The 1837 Valdivia earthquake struck south-central Chile on November 17. Together with earthquakes in 1575 and 1737 the earthquake is among the historical predecessors to the great 1960 earthquake. The rupture zone was roughly from Valdivia to the south. It was felt in the cities of Concepción, Valdivia and Ancud. The earthquake was also felt by the crew whaling ships in Guafo Island and Chonos Archipelago. Various landslides were triggered in Chiloé and people are reported to have been thrown to the ground in Valdivia. In contrast in Concepción the shakings were moderate. As reported in various coastal localities the ground rose as result of the earthquake. Decades later while surveying southern Chile’s coasts Francisco Vidal Gormaz was told of islands that been submerged and some that had