龙泉山西麓山前断裂浅部构造特征及活动性  

Characteristic of Shallow Structure and Fault Activity in Western Piedmont of Longquanshan

作　　者：张威[1] 周荣军[1] 何玉林[1] 刘韶[1] 马超[1] ZHANG Wei;ZHOU Rongjun;HE Yulin;LIU Shao;MA Chao(Sichuan Earthquake Agency,29 Third Section of South-Renmin Road,Chengdu 610041,China)

机构地区：[1]四川省地震局,成都市610041

出　　处：《大地测量与地球动力学》2020年第9期942-946,共5页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震科技星火计划(XH18039Y);四川地震科技创新团队专项(201802,201901);四川省地震科技专项(LY1910)。

摘　　要：为研究龙泉山断裂在西麓山前的空间展布及浅部构造特征,开展了详细的野外地质调查、浅层地震和高密度电法剖面探测等工作,并在钻孔分析和年代学测试数据的基础上,探讨龙泉山山前断裂的活动性。结果表明,龙泉山西麓山前存在隐伏逆冲断裂,倾向南东,为龙泉山西坡断裂的分支,上断点止于全新世粘土层中,属于全新世活动断裂;龙泉山西坡分支断裂的存在证明龙泉山在抬升过程中不断向成都盆地逆冲挤压、扩展,其在龙泉山中段的存在证明龙门山构造应力具有非均匀性,而这种持续的构造变形所引起的地震风险不容忽视。To study the space distribution and the shallow structure characteristic of fault zone in western piedmont of Longquanshan,we carry out a detailed field geological survey,shallow seismic section and high density resistivity detection.We discuss the fault activity based on the drilling analysis and chronological test data.The results show:there is a blind thrust fault in western Longquanshan,which is the branch of Longquanshan fault,and the tendency of the branch fault is SE.The upper fault point stops in the Holocene clay stratum,belongs to the Holocene active fault.The branch fault of Longquanshan tectonic belt is proved in the process of the thrusting from the Longquanshan to the Chengdu basin;its existence also proves that the tectonic stress is with heterogeneity,and we cannot ignore that this continuous tectonic deformation causes the earthquake risk.

关 键 词：青藏高原 龙泉山断裂 浅部构造 断裂活动性 

分 类 号：P315[天文地球—地震学]