HR: 0800h
AN: S41A-0960    [Abstracts]
TI: Dynamic Source Parameters of Characterized Source Model for Strong Ground Motion Prediction
AU: * Iwata, T
EM: iwata@egmdpri01.dpri.kyoto-u.ac.jp
AF: DPRI, Kyoto Univ., Gokasho, Uji, 6110011 Japan
AU: Sekiguchi, H
EM: Haruko.Sekiguchi@aist.go.jp
AF: Active Fault Res. Center, GSJ/AIST, Higashi7, Tsukuba, 3058567 Japan
AU: Miyake, H
EM: hiroe@eri.u-tokyo.ac.jp
AF: ERI, Univ. of Tokyo, Yayoi, Bunkyo, 1000032 Japan
AU: Zhang, W
EM: wenbo@egmdpri01.dpri.kyoto-u.ac.jp
AF: DPRI, Kyoto Univ., Gokasho, Uji, 6110011 Japan
AU: Miyakoshi, K
EM: ken@geor.or.jp
AF: Geores. Inst., Itachibori, Nishi, Osaka, 5500012 Japan
AB: A characterized source model (Irikura and Miyake, 2001; Miyake et al., 2003) for strong ground motion prediction is constructed with the heterogeneous source slip distribution results of the kinematic source inversion. For ground motion simulation, high-frequency radiation level should be constrained. Irikura et al. (2004) give stress drop on the asperity from an idealized slip distribution of the asperity model by Das and Kostrov (1986). Dan et al. (2001) directly constrained that level from the empirical acceleration scaling relation. Here we are trying to obtain stress parameters directly form the kinematic inversion results. We obtained stress parameters by mapping method of spatio-temporal shear-stress distribution on the fault plane from a spatio-temporal slip distribution. They estimated dynamic source parameters averaged over on-asperity and background area from a viewpoint of slip-characterized source model (Iwata et al., 2003; 2004). Until now, they are analyzing seven crustal events and found that (1) average effective stress values, that spans 20-30MPa, of on-asperity area are about 30% larger than the static stress drop values, (2) There is slight depth dependence of the averaged effective stress of on-asperity area, (3) Average effective stress drop of surface ruptured asperity is smaller that of buried asperity, and (4) Average effective stress on the background area is about 5MPa. Those obtained stress parameters can be used for the characterized source model for the broad-band ground motion simulation.
DE: 7209 Earthquake dynamics and mechanics
DE: 7212 Earthquake ground motions and engineering
SC: Seismology [S]
MN: 2004 AGU Fall Meeting