对2003年巴楚-伽师M_S6.8地震余震近台记录中特殊震相的初步探讨  

Primary Research of Specific Phases Appeared in the Aftershock Sequence of the 2003 Xinjiang M_S6.8 Main Earthquake Recorded by Near Stations

作　　者：黄媛[1] 杨建思[1] 黄磊[2] 

机构地区：[1]中国地震局地球物理研究所,北京市民族大学南路5号100081 [2]廊坊炮兵指挥学院,河北省廊坊065000

出　　处：《中国地震》2006年第3期269-276,共8页Earthquake Research in China

基　　金：地震科学联合基金项目(604012)资助课题。

摘　　要：2003年3月24日发生在我国新疆巴楚-伽师交界处的Ms6．8强烈地震余震序列的近台记录中普遍存在一组特殊震相，该组震相分别出现在Pg波和Sg波的后面，类似于Pg波、Sg波以分组集丛式出现，多为2～3组，且后续震相的能量有所增强。本文通过理论分析并经合成地震图验证，认为该组震相可能是受当地十几公里深的沉积层影响而形成的一种经过多次反射、折射后的叠加波。为便于描述，文中将其分别称为P1、S1震相。A set of specific phases appeared in the aftershock sequence of Mar. 24, 2003 BachuJiashi, Xinjiang Ms6.8 strong earthquake, which were recorded by the near stations. The specific phases followed Pg phase and Sg phase respectively. Most of them presented into 2 - 3 groups, and the subsequent energy became stronger. Through theoretic analysis and synthetic seismogram calculating, we proved that the phases may be a kind of superposed wave reflected or refracted many times, which travel through the lower velocity sediment layer of the quaternary period under lOkm of the earth＇s surface. In order to describe easily, we called the specific phases Pj ,Sj phase temporarily.

关 键 词：特殊震相 双差算法 理论地震图 巴楚-伽师地震 

分 类 号：P315[天文地球—地震学]