SIMULATION OF STRONG GROUND MOTION BY STOCHASTIC GREEN'S FUNCTION METHOD CONSIDERING 3-D ATTENUATION STRUCTURE

— STRONG GROUND MOTION IN LARGE AREA OF LARGE THRUST EARTHQUAKES —

Abstract

We developed a method to simulate strong ground motions using a combination of the stochastic Green's function and three-dimensional attenuation structures, and succeeded in reproducing the strong motions of the 2003 Tokachi-Oki earthquake (M8) and the 2011 off the Pacific Coast of Tohoku, Japan earthquake (M9). The response spectra using this method well reproduced actual observations of both earthquakes. Our findings show it is necessary to consider the three-dimensional (3-D) S-wave attenuation (Qs) structure in evaluating the ground motion over a broad area.