HR: 1340h
AN: T33C-1485    [Abstracts]
TI: Quasi-static Analysis of Strike Fault Growth in Layered Media
AU: * KAME, N
EM: kame@geo.kyushu-u.ac.jp
AF: Dept. of Earth and Planetary Sci., Kyushu Univ., Japan, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan
AU: SAITO, S
EM: ssaito@geo.kyushu-u.ac.jp
AF: Dept. of Earth and Planetary Sci., Kyushu Univ., Japan, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan
AU: Oguni, K
EM: oguni@eri.u-tokyo.ac.jp
AF: Earthquake Research Institute, Univ. Tokyo, Japan, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113- 0032, Japan
AB: We study the effects of structural inhomogeneity on the growth of strike-slip faults. A layered medium is considered, made up of an upper layer bounded by a free surface and welded to a lower half-space with different elastic property. Mode III crack is employed as a mathematical model of strike-slip fault, which is nucleated in the lower half-space and then propagate toward the interface. We adopt FEM-β, newly proposed analysis method for failure, to simulate the quasi-statistic crack growth governed by the stress distribution in layered media. Our results show that along planar traces across interfaces a compliant upper layer has significant effects on promoting/suppressing crack growth before/after its extension into the layer and vise versa for a rigid one. This proposes a possibility that surface breaks due to strike faulting could be arrested by deposit layers at the topmost part of the Earth's crust.
DE: 7209 Earthquake dynamics (1242)
DE: 7290 Computational seismology
DE: 8118 Dynamics and mechanics of faulting (8004)
SC: Tectonophysics [T]
MN: 2007 Fall Meeting