Local earthquake reflection tomography of the Landers aftershock area

被引:62
作者
Zhao, DP [1 ]
Todo, S [1 ]
Lei, JS [1 ]
机构
[1] Ehime Univ, Geodynam Res Ctr, Matsuyama, Ehime 7908577, Japan
基金
日本学术振兴会;
关键词
seismic tomography; spatial resolution; local earthquakes; reflected waves; Moho discontinuity;
D O I
10.1016/j.epsl.2005.04.039
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
A detailed tomographic image of the crust in the 1992 Landers earthquake (M 7.3) region in southern California is determined by using the first arriving S-waves and the reflected S-waves from the Moho discontinuity (SmS, sSmS) generated by the Landers aftershocks. These data were recorded by two seismic stations that are separated by about 200 kin. The tomographic image obtained has a lateral resolution of 25-35 km (1/6 to 1/8 of the station spacing). This work indicates that crustal reflected waves are very useful to improve the spatial resolution of crustal tomography. Our results show a tendency for areas rich in seismicity to be associated with higher velocities, suggesting that earthquake occurrence is closely related to the in situ structural heterogeneities of the fault zone. (c) 2005 Elsevier B.V. All rights reserved.
引用
收藏
页码:623 / 631
页数:9
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