武都-康县断裂新活动性的滑动速率

New Activity and Slip Rate of Wudu—Kangxian Fault

摘要:

探究武都－康县断裂活动的定量数据有助于更深入地了解甘东南地区构造活动和运动转换关系。基于甘肃省陇南市活断层探测与地质填图研究工作，主要通过遥感影像解译、野外地质调查、断错位移测量等基础方法和手段，对发现的陡坎、水系、河流阶地的位错等重点地貌现象进行差分GPS测量（典型位错点以薛家坡及平洛河沈家沟为例），并收集研究区及邻区白龙江一带相关阶地年代，估算出武都－康县断裂西段平均滑动速率约为1.1 mm/a，东段约为1.06 mm/a。根据潜在地震最大震级的评估原则与方法，利用震级M-破裂长度L经验公式，计算得到该地区有发生7级地震的可能性。

Abstract:

The tectonic geometry and kinematic dissipation of the active faults in southeast Gansu can be better understood by exploring the quantitative data of the Wudu—Kangxian fault. Based on the data from surveying and prospecting of active faults and geological mapping in Longnan City, Gansu Province, using a differential GPS, this study mainly investigates the dislocations of scarp, water system, and river terraces discovered by remote sensing image interpretation, field geological survey, fault dislocation measurement, and other basic methods. Taking some typical dislocation points for example, the ages of related terraces in the study area and adjacent Bailongjiang area were collected. The average slip rates of the west and east segment of Wudu—Kangxian fault were estimated to be 1.1 mm/a and 1.06 mm/a, respectively. According to the assessment principle and method of the maximum magnitude of potential earthquakes, using an empirical formula of M-L, it is calculated that an earthquake with magnitude 7 may occur in this area.