贺兰山东麓断裂南段套门沟—榆树沟段全新世活动与古地震  

STUDY ON HOLOCENE ACTIVITY OF THE SOUTH SEGMENT OF THE EASTERN PIEDMONT FAULT OF HELAN MOUNTAINS BETWEEN TAOMENGOU AND YUSHUGOU

作　　者：杜鹏[1,2] 柴炽章[2] 廖玉华[2] 宋方敏[3] 孟广魁[2] 雷启云[2] 王银[2] 

机构地区：[1]中国地质大学,北京100083 [2]宁夏回族自治区地震局,银川750001 [3]中国地震局地质研究所,北京100029

出　　处：《地震地质》2009年第2期256-264,共9页Seismology and Geology

基　　金：国家发展和改革委员会发改投资"城市活断层试验探测"项目(20041138)资助

摘　　要：贺兰山东麓断裂是银川地堑西侧的重要构造,控制着银川地堑的西侧边界,其最新活动特征是评价未来银川市地震危险性的重要依据。文中在贺兰山东麓断裂南段套门沟—榆树沟段断裂两侧1km范围内1:10000地质填图的基础上,选择在大石头沟两侧进行探槽研究,获得该段断裂在14ka以来共发生了3次古地震事件,分别距今13.8ka、7.9ka和3.0ka,重复周期约为6ka和5ka左右。The eastern piedmont fault of Helanshan Mountains is an important tectonic controlling the west boundary of Yinchuan graben. The south segment of the fault locates right in the west of Yinchuan city, which has a length of about 13.2kin,strikes NNE-NE and dips south-east at an angle of 50°- 80°. The main part of the fault lies between the Ordovician and Quaternary systems, forming the borderline between the hills and diluvium. Parts of the segment of the fault appear in alluvial fans and are displayed as geomorphic scarps. The paper selects the region on the two banks of Dashitou channel to excavate two trenches along the fault based on 1 ： 10, 000 geological mapping of the fault area. The result reveals three events since 14ka BP with the ages of 13.8,7.9 and 3.0ka BP and the recurrence intervals of 6 and 5ka.respectively.

关 键 词：全新世 古地震 套门沟—榆树沟 

分 类 号：P315.2[天文地球—地震学]