金沙江鲁地拉电站水库区地质灾害易发性评价

摘要

The high mountain gorge areas of Southwest China are areas where geo-hazards are easy-happening. By the research on geo-hazards in typical river sector, we can grasp the regularity of geo-hazards＇ distribution in Jinsha River. This paper takes the reservoir of Ludila Hydropower Station for example, It is based on the analysis of surveying geo- hazards, and carefully considers the internal relations between the river and the geo-hazards using the Logistic regression model and GIS spatial analysis tools. Furthermore, the paper selects 5 key factors （independents） including the surface runoff erod, Engineering geology petrofabric, the shape of river valley, the grade of bank slope, the aspect of bank slope are well contributed to the occurrence of geo-hazards. The predicted result using a logistic model with key factors shows that geo-hazards susceptibility of reservoir is very high. High geo-hazards susceptibility areas accounte for 41% and mainly concentrate in the first sector of reservoir and around Duomei. The result can better illuminate the present features of the reservoir geo-hazards distribution, which can provided the scientific information for prevention of geological and monitor geo-hazards.%西南高山峡谷区是地质灾害高易发区,通过对典型流域段地质灾害的分析研究,能更好地掌握金沙江流域地质灾害的分布规律。本文以鲁地拉电站库区为例,根据野外地质灾害调查分析结果,采用Logistic回归模型和GIS空间分析方法,评价各致灾因子的作用,经过遴选最终选取地表径流冲蚀强度、工程地质岩组、河谷形态、坡度、坡向5个与地质灾害相关性强的因子,进行地质灾害易发性分析,结果表明库区地质灾害易发性程度很高,高易发区占41%,主要集中在库首段及朵美附近,评价结果很好地反映了库区段地质灾害的现状,为有效防治库区地质灾害及后期库区灾害监测提供了科学依据。