湖南古丈山体滑坡影响因子分析  

Analysis of Impact Factor of Landslide in Guzhang County of Hunan Province

作　　者：沈军 方琼 吴贤云[4] 曹思沁 

机构地区：[1]湖南气象技术装备中心,长沙410007 [2]湖南省气象灾害省重点实验室,长沙410118 [3]湖南省地质环境监测总站,长沙410007 [4]湖南省气候中心,长沙410118 [5]湖南省气象局,长沙410118

出　　处：《气象》2017年第11期1410-1419,共10页Meteorological Monthly

基　　金：国家自然科学基金项目(41305056);国家重点基础研究发展计划(973计划)(2012CB955901)共同资助

摘　　要：为研究湖南省古丈县2016年7月17日群体滑坡的地质环境与降水诱发成因,基于GIS空间分析平台,利用古丈县1:5万地质灾害详查资料、地形地貌、公路河网、坡度坡向、地下水类型、滑坡体与岩土产状关系等空间数据,分析古丈县多种地质环境因子与滑坡事件的影响系数;采用贝叶斯后验概率分析法确定古丈滑坡降水阈值曲线(I-D曲线);基于多要素地质环境因子、临界降水条件及滑坡触发有效雨量综合分析了本次群体滑坡事件的主要成因。结果表明:出现大于当地滑坡阈值的极端降水事件(一定的滑坡降水强度、持续时间和滑坡触发有效雨量)是诱发古丈群体滑坡的主要外源动力,脆弱的岩土结构、滑坡体与岩层产状一致的滑坡类型、公路(铁路)和河网修建对山体切坡的影响、敏感的坡度区间、高风险的坡向区间等地质因子是导致古丈默戎"7·17"滑坡的地质成因,相关研究方法和结论对该地区未来地质灾害预警预报提供了方法和数据支持。This paper analyzes the factors which led to landslide in Guzhang of Hunan Province on 17 July 2016. Based on the GIS space analysis tools, all geological factors contributing to the Guzhang landslide are analyzed by using the geological disaster investigation data with scale of 1-50000, distribution of road and railway as well as the net of small rivers, river banks and aspect of landslides. Using the module of Bayesian inference, and Gibbs Sampling （BUGS）, the parameters of I-D curves are estimated, and the ef- fective rainfall which led to the landslides of Guzhang area is studied. Combining the previous disaster in- vestigation of Guzhang landslides with the analysis result, we get a detailed cause of Guzhang landslides, which is helpful in warning landslides there in future. The analysis about the landslide factor of Guzhang landslide shows us that the extremely heavy rains are the main cause for the landslides, the badly cutting slope condition caused by traffic construction, sensitive slope interval and the high risk of the aspect to the landslide are also the key factors for the 17 July landslide at Morong of Guzhang. The research methods and findings are conductive to the future warning of geological disasters.

关 键 词：滑坡 地质灾害 I-D曲线 降水临界条件 贝叶斯统计分析 

分 类 号：P203[天文地球—测绘科学与技术] P49