2006年3月31日吉林乾安M5.0余震序列S波分裂研究  

Shear Wave Splitting Analysis of the 31 March 2006 Qian'an M5.0 Earthquake Sequence

作　　者：迟天峰[1] 张新东[2] 郑国栋[1] 朴杰 张宇[1] 

机构地区：[1]吉林省地震局,吉林长春130022 [2]河北省地震局邯郸中心台,河北邯郸056006 [3]延边地震台,吉林延吉133003

出　　处：《华北地震科学》2014年第1期22-26,共5页North China Earthquake Sciences

基　　金：河北省地震科技星火计划项目"利用爆破和近震来校正井下短周期地震计方位角"(项目编号:2013310)

摘　　要：2006年03月31日20时23分，松原市乾安县与前郭县交界处的查干花乡附近（44°36′N，124°03′E）发生5．0级地震，是吉林省近40年来最大一次地震。利用流动台记录到的地震波形资料对乾安地震余震序列进行s波分裂研究。结果表明，S波快波偏振方向的优势取向为NNE，与乾安地震主震的最大主压应力方向偏差较大，与该区区域应力场方向不一致，表明这次地震与区域的构造变化和应力场调整有关。s波分裂时间延时大小受多种因素影响，与S波传播时经过的介质性质关系密切，慢波延迟时间在0．02～0．38S之间变化。The Qian＇an M5.0 earthquake occurred on March 31, 2006 in the center of Songliao basin is the largest earthquake in the last 40 years in Jilin province. This paper analyzes shear-wave splitting using waveform data of Qian＇an M5. 0 earthquake sequence recorded by Lao-Yingtai station of Jilin Digital Seis- mic Network. The results show that the dominant polarization of fast shear wave is in NNE direction and does not consist with the maximum principal compression stress direction, which indicate that the earth- quake is related with the region stress field adjustment. The time delay of shear wave splitting is 0.02 s-0. 38 s. After main shock, the time delay of shear wave splitting dropped apparently which may reflects the release of the principal compression stress.

关 键 词：乾安地震 S波分裂 延迟时间 

分 类 号：P315.3[天文地球—地震学]