1960 Valdivia Earthquake

The 1960 Valdivia earthquake or Great Chilean Earthquake (Spanish: Terremoto de Valdivia/Gran terremoto de Chile) of Sunday, 22 May 1960 is to date the most powerful earthquake ever recorded in Earth's history, rating 9.5 on the moment magnitude scale. It occurred in the afternoon (19:11 GMT, 15:11 local time) and its resulting tsunami affected southern Chile, Hawaii, Japan, the Philippines, eastern New Zealand, southeast Australia, and the Aleutian Islands in Alaska.

The epicenter was near Lumaco (see map) some 570 km (350 mi) south of Santiago, with Temuco being the closest large city, while Valdivia was the most affected city. The tremor caused localised tsunamis that severely battered the Chilean coast, with waves up to 25 metres (82 ft). The main tsunami raced across the Pacific Ocean and devastated Hilo, Hawaii. Waves as high as 10.7 metres (35 ft) were recorded 10,000 kilometres (6,200 mi) from the epicenter, and as far away as Japan and the Philippines.

The death toll and monetary losses arising from such a widespread disaster are not certain. Various estimates of the total number of fatalities from the earthquake and tsunamis have been published, with the USGS citing studies with figures of 2,231, 3,000, or 5,700 killed and another source uses an estimate of 6000 dead. Different sources have estimated the monetary cost ranged from 400 million to 800 million US$ (or 2.9 to 5.8 billion in 2011 dollars, adjusted for inflation).