Seismicity Based Maximum Magnitude Estimation of Subduction Earthquakes in Peru

Abstract

In seismic design, intensity parameters that represent seismic demand are commonly used. A probabilistic seismic hazard assessment is an accurate way of assessing seismic demand, based on a set of parameters that represent the seismicity of a region. However, because some regions lack sufficient information, the selection of these parameters can be controversial. In Peru, selecting a maximum earthquake magnitude (M_max) for regional seismic hazard assessments has proven to be a challenging task due to the limited available information concerning of large-magnitude events. This study evaluated the M_max for subduction earthquakes using scaling relationships, empirical evidence, and the extreme value statistics (Kijko and Bayesian) approach. The seismic catalog was updated to February 2022 and divided into 19 subduction seismic sources (5 interface and 14 intraslab). The results showed that the obtained M_max are within the range of M_w 8.7–9.0 for the interface and M_w 7.6–8.1 for the intraslab sources, which unlike the M_max values established in previous regional seismic hazard assessments, are more consistent with the historical and instrumental seismicity and rupture models.