Characteristics and failure mechanism of an ancient earthquake-induced landslide with an extremely wide distribution area

作     者：HUANG Chao LI Yu-sheng YI Shu-jian LIU Kai WU Chun-hao 

作者机构：State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610044 China University of Chinese Academy of Science Beijing 100049 China 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2018年第15卷第2期

页      面：380-393页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 081803[工学-地质工程] 07[理学] 08[工学] 070104[理学-应用数学] 0303[法学-社会学] 0708[理学-地球物理学] 0818[工学-地质资源与地质工程] 0705[理学-地理学] 0815[工学-水利工程] 0706[理学-大气科学] 0816[工学-测绘科学与技术] 0813[工学-建筑学] 0704[理学-天文学] 0833[工学-城乡规划学] 0701[理学-数学] 0713[理学-生态学] 0834[工学-风景园林学（可授工学、农学学位）] 

基　　金：financially supported by the Open Research Fund from the Key Laboratory of Mountain Hazards and Earth Surface Process (Chinese Academy of Sciences) (Grant No.KLMHESP-17-06) the Independent Research Fund from the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology) (Grant No.40100-00002219) 

主　　题：Earthquake-induced landslide Lamuajue landslide Ancient landslide Geologicalfeature Failure mechanism 

摘      要：The Lamuajue landslide is located in Lamuajue village on the tight bank of the Meigu River, Sichuan Province, China. This landslide is an ancient landslide with an extremely wide distribution area, covering an area of 19 km2 with a maximum width of 5-5 km and an estimated residual volume of 3 × 108 ma. The objectives of this study were to identify the characteristics and failure mechanism of this landslide. In this study, based on field investigations, aerial photography, and profile surveys, the boundary, lithology, structure of the strata, and characteristics of the landslide deposits were determined. A gently angled weak interlayer consisting of shale was the main factor contributing to the occurrence of the Lamuajue landslide. The deposition area can be divided into three zones： zone A is an avalanche deposition area mainly composed of blocks, fragments, and debris with diameters ranging from o.i m to 3 m; zone B is a residual integrated rock mass deposition area with large blocks, boulders and ＂fake bedrock＂; and zone C is a deposition zone of limestone blocks and fragments. Three types of failure mechanism were analyzed and combined to explain the Lamuajue landslide based on the features of the accumulation area. First, a shattering-sliding mechanism caused by earthquakes in zone A. Second, a sliding mechanism along the weak intercalation caused by gravity and water in zone B. Third, a shattering-ejection mechanism generated by earthquakes in zone C. The results provide a distinctive case for the study of gigantic landslides induced by earthquakes, which is very important for understanding and assessing ancient earthquakeinduced landslides.