利用GIS方法研究南北地震带和中央造山带交汇区活动断裂与地震的关系

基于地理信息系统(GIS)技术研究南北地震带和中央造山带交汇区断裂带分布与地震活动的关系,对区内16条主要断裂带,以25km为缓冲区宽度,进行叠加,分析各断裂带的地震活动性及其特征.结果表明,主要的发震断裂有西秦岭北缘断裂的西段、礼县-罗家堡断裂西南段以及临潭-宕昌断裂的东南段、文县断裂西南段、虎牙断裂和雪山断裂;虎牙断裂和雪山断裂地震活动性最强,其次是塔藏断裂、礼县-罗家堡断裂以及光盖山-迭山北麓断裂;按震源深度可将研究区划分为4个区域,区内的震源深度由北向南逐渐加大,震源深度剖面图反映了断层的几何形态和力学性质,进一步揭示出了青藏高原向东挤压、物质向东向南逃逸的运动模式.

A GIS Research on the Relationship Between Active Faults and Earthquakes in China North-south Seismic Belt and Central Orogenic System Intersection Zone

This research is done on the relationship between faults and seismicity in China north-south seismic belt and central orogenic system intersection zone based on Geographic Information System (GIS). For each of the 16 faults in this area, a 25kin buffer zone is set with the method of overlay analysis of the seismicity of faults and their characteristics. The result shows a main seismic fault consisting of the northern-edge of West Qinling Fault, south west zone of Lixian-Luojiaban Fault, south east zone of Lintan-Dangchang Fault, south west zone of Wenxian Fault, Huya Fault, and Xueshan Fault. The most active faults are Huya and Xueshan Faults, followed by Tazang Fault, Lixian-Luojiabao Fault and north zone of Guanggaishan-Dieshan Fault. The research zone can be divided into four compressed zones based on earthquake depth, with the hypocenter going deeper from north to south. The sectional view of hypocenter depth can show the geometric shape and mechanical property of the faults, and indicate further the movement model of Tibetan plate, which can serve as a basis for the protection of earthquake and hazard mitigation in this area.