内蒙古乌海断陷岗德尔山西麓断裂晚第四纪特征分析  

Late Quaternary Activity Characteristics of Western Piedmont Fault of Gangdeershan in the Wuhai Fault Depression,Inner Mongolia

作　　者：徐东卓[1] 李胜虎 尹海权[1] 叶庆东[1] 夏峰[1] 朱传宝 周海涛[1] 余大新[1] 王磊[1] 郭宝震[1] 董亮[1] XU Dongzhuo;LI Shenghu;YIN Haiquan;YE Qingdong;X1A Feng;ZHU Chuanbao;ZHOU Haitao;YU Daxin;WANG Lei;GUO Baozhen;DONG Liang(The First Monitoring and Application Center, CEA , Tianjin 300180, China;Institute of Oceanology , Chinese Academy of Sciences , Qingdao 266071 , Shandong , China;Institute of Geology and Mineral Exploration of Qinghai Province , Xining 810029 , Qinghai , China)

机构地区：[1]中国地震局第一监测中心,天津300180 [2]中国科学院海洋研究所,山东青岛266071 [3]青海省第三地质矿产勘查院,青海西宁810029

出　　处：《地震工程学报》2018年第1期92-100,共9页China Earthquake Engineering Journal

基　　金：中国地震局监测预报司专项(17A37ZX228);中国地震局地震行业科研专项(201508009);科技部基础性工作专项(2015FY210400)

摘　　要：岗德尔山西麓断裂是乌海断陷的一条控盆边界断裂。通过野外地质调查、构造剖面解析结合浅层物探、地球化学探测,综合对断裂的第四纪活动特征进行分析和研究。结果显示,岗德尔山西麓断裂整体走向NNE,倾角60°~80°,具有成束成带发育特点,是一条全新世活动断裂,表现出以拉张为主的活动特征。The western piedmont fault of Gangdeershan is a basin-controlled fault in the Wuhai fault de-pression.Based on field geological surveys,structural section analysis,and shallow geophysical and geo-chemical explorations,we analyzed the characteristics of the late Quaternary activity of this fault.Through field geological investigation,fault tracing?and structural profile analysis,we determined that the western piedmont fault of Gangdeershan extends north to south,with the northern end at Guanyinsi,Wuhai city,the southern end at Sandaokan,and further south the presence of a hidden fault.The overall strike of the fault is NNE,the dip angle is60.,80.,the fault throw is10?100cm,and it has both bundle formation and zone formation characteristics.The tectonic activity is strong in the study area,and the elevation difference between the sides of the basin and the mountain is about400m.We found the Holocene alluvial sand and gravel deposits to be faulted.The study area is located in the earthquake-free zone and the stress-adjustment transition zone between the northern and southern earthquake areas,and there is a possibility of moderate earthquake activity in the future.Shallow geophysical and geochemical explorations also reveal obvious abnormal changes in the location of faults,and confirm the existence of the fault.The shallow geophysical exploration results show obvious stratigraphic position change and the fault characteristics of bundle formation and zone formation.In addition,most of the faults are high-angle normal faults?and the faults tend to be western.Geochemical surveys mainly employ two methods:soil radon and soil mercury analysis.Based on the above results?we consider the western piedmont fault of Gangdeershan to be a Hol-ocene active fault characterized by tension.

关 键 词：乌海断陷 岗德尔山西麓断裂 晚第四纪 活动特征 

分 类 号：P546[天文地球—构造地质学]