HR: 17:00h
AN: S14C-05    [Abstracts]
TI: Predictability of Ground Motion: Simulations for the 2003 Tokachi-oki-like Earthquake
AU: * Ando, R
EM: ando@bosai.go.jp
AF: National Research Institute for Earth Science and Disaster Prevention, 3-1 Tennodai, Tsukuba, 305-0006, Japan
AU: * Ando, R
EM: ando@bosai.go.jp
AF: Japan Science and Technology Agency, 4-1-8 Honmachi, Kawaguchi, 332-0012,
AU: Fukuyama, E
EM: fuku@bosai.go.jp
AF: National Research Institute for Earth Science and Disaster Prevention, 3-1 Tennodai, Tsukuba, 305-0006, Japan
AU: Fukuyama, E
EM: fuku@bosai.go.jp
AF: Japan Science and Technology Agency, 4-1-8 Honmachi, Kawaguchi, 332-0012,
AU: Aoi, S
EM: aoi@bosai.go.jp
AF: National Research Institute for Earth Science and Disaster Prevention, 3-1 Tennodai, Tsukuba, 305-0006, Japan
AU: Aoi, S
EM: aoi@bosai.go.jp
AF: Japan Science and Technology Agency, 4-1-8 Honmachi, Kawaguchi, 332-0012,
AU: Hashimoto, C
EM: hashi@eps.s.u-tokyo.ac.jp
AF: University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033,
AU: Hashimoto, C
EM: hashi@eps.s.u-tokyo.ac.jp
AF: Japan Science and Technology Agency, 4-1-8 Honmachi, Kawaguchi, 332-0012,
AU: Matsu'ura, M
EM: matsuura@eps.s.u-tokyo.ac.jp
AF: University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033,
AU: Matsu'ura, M
EM: matsuura@eps.s.u-tokyo.ac.jp
AF: Japan Science and Technology Agency, 4-1-8 Honmachi, Kawaguchi, 332-0012,
AB: We have conducted a joint simulation from the plate subduction to the generation of seismic waves through the earthquake dynamic process. To make a practical estimation of seismic hazard, it is important to evaluate source effects on ground motions based on several earthquake rupture scenarios because the source processes such as rupture directivity and asperity locations leave huge uncertainties comparing to the crustal structures. In this presentation, we focus on the ground motion simulation using the finite difference method with a 3-D crustal structure [Aoi and Fujiwara, 1999] for the 2003 Tokachi-oki earthquake, which occurred in a subduction zone off Hokkaido, Japan. We examined five rupture scenarios to evaluate the rupture directivity effect under a set of dynamic parameters which is given to reproduce the 2003 event. Rupture models are computed by the integral equation method where initial stress and constitutive relation are given by the simulation of plate subduction. The rupture nucleations are assumed, respectively, at a hypocenter of this earthquake in model S, at the shallowest point on the fault area in model A, at its deepest point in model B, at its western end in model C and its eastern end in model D. In all models, seismic moments are the same, which is constrained by the amount of stress drop allowed in the dynamic models. Generally, we observe a clear correlation between amplification of ground motions and the basin structure. In model S, the synthetic seismograms appear to reasonably reproduce the observations. We could observe about factor of 2 differences as the source effect between the models, which is caused by the different rupture scenarios, and the site effect amplifies them at about factor of 5. These variations should be important for the seismic hazard estimation.
DE: 7200 SEISMOLOGY
DE: 7209 Earthquake dynamics (1242)
DE: 7212 Earthquake ground motions and engineering seismology
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
DE: 7240 Subduction zones (1207, 1219, 1240)
SC: Seismology [S]
MN: 2007 Fall Meeting