1970 Ancash earthquake

Earthquake and resulting avalanche in Peru Ancash earthquake the November 1946 earthquake 1946 Ancash earthquake December 2008 1970 Ancash earthquake 1970-05-31 20:23:29 iscgem796163 796163 Statue of Christ at Cemetery Hill overlooking old Yungay.jpg 31 May 1970 15:23:29 ~45 seconds Peru 7.9 w y 45 km on Normal -9.4 -78.9 inline, title VIIIPlafker Ericksen Fernández Concha 1971 545 0.85 gM 7.9 - 34 km SW of Chimbote, Peru 1970 iscgem796163 0.38 m on Peru 66,794–70,000 dead 50,000 injured The 1970 Ancash earthquake (also known as the Great Peruvian earthquake) occurred on 31 May off the coast of Peru in the Pacific Ocean at 15:23:29 local time 20:23:29 UTC. Combined with a resultant landslide, it is the most catastrophic natural disaster in the history of Peru. Due to the large amounts of snow and ice included in the landslide that caused an estimated 66,794–70,000 fatalities, it is also considered to be the world's deadliest avalanche. Earthquake thumb|USGS ShakeMap showing the earthquake's intensity The undersea earthquake struck on a Sunday afternoon and lasted about 45 seconds. The shock affected the Peruvian regions of Ancash and La Libertad. The epicenter was located 35 km on off the coast of Casma and Chimbote in the Pacific Ocean, where the Nazca plate is being subducted beneath the South American plate. It had a moment magnitude of 7.9 and a maximum Mercalli intensity of VIII (Severe). The focal mechanism and hypocentral depth of the earthquake show that the earthquake was a result of normal faulting within the subducting slab.Dewey J.W. Spence W. 1979 Wyss M. Seismic gaps and source zones of recent large earthquakes in coastal Peru https://books.google.com/books?id=xA4HCAAAQBAJ&q=Seismic+gaps+and+source+zones+of+recent+large+earthquakes+in+coastal+Peru&pg=PA1148 Pure and Applied Geophysics 117 6 1148–1171 10.1007/BF00876212 1979PApGe.117.1148D 140643448 subscription Damage The earthquake affected an area of about 83,000 km2 in the north-central coast and the Sierra (highlands) of the Ancash Region and southern La Libertad Region.30 May 2020 In pictures: Peru's most catastrophic natural disaster https://www.bbc.com/news/world-latin-america-52839770 live https://archive.today/20251216204826/https://www.bbc.com/news/world-latin-america-52839770 16 December 2025 16 December 2025 BBC NewsAugust 2026 Reports of damage and casualties came from Tumbes to Pisco and Iquitos in the east. Damage and panic scenes were reported in some parts of Ecuador. Tremors were also felt in western and central Brazil. It was a system-wide disaster, affecting such a widespread area that the regional infrastructure of communications, commerce, and transportation was destroyed. The earthquake resulted in an estimated $250 million in property damage.NOAA National Geophysical Data Center (2012): Natural Hazard Images Database (Event: May 1970 Huaraz, Peru Images). NOAA National Centers for Environmental Information. doi:10.7289/V5154F01 [16 December 2025] Several towns and villages were nearly completely destroyed as a result of the initial tremors and subsequent landslides. right vertical 230 Pat Nixon in Peru Consuelo Velasco 1970.jpg Pat Nixon hospital Peru C3796-18.jpg U.S. first lady Pat Nixon led American aid efforts after the earthquake. She aided in taking relief supplies to earthquake victims (above) and visited children in hospitals (below). The coastal towns and cities of Chimbote (the largest city in Ancash), Casma, Supe and Huarmey were hit hard; but the Andean valley known as the Callejón de Huaylas suffered the most intense and sweeping damage, with the regional capital, Huaraz, and Caraz and Aija being partially destroyed. Trujillo, the country's third-largest city, and Huarmey suffered minor damage. In Chimbote, Carhuaz and Recuay, between 80% and 90% buildings were destroyed, affecting about three million people. The Pan-American highway was also damaged, which made the arrival of humanitarian aid difficult. The Cañón del Pato hydroelectricity generator was damaged by the Santa River and the railway connecting Chimbote with the Santa Valley was left unusable on 60% of its route. The Peruvian government has forbidden excavation in the area where the town of Yungay is buried, declaring it a national cemetery. The children who survived in the local stadium were resettled around the world. In 2000, the tragedy inspired the government to declare 31 May as Natural Disaster Education and Reflection Day, during which many schools practice an earthquake drill to commemorate the disaster. Landslide 1970 Huascarán debris avalanche The northern wall of Mount Huascarán was destabilized, causing a rock, ice and snow avalanche and burying the towns of Yungay and Ranrahirca. The avalanche started as a sliding mass of glacial ice and rock about 910 m ft wide and 1.6 km (1 mile) long. It advanced about 18 km mi to the village of Yungay at an average speed of 280 to 335 km per hour.Plafker Ericksen Fernández Concha 1971 543 The fast-moving mass picked up glacial deposits and by the time it reached Yungay, it is estimated to have consisted of about 80 million m3 of water, mud, rocks and snow. Yungay Viejo - location of landslide 1970.jpg 1000px Yungay Viejo (2,500 m) as seen from the cemetery hill. The light shaded area shows the location of the landslide (ice, mud, debris avalanche), in which a part of the western flank of Huascaran Norte broke (6,652 m). Yungay Nuevo is behind the shaded area in the center. left See also Peru Earth sciences List of earthquakes in 1970 List of earthquakes in Peru Peru–Chile Trench References ISC-GEM Global Instrumental Earthquake Catalogue (1900–2009) http://www.isc.ac.uk/iscgem/index.php ISC 2014 International Seismological Centre Version 1.05 International Handbook of Earthquake & Engineering Seismology Part A, Volume 81A A List of Deadly Earthquakes in the World: 1500–2000 T. R. Utsu 2002 Academic Press First 978-0124406520 708 PAGER-CAT Earthquake Catalog https://earthquake.usgs.gov/static/lfs/data/pager/catalogs/= September 4, 2009 United States Geological Survey Version 2008_06.1 Peru earthquake of May 31, 1970; Engineering geology observations http://ds.iris.edu/seismo-archives/quakes/1970peru/Cluff1971.pdf L.S. Cluff 1971 Bulletin of the Seismological Society of America 61 3 514 10.1785/BSSA0610030511 1971BuSSA..61..511C 132218116 Sources Geological aspects of the May 31, 1970, Perú earthquake http://ds.iris.edu/seismo-archives/quakes/1970peru/Plafker1971.pdf G. Plafker George Plafker G.E. Ericksen J. Fernández Concha 1971 Bulletin of the Seismological Society of America 61 3 543–578 10.1785/BSSA0610030543 1971BuSSA..61..543P 130140366 External links IRIS SeismoArchive for 1970 Peru earthquake – IRIS Consortium Yungay 1970–2009: remembering the tragedy of The Earthquake – Peruvian Times "In pictures: Peru's most catastrophic natural disaster" BBC News website (accessed and dated 31 May 2020) 796163 Documentary Footage by Texan Relief Workers in Peru, Ancash Earthquake of 1970 on Texas Archive of the Moving Image Ancash earthquake 1970 Category:Earthquakes in Peru Ancash earthquake Ancash Category:1970s tsunamis Category:1970 natural disasters Category:1970s landslides Category:May 1970 in South America Category:1970 disasters in Peru Category:Revolutionary Government of the Armed Forces of Peru