ADGEO Advances in Geosciences ADGEO Adv. Geosci. 1680-7359 Copernicus Publications Göttingen, Germany 10.5194/adgeo-22-147-2009 Preliminary re-evaluation of probabilistic seismic hazard assessment in Chile: from Arica to Taitao Peninsula Leyton F. 1 Ruiz S. 2 Sepúlveda S. A. 2 Depto. Ciencias Aplicadas, Universidad de Talca, Curicó, Chile Depto. Geología, Universidad de Chile, Santiago, Chile 14 12 2009 22 147 153 Copyright: © 2009 F. Leyton et al. 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://adgeo.copernicus.org/articles/22/147/2009/adgeo-22-147-2009.html The full text article is available as a PDF file from https://adgeo.copernicus.org/articles/22/147/2009/adgeo-22-147-2009.pdf

Chile is one of the most seismically active countries in the world; indeed, having witnessed very large earthquakes associated with high horizontal peak ground accelerations, the use of probabilistic hazard assessment is an important tool in any decision-making. In the present study, we review all the available information to improve the estimation of the probabilistic seismic hazard caused by two main sources: shallow interplate, thrust earthquakes and intermediate depth, intraplate earthquakes. Using previously defined seismic zones, we compute Gutenberg-Richter laws and, along with appropriate attenuation laws, revaluate the probabilistic seismic hazard assessments in Chile. We obtain expected horizontal peak ground acceleration with a 10% of probability of being exceeded in 50 years, reaching from 0.6 g up 1.0 g in the coast and between 0.4 g and 0.6 g towards the Andes Mountains, with larger values in Northern part of the country. The present study improves our knowledge of geological hazards in Chile, enabling the mitigation of important human and material losses due to large earthquakes in the future.

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