STRONG GROUND MOTION SIMULATION AND ITS IMPROVEMENT FOR SITES IN THE METROPOLITAN AREA BY SPGA MODEL DURING THE 2011 TOHOKU EARTHQUAKE

Abstract

This report describes application and modification of the strong-motion pulse generation area (SPGA) model for the 2011 Tohoku earthquake focusing on strong ground motion simulation in the metropolitan area. Equations for Q values and geometrical spreading are modified to take into consideration far distance from seismic faults, though, resulting in overestimation of the Fourier spectra of ground motions. Finally, the rupture pattern of a SPGA off Ibaraki Prefecture is adjusted from the model by Nozu (2012), leading to better consistency with recorded motions in the metropolitan area.