INFLUENCE OF ACCRETIONARY WEDGE ALONG THE NANKAI TROUGH ON LONG-PERIOD GROUND MOTIONS IN THE CHUKYO AREA

Abstract

This paper describes the influence of the accretionary wedge (hereafter AW) along the Nankai Trough on long-period ground motions in the Chukyo area using the finite difference method. Simulations with AW agree generally well with the observed records in the foreshock occurred in south-east off Mie Prefecture in 2004. Simulations without AW show larger amplitude than the observed records. Based on separation with a barrier, the difference of seismic waves between with and without AW is larger in shallow part of subsurface structures. It’s revealed that AW traps seismic waves from the foreshock and hardly influences on the seismic waves from assumed strong motion generation areas.