汶川8．0级地震触发与余震活动空间分布研究  

Seismic Triggering and the Aftershock Distribution of the Wenchuan M8.0 Earthquake

作　　者：华卫[1,2] 陈章立[3] 李志雄[1] 赵翠萍[1] 王勤彩[1] 

机构地区：[1]中国地震局地震预测研究所,北京100036 [2]广东省地震局,广东广州510070 [3]中国地震局,北京100036

出　　处：《地震》2009年第1期33-39,共7页Earthquake

基　　金：地震行业科研专项(200708026)

摘　　要：文中分析研究了2008年汶川8.0级地震发震构造即龙门山断裂带历史和现今地震活动情况,并计算主震发生后产生的库仑破裂静应力变化,讨论了地震触发与余震空间分布之间的联系。结果表明,龙门山断裂带以虎牙—北川—安县为界分为二段,西南段和东北段在地震活动性方面存在着较大的差异。虽同处一条断裂带上,但两者之间地震活动没有联系。汶川8.0级主震发生之后,在空间上产生的库仑破裂静应力变化具有很明显的分区特征。龙门山断裂带北川至青川之间库仑破裂应力变化值大于+0.05 MPa,主震对该地区后续ML≥5.0余震的发生存在着触发作用。In this paper, we study the historical and current seismicity in the Longmenshan fault where Wenchuan M8.0 earthquake occurred in 2008, and calculate the Coulomb failure static stress changes derived from the mainshock and discusses the relation between the seismic triggering and the distribution of aftershocks. The results show that the Longmenshan fault can be divided by the line marked by Huya-Beichuan-Anxian, and there is a big difference of seismicity in the Southwest and Northeast parts. Seismicity in these two areas has no relation though they belong to the same fault. The Coulomb failure static stress changes in space have obvious segmentation characteristics after the Wenchuan M8.0 mainshock occurred. The values of Coulomb failure static stress changes between Beichuan and Qingchuan in the Longmenshan fault are larger than 0. 05 MPa, indicating seismic triggering effects on the aftershocks occurred later in the area.

关 键 词：汶川地震 应力触发 余震活动 库仑破裂静应力 

分 类 号：P315.7[天文地球—地震学]