FEB2019 07:50:01  50.5N  130.5W ML=3.4  NRCA  W   of Pt. Hardy

O: 13FEB2019 07:15:23  50.6N  130.3W ML=3.2  NRCA  W   of Pt. Hardy

O: 14FEB2019 00:34:44  50.7N  130.1W mb=4.8  EMSC   VANCOUVER ISLAND, CANADA REGIO

P: 13FEB2019 113591    50.6N  130.5W 3.0-5.0 AAAAA  British Colombia           

 

O: 13FEB2019 06:34:28  54.8N  160.6E mb=5.2  EMSC   NEAR EAST COAST OF KAMCHATKA 

P: 14FEB2019 113593    56.0N  162.0E 4.0-5.6 ABAAA  E. of Kamchatka            

 

O: 13FEB2019 07:09:11  51.7N  179.6E mb=4.8  EMSC   RAT ISLANDS, ALEUTIAN ISLANDS

P: 15FEB2019 113603    52.0N  177.0E 4.0-5.8 AABAA  Rat Islands                

 

O: 13FEB2019 13:21:02  55.4S   27.2W mb=4.9  EMSC   SOUTH SANDWICH ISLANDS REGION

P:  7FEB2019 113403    56.0S   29.0W 4.0-5.8 CAAAA  So. Sandwich Islands       

 

O: 13FEB2019 05:56:00  57.6S   25.0W mb=4.9  EMSC   SOUTH SANDWICH ISLANDS REGION

P: 14FEB2019 113675    57.0S   25.0W 4.0-5.9 AAAAA  So. Sandwich Islands       

 

While not at high latitudes a swarm of light to moderate earthquakes also  occurred in the Gulf of California at the start of the geomagnetic storm and was probably promoted by it. These events of M 3.7, 3.8, 3.9 and 4.1 were the first of this size to be intimately associated with the geomagnetic storm. They occurred within minutes of local solar midnight, a prime time for geomagnetic effects. The last events within about 100 km of this epicenter with M>=4.1 occurred nearly two years ago on May 23, 2017 (M 4.3) and prior to that as an M 4.1 on January 18, 2017. Forecast 113474 had expected this activity within about 25 km was likely around February 17. This area is antipodal to Tropical Cyclone Gelena currently east of Madagascar. This summary had expected some seismic enhancement in the Gulf of California at this time due to focusing of seismic energy at the antipode of TC Gelena as:

 

 

 

"TC Gelena (13S) continued today east of Madagascar with winds up to 065 kts. It is expected to track to the southeast over the next week. The antipodal region at 26N 107W is antipodal to the Western Mexico and the Gulf of California.  Antipodal triggering may occur in the region of the Gulf of California and Baja, California." (February 11-13, 2019)

 

O: 13FEB2019 07:01:43  28.0N  112.3W ML=3.8  EMSC   GULF OF CALIFORNIA           

O: 13FEB2019 06:57:05  28.1N  112.3W ML=3.7  EMSC   GULF OF CALIFORNIA            

O: 13FEB2019 06:54:06  28.1N  112.3W ML=3.9  EMSC   GULF OF CALIFORNIA           

O: 13FEB2019 06:52:07  28.1N  112.4W ML=4.1  EMSC   GULF OF CALIFORNIA           

P: 17FEB2019 113474    28.0N  112.0W 3.5-4.9 AAAAA  Gulf of California         

 

MODERATELY LARGE QUAKE SHAKES NORTHERN MARIANA ISLANDS

 

EARTHQUAKE SUMMARY FOR FEBRUARY 12, 2019

 

The strongest earthquake in the world today was n M 5.9 in the Northern Mariana Islands. NEIC reported it was felt with intensity II-III in Tinian, Marianas and Tamuning, Guam. No damage or tsunami was expected nor reported. This is the strongest earthquake in the Northern Mariana Islands within about 100 km of this epicenter since an M 7.7 about 75 km south of today's epicenter on July 29, 2016. Forecast 113462 had expected today's event in the Northern Marianas was likely Around February 15.

 

O: 12FEB2019 12:34:15  19.0N  145.9E Mw=5.9  EMSC   MAUG ISLANDS REG, N. MARIANA I

P: 15FEB2019 113462    18.0N  145.0E 4.0-5.4 BAAAA  No. Marianas               

 

The second largest earthquake today was an M 5.1-5.2 in central Vanuatu.  This may have been promoted by Tropical Cyclone Oma which was over the epicenter when the earthquake occurred. This triggering had been expected in previous issues of this report as:

 

 

"TC 15P formed today in the region of northern Vanuatu with winds up to 45 kts. It is expected to track to the southeast over the next several days. Seismic enhancement in the region of Vanuatu could accompany the passage of this storm through the area." (February 11-12. 2019)

 

The last earthquake of M>=5.1 within about 100 km of this epicenter occurred with M 5.1 on November 19, 2018. The last of larger magnitude was an M 5.3 on September 17, 2018. Forecast 113644 had expected this event within about 15 km of the epicenter was likely around February 14.

 

O: 12FEB2019 10:53:06  15.1S  168.1E Mw=5.1  EMSC   VANUATU                      

P: 14FEB2019 113644    15.0S  168.0E 4.0-5.6 AAAAA  Vanuatu Islands            

 

An earthquake of M 4.7 in the Tonga Islands today followed passage of Tropical Cyclone Neil through the epicentral area over the past several days. Forecast 113658 had expected this event within about 100 km was likely around February 13.

 

O: 13FEB2019 04:05:32  23.8S  174.5W mb=4.7  EMSC   TONGA REGION                 

P: 13FEB2019 113658    23.0S  175.0W 4.0-5.6 AAAAA  Tonga Islands              

 

The elevated seismicity along the North Anatolian Fault zone in Turkey to Greece continued today with an M 4.8 and aftershocks of M 4.2 in Central Turkey east of Istanbul. A strong earthquake in the Istanbul area is expected in the near term by many geophysicists and is apparently overdue. The recent activity along the North Anatolian Fault including today's event may be preparatory seismicity to such and event. The last event of M>=4.8 within about 150 km of this epicenter in Central Turkey occurred  more than three years ago on January 10, 2016 (M 4.9) and prior to that an M 5.0 on November 24, 2013. A major M 7.3 event occurred in this area on November 12, 1999 following the great quake in Izmit, Turkey in August, 1999. Forecast 113565 had expected this event was likely within about 50 km of the epicenter around February 13.

 

NEIC reported this earthquake of M 4.8 in northern Turkey was felt with intensity IV in Kizilcahamam, Ankara, and II-III in Incesu, Kayseri, Turkey.

 

O: 12FEB2019 17:23:24  40.6N   33.0E mb=4.2  EMSC   CENTRAL TURKEY               

O: 12FEB2019 17:14:31  40.6N   33.0E mb=4.7  EMSC   CENTRAL TURKEY               

O: 12FEB2019 17:14:30  40.6N   32.9E mb=4.8  ANSS   CENTRAL TURKEY               

P: 13FEB2019 113565    41.0N   33.0E 3.5-5.2 AAAAA  No. Turkey/Black Sea       

 

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

Andreanof Islands, Aleutians, Alaska. This event was not reported felt in this remote area. The last event with M>=4.1 within about 100 km of this epicenter occurred November 21, 2018 with M 4.7. Forecast 113588 had expected a moderate event in this region was likely around February 12.

 

O: 12FEB2019 15:59:39  52.0N  174.4W mb=4.1  EMSC   ANDREANOF ISLANDS, ALEUTIAN IS

P: 12FEB2019 113588    51.7N  175.3W 3.5-5.1 AAAAA  Andreanoff Isls, Aleutians 

 

An event of M 3.4 occurred today west of Parkfield in Central California. NEIC reported this earthquake of M 3.4 in Central California was felt with intensity II-III in the area(s) of San Juan Bautista and Turlock, California. The last event of M>=3.4 within about 50 km of this epicenter was an M 3.5 on January 23, 2018 with M 3.4. The last of significantly larger magnitude was an M 3.9 on May 19, 2015. Forecast 113220 had expected today's event within about 10 km of the epicenter was likely around February 11.

 

O: 12FEB2019 17:27:23  36.3N  120.8W ML=3.4  EMSC   CENTRAL CALIFORNIA            

P: 11FEB2019 113220    36.2N  120.8W 2.5-4.5 AAAAA  Central California         

 

ANOTHER QUIET DAY INCLUDES UNUSUAL M 4.8 IN BAY OF BENGAL

 

EARTHQUAKE SUMMARY FOR FEBRUARY 11, 2019

 

Global seismicity remained at very quiet levels today. No earthquakes of M>5 were recorded. a rarity in global seismicity. An unusual quake in the Bay of Bengal, India was the largest recorded within about 250 km of that epicenter in at least 30 years.

 

An unusual event of M 4.9 occurred in the Bay of Bengal east of India today. NEIC reported this earthquake of M 4.9 in the Bay of Bengal was felt with intensity IV in Chetpet, Tamil Nadu, India and II-III in the area(s) of Tamil Nadu, India at Tinuverkadu, Saint Thomas, Ambattur, Manapakkam, Alandur, Madras and Anakaputhur, India.  This is the strongest earthquake recorded within about 300 km of this epicenter in at least 30 years. The only other event recorded in this area since 1990 with M>=4.0 was an M 4.8 on December 9, 1995.  Forecast 113168 had expected moderate activity southeast of this in early February.

 

O: 12FEB2019 01:32:36  14.3N   86.0E mb=4.9  EMSC   BAY OF BENGAL                

P:  6FEB2019 113168    12.0N   92.0E 4.0-5.4 CCCAA  Andaman Islands            

 

 

The strongest earthquake of the day was an M 5.0 in the region of Samoa. This

occurred following the passage of Tropical Cyclone Neil through the region as noted in previous issues:

 

 

"TC Neil formed today in the region of Tonga with winds up to 45 kts. It is expected to track to the southeast over the next several days. Seismic enhancement in the region of Tonga and Fiji could accompany the passage of this ttorm through the area." (February 10-11, 2019)

 

Forecast 113641 had expected this event was likely in mid-February.

 

O: 11FEB2019 23:26:59  15.8S  172.3W mb=5.0  EMSC   SAMOA ISLANDS REGION         

P: 15FEB2019 113641    16.0S  174.0W 4.0-5.9 BABAA  Tonga Islands              

 

The strongest earthquake in the U.S. or Canada today was an M 4.1 off the coast of Oregon. This event had been expected in this summary to occur at this time in forecast 113570 within about 50 km of this epicenter. It appears to be part of the recent activation of seismicity off the northwest U.S. Earthquakes of larger or equal magnitude last occurred within about 100 km of this epicenter on January 27, 2019 (M 4.5) and July 29, 2018 (M 5.3, 4.4). 

 

O: 12FEB2019 03:52:32  44.6N  129.3W mb=4.1  EMSC   OFF COAST OF OREGON          

P: 13FEB2019 113570    44.1N  128.8W 3.0-4.4 AAAAA  Off Coast of Oregon        

 

QUIET GLOBAL SEISMICITY CONTINUES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 10, 2019

 

Global seismicity continued today at quiet levels. As with the past two days, the largest earthquake in the world today were M 5.0-5.3 and occurred in Southern Iran (M 5.3); Nicaragua/Honduras (M 5.3); Tonga (M 5.1) and Mindanao, Philippines (M 5.2). None of these earthquakes caused reported damage or casualties and most of this activity occurred in area which have been active over the past week.

 

The last earthquake in southern Iran of M>=5.3 within about 200 km of today's epicenter was an M 5.4 on July 22, 2018. The last of significantly larger magnitude was an M 6.1 on May 11, 2013. Forecast 113209 had expected today's event in Southern Iran was likely within about 150 km of the epicenter in early February. NEIC reported this earthquake of M 5.3 in Southern Iran was felt with intensity V in Bandar Abbas, Iran and II-III in the area(s) of Gheshm, Iran; Hasab, Oman; and in the United Arab Emirates at Abu Dhabi (IV) and II-III in Ras Al Khaiman, Ulman, Ash-Shanqaj. 

 

O: 11FEB2019 04:12:35  27.0N   55.7E mb=4.5  EMSC   SOUTHERN IRAN                

O: 10FEB2019 10:54:48  27.1N   55.7E Mw=5.3  EMSC   SOUTHERN IRAN                

P:  4FEB2019 113209    28.0N   57.0E 3.5-5.0 CAAAA  So. Iran/Persian Gulf      

 

The earthquake of M 5.3 in Nicaragua/El Salvador was the strongest within  about 150 km of that epicenter since an M 5.3 on July 27, 2018 and prior to that an M 5.6 on May 6, 2018 Forecast 113186 had expected today's event was likely within this area around February 11.

 

O: 11FEB2019 00:08:48  13.2N   87.7W Mw=5.3  EMSC   GOLFO DE FONSECA, EL SALVADOR

P: 11FEB2019 113186    13.0N   87.0W 3.5-5.1 AAAAA  Nicaragua                  

 

The moderate earthquakes in Tonga of M 5.1 and 4.5 were felt in their epicentral zones. They may have been promoted by Tropical Cyclone Neil which was in the area at the time of these events. This had been anticipated in this summary in  the previous issue as:

 

"TC Neil formed today in the region of Tonga with winds up to 45 kts. It is expected to track to the southeast over the next several days. Seismic enhancement in the region of Tonga and Fiji could accompany the passage of this storm through the area." (February 9-10, 2019)

 

Forecast 113363 expected this activity in early February.

 

NEIC reported this earthquake of M 5.1 in Tonga was felt with intensity II-III in the area(s) of Samoa.  NEIC reported the earthquake of M 4.5 in Tonga was felt with intensity II-III in the area(s) of Apia, Samoa.

 

O: 10FEB2019 13:27:10  15.2S  173.7W mb=5.1  EMSC   TONGA                        

O: 10FEB2019 17:12:55  16.8S  174.5W mb=4.5  EMSC   TONGA                        

P:  3FEB2019 113363    17.0S  173.0W 4.0-5.7 CAAAA  Tonga Islands              

 

The earthquake of M 5.2 in the Philippines was an aftershock of the M 5.9 that

hit the area of northern Mindanao two days ago. PHIVOLCS reported the M 4.2 was felt with intensity III in General Luna, Surigao Del Norte, Philippines.

The M 5.1-5.2 was reported felt with intensity IV in General Luna, Surigao Del Norte, and II in Surigao City, Philippines. Forecast 113180 expected this activity was likely in Northern Mindanao around February 9.

 

O: 10FEB2019 14:33:38   9.9N  126.3E Mw=5.2  EMSC   MINDANAO, PHILIPPINES         

O: 10FEB2019 14:39:02  09.9N  126.5E MS=4.2  PHI  Felt with intensity III

O: 10FEB2019 14:33:32  09.9N  126.5E MS=5.1  PHI  Felt with intensity IV

O: 10FEB2019 16:48:51   9.9N  126.4E mb=4.6  EMSC   MINDANAO, PHILIPPINES        

P:  9FEB2019 113180    11.0N  126.0E 3.5-5.1 AAAAA  Luzon, Philippines         

 

An earthquake of M 3.6 east of Los Angeles, California today was widely felt in the Los Angeles, California area. NEIC reported maximum intensity IV in Hemet, Beaumont,  and II-III in Winchester, Banning, Homeland, Palm Springs, Nuevo, Temecula, Murrieta, Menifee, Sun City, Mountain Center, Cathedral Citym Moreno, Perris, Rancho Mirage, Palm Desert, Yucaipa Wildomar, Redlands, Indian Wells, Lake Elsinore, La Quinto, Riverside, Idyllwild, San Jacinto, Anza, and in general within about 100 km of the epicenter. The last earthquakes within about 50 km of today's epicenter with M>=3.6 occurred as an M 3.7 and 3.8 on November 9, 2018. The last of significantly larger magnitude in the region was an M 4.4 on August 15, 2018, the largest in the area since an M 5.2 on June 10, 2016. Forecast 113254 had expected today's event in this area was likely around February 8.

 

O: 10FEB2019 17:12:24  33.7N  116.8W ML=3.6  EMSC   SOUTHERN CALIFORNIA          

P:  8FEB2019 113254    33.7N  116.1W 2.5-4.4 AAAAA  So. California             

 

The strongest earthquake in the U.S. or Canada today occurred in northwestern Alaska with M 4.8. It was followed by a series of aftershocks of M 3.0-3.5. NEIC reported this earthquake of M 4.8 in Northern Alaska was felt with intensity II-III in the area(s) of Nulato, Alaska. The last earthquake within about 200 km of this epicenter with M>=4.8 occurred more than 10 years ago on October 28, 2008 with M 4.9. An earthquake of M 5.3 hit about 200 km northeast of today's epicenter on October 14, 2018. The only other such event in this region in the past 30 years was an M 5.1 on November 13, 2003.

 

O: 10FEB2019 14:09:43  66.3N  157.2W ML=3.2  EMSC   NORTHERN ALASKA              

O: 10FEB2019 13:35:47  66.3N  157.2W mb=4.8  EMSC   NORTHERN ALASKA              

O: 10FEB2019 22:20:58  66.3N  157.2W ml=3.0  EMSC   NORTHERN ALASKA              

O: 10FEB2019 22:46:48  66.3N  157.2W ml=3.1  EMSC   NORTHERN ALASKA              

O: 10FEB2019 16:56:45  66.3N  157.3W ML=3.3  EMSC   NORTHERN ALASKA              

 

A moderate earthquake of M 4.2 also occurred near Vancouver Island, B.C. Canada. NEIC reported this earthquake of M 4.2 in Vancouver Island, B.C., Canada was felt with intensity II-III in the area(s) of Vancouver,, Canada.  Earthquakes are common in this region, but seldom reach this magnitude level. An M 4.2 occurred near this on January 17, 2019 and an M 4.7 on December 1, 2018 after a lull since August 21, 2018. Earthquakes Canada has substantially more date on seismicity of this region not in the NEIC Database. Forecast 113318 had expected today's event was likely around February 7.

 

O: 11FEB2019 00:02:01  50.7N  130.0W mb=4.2  EMSC   VANCOUVER ISLAND, CANADA REGIO

P:  7FEB2019 113318    50.7N  130.5W 3.0-5.1 BAAAA  British Colombia           

 

GLOBAL SEISMICITY REDUCED

 

EARTHQUAKE SUMMARY FOR FEBRUARY 9, 2019

 

As geomagnetic and tidal effects on seismicity diminished today, global seismicity was also reduced. The strongest earthquakes of the day were of M 5.0-5.2 and occurred in areas where activity has been strong over the past week. These include the Molucca/Halmahera area of Indonesia (M 5.2); northern Chile (M 5.1); Northern Mindanao, Philippines (M 5.2); and the Myanmar-India border (M 5.2).  None of these were damaging but most were felt in their respective epicentral areas. Tropical Cyclone Neil formed in the Tonga/Fiji region where events of M 4.8 and 4.9 occurred today. This storm could encourage elevated seismicity in the Tonga/Fiji region over the next several days.

 

The strongest earthquake in the U.S. or Canada today was an M 4.5 in the Near Islands, Aleutians, Alaska. It was not reported felt in the epicentral area. The last earthquake in the Near Islands within about 200 km of this epicenter with M>=4.5 occurred on October 26, 2018 with M 4.5-4.6 and prior to that on July 10, 2018 also with M 4.6. The last such event in the area with significantly larger magnitude than M 4.5 was an M 5.1 on August 8, 2017. Forecast 11332 had expected a moderate event in this region around February 5.

 

O:  9FEB2019 10:34:00  53.3N  172.7E mb=4.5  EMSC   NEAR ISLANDS, ALEUTIAN ISLANDS

P:  5FEB2019 113322    55.0N  169.0E 4.0-6.1 BBBAA  Near Islands               

 

An outer-rise earthquake of M 3.6 occurred south of the Aleutians in the Fox Islands area today. Outer-rise events can be indicator of stress down slope in the subduction zone and have been used to identify area which may see a large to major upcoming earthquake. Forecast 113321 had expected activity in this area was likely around February 10.

 

O:  9FEB2019 14:18:37  50.8N  170.4W ml=3.6  EMSC   SOUTH OF ALEUTIAN ISLANDS    

P: 10FEB2019 113321    52.4N  169.4W 3.5-5.2 ABAAA  Fox Islands, Aleutians     

 

Seismicity in California today continued at quiet levels. Today was the 48th anniversary of the M 6.7 San Fernando, California earthquake of 1971. The pattern in the area today included events south of Los Angeles, in the Channel Islands and west in the valleys which are similar to precursory activity in the region in February, 1971 and before the Northridge earthquake of January 1994. As earthquakes of M>6 in  the area tend to recur in 20-25 year cycles, it is possible that another significant earthquake in the area is near. Factors which could increase this probability include cyclones in the region east of Madagascar, strong geomagnetic or solar storms,  and strong tidal effects among others.

 

STRONG EARTHQUAKE SHAKES NORTHERN MINDANAO, PHILIPPINES

 

EARTHQUAKE SUMMARY FOR FEBRUARY 8, 2019

 

The strongest earthquake in the world today was an M 5.9 in Northern Mindanao, Philippines. NEIC reported maximum intensity V in Caraga, Philippines at Purok and Pilar; IV in Santa Fe Matalon, Leyte and II-III in Caraga at Union, Carrascal, Dana, Cabadbaran, Butuan and in the Eastern Visayas at Sogod and Maasin. PHIVOLCS reported it was felt with intensity V in General Luna, Del Carmen, Pilar, Carrascal and Mainit, Surigao Del Norte, Cortes and Bayabas, Surigao Del Sur, Surigao City, Talacogon, Agusan Del Sur, Butuan City; IV in Hinatuan, Surigao Del Sur, Tandag City, Gingoog City, Limasawa, San Francisco, Hinunangan, San Ricardo and San Juan, Southern Leyte; III in Palo, Abuyog, Julita, Tanauan, San Miguel, Bato, Leyte, Medina, Tagoloan, Jasaan, and Salay, Minamis Oriental, Kaillangan and Libona, Bukidnon, San Francisco, Agusan del Sur, Nabunturan, Compostella Valley, Cagayan De Oro City; LLigan City, Tacloban City, Davao City; II in Jaro and Leyte, Leyte, Mainbajao, Camiguin, El Salvador City, Manolo, Fortich, Bukidnon,, Bislig City and I in Dipolog City, Philippines. Aftershocks followed and were felt with moderate intensity in the epicentral area. The last earthquake within about 250 km of this epicenter with M>=5.9 occurred two years ago to the northwest on February 10, 2017 with M 6.5.Foredast 113180 had expected a moderate event in the area around February 9.

 

Forecasts 113180 had expected this activity in Mindanao was likely around

February 5-9.

 

O: 08FEB2019 17:01:34   9.8N  126.2E mb=4.6  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 20:10:25   9.8N  126.3E mb=4.7  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 20:37:50   9.8N  126.3E mb=4.8  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 21:10:06   9.8N  126.4E Mw=5.0  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 16:09:25   9.8N  126.4E mb=5.0  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 11:55:06   9.8N  126.5E Mw=5.9  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 15:28:39   9.8N  126.5E mb=4.7  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 12:35:42   9.9N  126.3E mb=4.7  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 21:48:23   9.9N  126.4E mb=4.6  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 17:02:42   9.9N  126.4E mb=4.9  EMSC   MINDANAO, PHILIPPINES

O: 08FEB2019 12:45:38   9.9N  126.4E mb=5.1  EMSC   MINDANAO, PHILIPPINES

O:  8FEB2019 11:55:08   9.8N  126.5E mw=5.9  ANSS   General Luna Philippines     

O: 08FEB2019 11:55:06  09.8N  126.5E MS=5.9  PHI  Felt with intensity V

P:  9FEB2019 113180    11.0N  126.0E 3.5-5.1 ABAAA  Luzon, Philippines         

 

NEIC reported an earthquake of M 5.0 in Northern Mindanao, Philippines was felt with intensity II-III in the area(s) of Union, Caraga and Cagayan, Northern Mindanao, Philippines.

 

O:  8FEB2019 12:29:23  10.0N  126.2E mb=5.0  EMSC   PHILIPPINE ISLANDS REGION    

P:  5FEB2019 113180    10.0N  126.0E 3.5-5.2 BAAAA  Luzon, Philippines         

 

The strongest earthquake in the U.S. or Canada today was an M 3.7 in the Fox Islands, Aleutians, Alaska. It was not reported felt in this remote area. An aftershock of M 3.3 followed about 3.5 hours later. A similar M 3.8 hit the same epicenter on February 7. Forecast 113317 had expected activity in this area in early February.

 

O:  8FEB2019 08:30:02  52.5N  169.8W mb=3.7  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P:  2FEB2019 113317    52.3N  171.3W 3.5-5.3 CAAAA  Andreanoff Isls, Aleutians 

 

O:  8FEB2019 12:04:27  51.9N  170.0W ml=3.3  EMSC   FOX ISLANDS, ALEUTIAN ISLANDS

P:  6FEB2019 113317    52.1N  172.8W 3.5-5.3 AABAA  Andreanoff Isls, Aleutians 

 

Seismicity in California was active in the M 2-3 range today but no events of M>=3 occurred and the swarms in the Landers area and the moderate quake in the northern coastal area discontinued. This may be due to lessening tidal stresses and/or the conclusion of the geomagnetic storm which appear to have helped promote this regional activation.

 

The most unusual earthquake in the U.S. or Canada was an M 3.1 in Ontario, Canada. NEIC reported this earthquake of M 3.1 in Ontario, Canada was felt with intensity II-III in the area(s) of Sudbury, Ontario, Canada.  This is the strongest event within about 100 km of this epicenter since an M 3.1 on September 30, 2015 more than three years ago. The last of larger magnitude

in this area was an M 3.8 on August 5, 2014. Forecast 113047 had expected this event was likely within about 50 km of the epicenter at the end of January or early February.

 

O:  8FEB2019 07:23:37  46.5N   81.2W mb=3.1  EMSC   ONTARIO, CANADA               

P: 30JAN2019 113047    46.0N   81.0W 2.0-4.1 CAAAA  Ohio/Lake Erie             

 

STRONG SWARM EAST OF LOS ANGELES, CALIFORNIA; MODERATE QUAKE SOUTH OF HAWAII

 

EARTHQUAKE SUMMARY FOR FEBRUARY 7, 2019

 

An earthquake of M 4.0 in the area of Southern California near Ludlow east of Los Angeles  was widely felt today. It was followed by a series of lightly felt aftershocks. Several light foreshocks including an M 3.2 also occurred. NEIC reported the mainshock was felt lightly with intensity II-II in Ludlow, Newberry Springs, Joshua Tree, Yucca Valley, Twentynine Palms, Apple Valley, Indian Wells, La Quinto, Ontario and in general within about 100 km of the epicenter. This is the strongest earthquake in this region within about 75 km of this epicenter since February 23, 2016 and February 20, 2016 with M 4.1 and 4.3 respectively. A major earthquake of M 7.3 hit this area near Lander, California on June 28, 1992. Forecast 113259 had expected this activity was likely around February 7. This summary had anticipated regional seismicity would be enhanced at this time as:

 

"The area of Southern California, especially in the area east of Los Angeles ...

Seismicity in the Los Angeles area often increases in January and February. This includes the Northridge quake of  January 16, 1994 (M 6.7) and the San Fernando earthquake of February 9, 1971 (M 6.7). The time for stress to build up in the area may be about 23-25 years, consistent with the possibility of another such event on the horizon. This summary has noted this relation in the past. The Northridge event was preceded by a series of light earthquake south and west of Los Angeles not unlike the series which is now occurring. These may precede a moderate earthquake in the area." (January 31, 2019; February 6-7, 2019)

 

O: 07FEB2019 08:30:03  34.7N  116.3W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:48:20  34.7N  116.3W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:58:04  34.7N  116.3W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 18:02:02  34.7N  116.3W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 04:08:09  34.7N  116.3W Ml=2.0  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 17:09:58  34.7N  116.3W Ml=2.1  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:16:57  34.7N  116.3W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:29:12  34.7N  116.3W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 20:13:37  34.7N  116.3W Ml=2.2  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 00:03:37  34.7N  116.3W Ml=2.3  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 15:56:50  34.7N  116.3W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:56:30  34.7N  116.3W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 00:06:51  34.7N  116.3W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 00:49:41  34.7N  116.3W Ml=2.4  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 04:06:50  34.7N  116.3W Ml=2.5  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 01:52:31  34.7N  116.3W Ml=2.6  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:44:33  34.7N  116.3W Ml=2.7  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 19:32:53  34.7N  116.3W Ml=2.7  EMSC   SOUTHERN CALIFORNIA

O: 08FEB2019 01:57:09  34.7N  116.3W Ml=2.9  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 08:24:37  34.7N  116.3W Ml=3.2  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:14:55  34.7N  116.3W Mw=3.5  EMSC   SOUTHERN CALIFORNIA

O: 07FEB2019 16:41:24  34.7N  116.3W Mw=4.0  EMSC   SOUTHERN CALIFORNIA

O:  7FEB2019 14:16:39  34.7N  116.3W ML=2.7  EMSC   SOUTHERN CALIFORNIA          

P:  7FEB2019 113259    34.6N  116.7W 2.5-4.4 AAAAA  So. California             

 

The largest earthquake in the world today was an M 5.4 in the Southwest Indian Ridge. It was not reported felt in the epicentral area. This epicenter is nearly antipodal to the earthquake in Southern California. Seismic energy from this may change the nature of the swarm in Southern California with the potential to enhance larger events in the region. The last earthquake on the Southwest Indian Ridge within about 200 km of this epicenter with M>=5.4 occurred on July 10, 2018 with M 5.6 and prior to that on July 12, 2016 (M 5.4). Only one event in the area has exceeded M 6.0 in the past 20 years  - an M 6.1 on August 17, 2013.    Forecast 113391 had expected today's event within about 25 km was likely around February 6.

 

O:  8FEB2019 03:11:06  32.8S   57.1E mb=5.4  EMSC   SOUTHWEST INDIAN RIDGE       

O: 08FEB2019 03:11:05  32.8S   57.1E mb=5.4  ANSS   Southwest Indian Ridge"

P:  6FEB2019 113391    33.0S   57.0E 4.0-5.6 AAAAA  So. Indian Ocean           

 

The strongest earthquake in the U.S. or Canada today was an M 4.5 south of Hawaii.  This is the largest earthquake south of Hawaii within about 200 km since an  NEIC reported this earthquake of M 4.6 south of Hawaii  was felt with intensity II-III in the area(s) of Naalehu, Captain Cook, Kealakekua, Honolulu, Kailua, Hilo, Waikoloa, Kamuela, Pahoa and Papaikou, Hawaii.  M 5.2 on June 5, 2013 and prior to that an M 4.8 on October 23, 2009. Forecasts 113199 and 112975 had expected this activity in early February.

 

O:  7FEB2019 19:06:58  18.5N  156.3W mb=4.5  ANSS   HAWAII REGION, HAWAII        

O:  7FEB2019 19:06:58  18.5N  156.3W mb=4.4  EMSC   HAWAII REGION, HAWAII        

P:  4FEB2019 113199    20.3N  155.1W 4.0-5.8 BBAAA  Hawaii area                

P: 30JAN2019 112975    20.1N  156.1W 4.0-5.5 CBAAA  Hawaii area                

 

An earthquake of M 5.4 also occurred in the Molucca and Halmahera, Indonesia region. This continues strong, expected activation of the region associated with the new moon. This had been discussed in the previous issue of this summary as:

 

 

"Strong earthquakes which occurred at the time of the previous new moon on January 6 included an M 5.8 in the Andreanof Islands, Alaska; an M 6.8 deep beneath Brazil; an M 6.6 in the Molucca area of Indonesia and an M 6.3 in Kyushu, Japan. These areas may see additional moderate to strong seismicity at this time." (February 1-6, 2019)

 

The last earthquake within about 200 km of this epicenter with M>-5.7 occurred on January 6, 2019 with M 6.6 and prior to that on April 15, 2018 (M 5.9). Today's event is probably an aftershock of the January, 2019." (February 6-7, 2019)

 

Forecast 113139 had anticipated today's activity was likely within about 50 km around February 7.

 

O:  7FEB2019 10:03:08   2.3N  128.8E mb=5.4  EMSC   HALMAHERA, INDONESIA         

O: 07FEB2019 10:03:08   2.2N  128.8E mb=5.4  ANSS   ENE of Tobelo Indonesia

O:  7FEB2019 09:40:25   2.9N  129.1E ML=4.5  EMSC   HALMAHERA, INDONESIA         

O:  8FEB2019 00:23:47   4.0N  128.6E ML=4.5  EMSC   NORTH OF HALMAHERA, INDONESIA

P:  7FEB2019 113139     3.0N  129.0E 4.0-5.5 AAAAA  Halmahera                  

 

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