1980 Azores Islands earthquake

Earthquake on Azores Islands, Portugal April 2024 1980 Azores Islands Portugal Azores 1980-01-01 16:42:42 652123 iscgem652123 1980 01 01 yes 15:42:42 6.9 w y ISC-GEM 10 km mi 0 50 km west of Angra do Heroísmo Portugal Azores 38.81 N 27.78 W A small tsunami was registered in Angra do Heroismo Strike-slip VIII–IXSignificant Earthquake: AZORES: TERCEIRA, ANGRA DO HEROISMO https://www.ngdc.noaa.gov/hazel/view/hazards/earthquake/event-more-info/4868 National Geophysical Data Center June 23, 2021 January 1, 1980 73 dead, 400 injured Striking the Autonomous Region of the Azores on 1 January, the 1980 Azores Island earthquake killed 73 people and injured over 400, causing severe damage on the islands of Terceira and São Jorge. Resulting from a strike slip fracture, typical of other historical Azorean earthquakes, and measuring 6.9 on the moment magnitude scale, it also shook the islands of Pico and Faial. In response to the earthquake, Portuguese president António Ramalho Eanes announced three days of national mourning, while relief efforts, initiated by agents of the local Air Force, were soon accompanied by government-supported agencies. Geology Background In 1950, another strong earthquake had rocked the Azores Islands region, and this was the largest earthquake since.Western Newspapers (2 January 1980) Description Volcanic in origin, the Azores lie in a tectonically complex area on either side of the Mid-Atlantic Ridge, between the European, American and African plate boundaries, forming their own microplate.Borges et al. (2007), p.37–54 The 1980 earthquake was the result of movement along a northwest to southeast trending strike-slip fault. After aftershocks from the quake had concluded, a study took place, identifying focal solutions for these small events. The type of faulting responsible for these shocks was similar to that of previous earthquakes around the Azores. For these earthquakes, scientists had determined that the conjugate nodal plane was responsible, seeing shearing in the right-lateral (dextral) direction. All faulting in this area is strike-slip-oriented, and on a rather large scale.Regional stresses along the Eurasia-Africa plate boundary derived from focal mechanisms of large earthquakes Pure and Applied Geophysics 136 4 433–448 10.1007/BF00878580 1990 Udías, Agustín Buforn, Elisa 1991PApGe.136..433U 129343125 Because of this research, information now points towards Azores volcanism being controlled by earthquake movement.Aftershock sequence of the January 1, 1980, earthquake and present-day tectonics in the Azores Geophysical Research Letters Hirn, A. Haessler, H. Trong, P. Hoang Wittlinger, G. Victor, L. A. Mendes 7 7 501–504 10.1029/GL007i007p00501 1980GeoRL...7..501H July 1980 Damage and casualties The earthquake that struck the Azorean islands was 6.9 w y. It caused considerable damage on three separate islands (Terceira, São Jorge Island, and Graciosa),https://earthquake.usgs.gov/learning/today/his_01_01.php Today in Earthquake History: January 1 United States Geological Survey February 18, 2009 September 1, 2009 https://web.archive.org/web/20080601164106/http://earthquake.usgs.gov/learning/today/his_01_01.php June 1, 2008 destroying several buildings.https://pqasb.pqarchiver.com/latimes/access/665466312.html?dids=665466312:665466312&FMT=ABS&FMTS=ABS:AI&type=historic&date=Jan+02%2C+1980&author=&pub=Los+Angeles+Times&desc=Quake+Hits+Azores+Islands%3B+at+Least+52+Die%2C+300+Hurt&pqatl=google Quake Hits Azores Islands; at Least 52 Die, 300 Hurt Los Angeles Times January 2, 1980 September 1, 2009 October 22, 2012 https://web.archive.org/web/20121022114432/http://pqasb.pqarchiver.com/latimes/access/665466312.html?dids=665466312:665466312&FMT=ABS&FMTS=ABS:AI&type=historic&date=Jan+02,+1980&author=&pub=Los+Angeles+Times&desc=Quake+Hits+Azores+Islands%3B+at+Least+52+Die,+300+Hurt&pqatl=google dead According to local reports, roughly 70% of the houses on Terceira were completely demolished, including the historic quarter of the island capital, Angra do Heroísmo. In general, public buildings such as churches remained intact, while several buildings caved in on themselves. Public utilities such as electricity and water, were reported cut in several areas. Initially, the number of fatalities was set at 52. It was later revised to 61 and finally to 72.Ferreira Marta Leite Sismo dos Açores em 1980. A história do terramoto mais destrutivo dos últimos 200 anos em Portugal https://observador.pt/2018/02/12/sismo-dos-acores-em-1980-a-historia-do-terramoto-mais-destrutivo-dos-ultimos-200-anos-em-portugal/ 2024-04-18 Observador pt-PTMendes Ana Isabel 2014-03-08 Memórias do sismo de 1980 nos Açores reunidas num “site” https://www.publico.pt/2014/03/08/ciencia/noticia/memorias-do-sismo-de-1980-nos-acores-reunidas-num-site-1627466 2024-04-18 PÚBLICO pt Additionally, the injuries were set at 300,https://select.nytimes.com/gst/abstract.html?res=FB0E1FF73F5410728DDDAB0894D9405B8084F1D3 Earthquake Kills 52 in the Azores The New York Times January 2, 1980 September 1, 2009 but this was also revised to more than 400. At least 20,000 people were left homeless.Azores' Exiles Forsake U.S. And Go Home October 3, 1982 The New York Times https://www.nytimes.com/1982/10/03/world/azores-exiles-forsake-us-and-go-home.html Minor damage was recorded at Pico and Faial islands. No fatalities were recorded at the Lajes Field air base, nor any major damage. Relief efforts and response United States Navy and Air Force personnel stationed at Lajes functioned as disaster relief workers, sheltering as many as 150 families.http://www.lajes.af.mil/library/factsheets/factsheet.asp?id=4004 Lajes Field History – Humanitarian Efforts, 1980s and 1990s Lajes Air Field September 19, 2009 dead https://web.archive.org/web/20080507105531/http://www.lajes.af.mil/library/factsheets/factsheet.asp?id=4004 May 7, 2008 Portuguese Air Force members brought supplies to earthquake victims, while a Portuguese Navy João Coutinho corvette 1 transported medical officials to the island. The Portuguese president, António Ramalho Eanes, flew in on a plane accompanied by medical personnel and supplies (such as bedding). Local officials including policemen and volunteer firemen cleared roads for relief supplies and transports. Responding to the situation, these officials were also involved in looking for survivors in the rubble. Soon after, tents were erected to replace the destroyed or unsafe homes for approximately 200 families of the islands. Portable homes were constructed by the People to People International project fund, resulting in 100 shelters. Three days of national mourning were declared by Eanes. Following the relief efforts, 19 seismographic stations were installed to monitor seismic activities. Eleven of these were used to monitor earthquake activity, while the other eight also record information on the island's geothermal areas.Lee Hung 2003 1415 The earthquake forced hundreds of people to leave the country for the United States. It occurred during a period of several major natural disasters in which many residents of the island left; in 1975, 8,000 residents left. In 1981, however, just 2,500 people left the island. Analysis and current situation Later studies of the events leading up to the tragedy found several factors contributing to the extent of the damage. A. Malheiro (2006) linked five major causes to damage from these earthquakes. The buildings most damaged by the earthquake were near fault lines on top of loosely packed soil. They tended to be of poor construction and did not conform to proper building code, nor had they been adequately examined.Geological hazards in the Azores archipelago: Volcanic terrain instability and human vulnerability August 2006 156 1–2 158 Journal of Volcanology and Geothermal Research Malheiro, A. 2006JVGR..156..158M 10.1016/j.jvolgeores.2006.03.012 The area around the Azores remains active. Threats from earthquakes and landslides remain. See also List of earthquakes in 1980 List of earthquakes in Portugal List of earthquakes in the Azores References Notes Sources International handbook of earthquake and engineering seismology, Part 2 Kan Lee William Hung International Association of Seismology and Physics of the Earth's Interior's 2003 Caracterização da sismicidade histórica dos Açores com base na reinterpretação de dados de macrossísmica: contribuição para avaliação do risco sísmico nas ilhas do Grupo Central Silva M University of the Azores, Departamento de Geociências 2005 Ponta Delgada Portuguese 146 Monografia 10 anos após o sismo dos Açores de 1 de Janeiro de 1980 Madeira J. A. Ribeiro C.S. Oliveira A.R. Lucas J.H. Guedes O regime tectónico nos Açores 1 Secretaria Regional da Habitação e Obras Públicas (Terceira); Laboratório Nacional de Engenharia Civil (Lisbon) 163–174 Portuguese 1992 http://www.cvarg.azores.gov.pt/Cvarg/CentroVulcanologia/geologiaacores/SD+-+01011980.htm Sismo de 1 de Janeiro de 1980 CVARG 2010 Centro de Vulcanologia e Availação de Riscos Geológicos 2010-04-09 https://web.archive.org/web/20120305153207/http://www.cvarg.azores.gov.pt/Cvarg/CentroVulcanologia/geologiaacores/SD+-+01011980.htm 2012-03-05 dead Borges J.F. Bezzeghoud M. Buforn E. Pro C. Fitas A. 2007 The 1980, 1997 and 1998 Azores earthquakes and some seismo-tectonic implications Tectonophysics 435 1–4 37–54 10.1016/j.tecto.2007.01.008 2007Tectp.435...37B 10174/6383 free Regional stresses along the Eurasia-Africa plate boundary derived from focal mechanisms of large earthquakes Birkhäuser Basel Pure and Applied Geophysics 136 4 433–448 10.1007/BF00878580 1990 Udías, Agustín Buforn, Elisa 1991PApGe.136..433U 129343125 https://news.google.com/newspapers?id=w4ALAAAAIBAJ&sjid=tVMDAAAAIBAJ&pg=7129,21775&dq=1980+azores+island+earthquake Earthquakes devastates Azores Island Western Newspapers Inc. 2 January 1980 1 September 2009 External links 652123 Azores Islands Earthquake, 1980 Azores Islands Earthquake, 1980 Category:Earthquakes in Portugal Category:January 1980 in Europe Category:Strike-slip earthquakes