利用双差地震定位法对民乐-山丹地震序列重新定位

Relocating for the Seismic Sequence Using the Dual-difference of Minle--Shandan Ms6.1 Earthquake Earthquake Location Method

摘要:

利用双差地震定位方法对2003年10月25日民乐-山丹地震序列进行重新定位。结果显示:余震分布的优势方向为NW向,与震源区的区域构造环境相一致;主震位于余震序列的东南端,余震相对于主震的分布并不对称。本次地震为朝NW方向的单侧破裂,在ES方向上破裂遇到了障碍体。

Abstract:

The seismic sequence of Minle--Shandan Ms6.1 earthquake on Oct. 25,2003, is relocated using the dual-difference earthquake location method. The result shows that distribution of aftershocks is in NW direction, consistent with the regional tectonics. The main shock located at southeast end of the range of seismic sequence, and aftershocks are not distributed symmetrically in both side of main shock. It implies that fracturing is from the southeast to northwest and there is K a barrier at southeast of the main shock