Source model of the 2005 west off Fukuoka prefecture earthquake estimated from the empirical Green's function simulation of broadband strong motions

Abstract

We estimated strong motion generation area (SMGA) source model which is responsible for broadband (0.2, 0.3-10 Hz) strong motions of the 2005 west off Fukuoka prefecture earthquake and its largest aftershock using the empirical Green's function (EGF) method. The estimated SMGAs are almost corresponding to the large slip area deduced by kinematic waveform inversion. The SMGA rupture for the mainshock propagated mainly upward and toward the northwest with rupture velocity of 3.15 km/s. The size of the SMGA follows the self-similar empirical formula of the asperity size derived by Somerville et al. (1999). The stress drop of the mainshock SMGA is calculated to be 10.7 MPa, which is larger than those of the largest aftershock SMGA and the aftershocks used as EGF. Copyright © The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences; TERRAPUB. © 2006, The Seismological Society of Japan, Society of Geomagnetism and Earth, Planetary and Space Sciences, The Volcanological Society of Japan, The Geodetic Society of Japan, The Japanese Society for Planetary Sciences. All rights reserved.