Spectral Strong Motion Attenuation in Central America

Abstract

A bayesian regression analysis of response spectral ordinates based on 218 digitized strong ground motion accelerograms (largest horizontal component) from Central America, augmented by 62 similar, high-magnitude observations from Guerrero, Mexico, has been performed using the simple linearized ground motion model: lnA = c1 + c2M + c3lnr +c4r = c5S + ln e where M is moment magnitude, r is hypocentral distance, S is zero for rock sites and 1 for soil sites and In£ is a normally distributed error term with zero mean and standard deviation sigma i.e. ln e = N (0, sigma) .