THREE-DIMENSIONAL FINITE DIFFERENCE SIMULATION OF LONG-PERIOD GROUND MOTION IN THE KANTO PLAIN, JAPAN

摘要

This study tried to simulate the long-period earthquake motion around the Kanto plain, Japan by using a 3D finite difference technique. First, we investigated characteristics of long-period ground motion observed in the basin during a moderate event with a shallow focal depth. It was found that the long-period motion of a dominant period of 7sec is composed of surface waves. Next, we conducted finite-difference simulation using three existing basin models constructed from seismic refraction data, geology data and microtremor data. The simulations using models from geology data and microteremor data lead similar waveforms to observed data which have a long duration and large amplitude of the dominant a period of 7sec.