1997-1998年伽师强震群震源区应力场特征  

Characteristics of the Stress Field in the Focal Region of Jiashi Strong Earthquake Swarm from 1997 to 1998

作　　者：龙海英[1] 高国英[1] 聂晓红[1] 

机构地区：[1]新疆维吾尔自治区地震局,新疆乌鲁木齐830011

出　　处：《西北地震学报》2007年第2期145-149,共5页Northwestern Seismological Journal

基　　金：新疆维吾尔自治区科技攻关项目(200333116-5)

摘　　要：利用1997-1998年伽师强震群中强地震震源机制系统聚类及震源区应力场反演,得到以下主要结果：（1）伽师强震群中强地震主要以走滑和正断层为主,伽师震源区主压应力方向为NNE或近NS向,与相邻的柯坪块体区域构造应力场方向不一致;伽师强震群的破裂面沿NEE方向,属左旋破裂;（2）4-5级中强地震应力场反演得到最大主压应力轴为NNE向,最小主压应力轴为NWW向,中等主应力轴倾角为65°,比较直立;（3）伽师强震群震源区应力场在强震前后经历了一系列变化。最后对所得结果进行了一定的讨论。Using the system cluster of focus mechanism solutions for moderate-strong earthquakes and the stress field inversion of focal region in the Jiashi strong earthquake swarm from 1997 to 1998, main result as followed are obtained：（1） The Jiashi strong earthquake swarm is characterized mainly by strike-slip and normal fault. The axis of principle compressive stress is oriented mainly to NNE or nearly NS, which is inconsistent with the regional tectonic stress field of the adjacent Kalpin block. The rupture plane of the Jiashi strong earthquake swarm is oriented NEE, belong to left-lateral rupture. （2） From the stress field inversion of moderate-strong earthquakes with M4-5, we obtains that the maximum compressive stress axis is NNE, the minimum one is NWW, the＇dip angle of medium stress axis is 65°, which is upright. （3） The stress field in the focal region had a change process before and after those strong earthquakes. Finally, certain discussion to the result is given.

关 键 词：伽师强震群 震源机制 应力场 系统聚类 

分 类 号：P315.33[天文地球—地震学]