青藏高原嘉黎断裂晚第四纪运动特征

Late Quaternary Movement Characteristic of Jiali Fault in Tibetan Plateau

通过野外考察与GPS观测数据的综合分析,对嘉黎断裂晚第四纪运动特征得到一些新的认识。嘉黎断裂不是整体右旋走滑断层,其不同构造部位的运动性质和速率具有分段差异特征。以东构造结为界大致分为3段:东构造结以西为嘉黎断裂西北段,东构造结顶端易贡通麦段为嘉黎断裂中段,东构造结东南部分为嘉黎断裂的东南段。西北段为右旋挤压运动,走滑速率3.2～5.8 mm/a;中段弱右旋挤压运动,走滑速率1.3～2.0mm/a;东南段为左旋挤压运动,走滑速率3.7～4.0 mm/a。

By field investigation and the comprehensive analysis of the GPS observation data, some new recognitions were obtained about the late quaternary movement characteristic of Jiali Fault. The Jiali Fault isn＇t an overall dextrall strike-slip. Its movement features and rates are variable in different tectonic parts. Jiali Fault can be divided into three sections by Eastern Himalayan Syntaxis （EHS）. The fault in west area of the EHS is the northwestern segment of Jiali Fault, the fault in Yigong-Tongmai area on the top of the EHS is the middle segment, and the fault in the southeast area of the EHS is the southeastern segment. The northwestern segment is right-lateral compressive movement, with a strike slip rate of 3.2-5.8 mm/a. The middle segment has weak dextral compressive movement, with a strike slip rate of 1.3-2.0 mm/a. The southeast segment is left-lateral compressive movement, with a strike slip rate of 3.7-4.0 mm/a.