Strong Motion Simulation for the 1944 Tonankai Earthquake Based on the Statistical Green's Function Method and Stochastic Representation of Complex Source Process

Abstract

The precise evaluation of source, path, and site terms in a broad-band frequency range is indispensable for quantitative prediction of strong motions. We have conducted the generalized spectral inversion on strong motions in Japan to delineate both the spectral amplitude and phase characteristics for statistical Green's functions. To predict megathrust earthquakes, we also need to model a kinematic source with stochastic representation of slip and rupture velocity on the fault surface. In this preliminary study we first report the basic features of our statistical Green's functions used for summation. We then show how to construct a kinematic source with distinctive strong-motion generation areas with spatially random slip and rupture velocity variations. After the summation we found that the PGAs and PGVs of synthetics for the Mw8.0 1944 Tonankai earthquake are in good agreement with those of the empirical formula. We see relatively small effects of the random slip distribution.