Statistics of major Chilean earthquakes recurrence

In this work, we consider historical earthquakes registered in Chile (from 1900 up to 2010) with epicenters located between 19 and 40°S latitude, in order to evaluate the probabilities of the occurrence of strong earthquakes along Chile in the near future. Applying Gumbel’s technique of first asymptotic distribution, Wemelsfelder’s theory and Gutenberg–Richter relationship, we estimate that during the next decade strong earthquakes with Richter magnitudes larger than 8.7–8.9 could occur along Chile. According to our analysis, probabilities for the occurrence of such a strong earthquake range between 64 and 46% respectively. Particularly in the very well known “seismic gap” of Arica, a convergence motion between Nazca and South American plates of 77–78 mm/year represents more than 10 m of displacement accumulated since the last big interplate subduction earthquake in this area over 134 years ago. Therefore, this area already has the potential for an earthquake of magnitude >8.