The 1737 Valdivia earthquake struck south-central Chile on December 24 with an estimated moment magnitude of 7.5.[2] [3] Together with earthquakes in 1575 and 1837 the earthquake is among the historical predecessors to the great 1960 earthquake.[2] While the overlap in affected areas is significant relative to the 1837 earthquake, the 1737 earthquake may have occurred slightly more to the north.[2]
The earthquake was felt in Concepción but most damage occurred in the towns of Valdivia and Castro, Chiloé Archipelago.[2] In both of these locations churches were destroyed by the earthquake. In addition the Valdivian Fort System and the Royal Storehouse of Valdivia took heavy damage.[2] Landslides occurred next to Villarrica, Calafquén, and Riñihue lakes.[2] Over all this indicates the rupture zone was about 640 km long, with most damage being concentrated in the middle section (Valdivia).[2]
There is no evidence the earthquake would have produced a tsunami.[2]