Updated ground motion prediction model for Mexican intermediate-depth intraslab earthquakes includingV/Hratios

Abstract

This article presents an updated ground motion prediction equation for pseudo acceleration values from Mexican intermediate-depth intraslab earthquakes at rock sites (National Earthquake Hazards Reduction Program (NEHRP) class B) for the horizontal and the vertical components. The equations were built as functions of magnitude, distance to the fault surface of the earthquake and focal depth, using 23 event recordings (366 records). The database is extended from a previous one used to develop a ground motion prediction equation for intraslab earthquakes, including 7 more events and over 80 accelerograms recorded from 2005 to 2017. The previous model neither included the ground motion parameters from the two significant normal-faulting events occurred in 2017, nor the computing of V/ H ratios. Differences in the predicted ground motion parameters are found. Therefore, an updated attenuation model for intraslab earthquakes is developed for distances up to around 400 km and Mw from approximately 5 to 8.2. The model includes a depth-scaling term with focal depths restricted up to 75 km.