1970 Ancash earthquake
earthquake in Peru
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. 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
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 (22 mi) 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.
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. Reports of damage and casualties came from Tumbes to Pisco and Iquitos in the east.
“1970 Ancash earthquake” enters the record as earthquake in Peru. Crown Archives preserves that source wording while asking what Ancash, earthquake and Peru can confirm, complicate or overturn.
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This entry incorporates text from “1970 Ancash earthquake” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.