北天山中东段中小地震震源机制解及应力场反演  

The focal mechanism solution and stress field inversion of small and moderate earthquakes along middleeastern part of northern Tianshan Reion

作　　者：龙海英[1] 高国英[1] 聂晓红[1] 李莹甄[1] 沈军[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：《地震》2008年第1期93-99,共7页Earthquake

基　　金：国家支撑项目2006BAC13B01-0102;国家国际合作重点项目2004DFA0005;乌鲁木齐城市活断层探测项目;新疆地震局联合基金(200704)

摘　　要：主要对北天山中东段中小地震震源机制解系统聚类和应力场反演。结果表明,研究区内中小地震震源断错性质主要以逆断层为主,地震主破裂面基本沿NWW向或近EW向,与该区域的NWW向构造带基本一致;研究区内主压应力P轴近NS向,倾角较小,主张应力T轴倾角较大,表明区域应力场主要受NS向水平挤压作用;分区应力场反演结果显示,研究区中、西部最大主应力方向为近NS向,与北天山西段构造应力场方向相一致。The authors mainly analyzed the focal mechanism solution of small and moderate earthquakes, their system cluster and stress field inversion along middle-east segment of northern Tianshan region. The result shows that the rupture characteristics of small and moderate earthquakes in research area were mainly the inverse faulting in nature. The main fracture of earthquakes is basically distributed along NWW or near EW. It is consistent with the regional tectonic belt of NWW. In research area, the main compressional stress P axis is near NS, and the inclination angle is small. The inclination angle of the main tensile stress T axis is big. It indicates that the region stress field is mainly under action of the level extrusion of NS. The result of the stress field inversion in divisional area shows that, in middle and west part of research area, the maximum principal stress is near NS, and it is consistent with the tectonic stress field along western segment in northern Tianshan region.

关 键 词：中小地震 震源机制解 系统聚类 应力场反演 北天山中东段 

分 类 号：P315.7[天文地球—地震学]