Darwin’ seismic gap closed by the 2010 Maule earthquake

Abstract

The Maule earthquake (Mw 8.8) that affected south-central Chile on February 27, 2010 was preceded by the 1835 event documented by FitzRoy and Darwin. The relation between both events has remained controversial. Fault slip in 2010 estimated by Lorito et al. (2011) is less than expected from 175 years of strain accumulation, leading them to propose only limited overlap between the 2010 and 1835 events, and that a Mw 7.5–8 event could still strike Concepción. However, Lorito et al.’s model was based on only 6 GPS stations and underpredicts observations from other studies. Here we show that an alternative model based on 169 GPS stations reproduces the data better. Based on a slip deficit map, we suggest the seismic gap opened in 1835 was completely closed by the 2010 event.