湖南红层地区滑坡地质灾害致灾因子敏感性分析

Landslide Analysis Based on Susceptibility to Factors Causing Geological Disasters in Red Beds Area of Hunan Province

为了探究滑坡成因机制、揭示滑坡发育规律,以湖南省麻阳苗族自治县为例,选取高程、坡度、地形起伏度、地层岩性、距断层距离等10个因子为致灾因子,基于确定性因数模型开展致灾因子敏感性分析,探究湖南省红层地区滑坡发育特征和成因机制。结果表明:滑坡与土地利用类型、高程和地形起伏度等因子呈现较大的相关性,各因子间的敏感性大小为:土地利用类型>高程>地形起伏度>归一化植被指数>距道路距离>坡度>地层岩性>距河流距离>多年平均降雨>距断层距离;相应因子高敏感区间分别为:土地利用类型为建筑用地、高程[101 m,1394 m)、地形起伏度[47 m,74 m)、归一化植被指数[0.30,0.43)。

In order to explore the formation mechanism of landslides and reveal the development process of landslides,Mayang Miao Autonomous County in Hunan Province was taken as an example,and landslide analysis was conducted for red beds area in Hunan Province based on susceptibility to the selected factors causing disasters,including elevation,slope,terrain ruggedness index(TRI),stratum lithology and distance away from faults,among others.It is found that landslide occurrence is well correlated with several factors,with susceptibility to each factors in the following descending order:type of land use>elevation>TRI>normalized difference vegetation index(NDVI)>distance away from roads>slope>stratum lithology>distance away from rivers>average rainfall during recent several years>distance away from fault,and the corresponding factors with high sensitivity are listed as follows:land used for buildings,elevation[101 m,1394 m),TRI[47 m,74 m)and NDVI[0.30,0.43).