基于层次分析法的茂县斜坡地质灾害易发性评价

摘要

茂县是西南深切河谷地区地质灾害的重灾县之一,亦是对区域地质灾害进行特征分析及易发性评价的良好试验基地.在茂县斜坡地质灾害详查及遥感数据解译的基础上,选取高程、地形起伏度、坡形、坡度、地层岩性、水系因子及地质构造7个因素作为评价指标,采用层次分析法对研究区斜坡地质灾害易发性进行评价与区划.结果表明:地质灾害高易发区占地面积约46.1 km2,占10.02%,主要分布于研究区的岷江干流沿岸及其部分支流沿岸等;中易发区面积约149.59 km2,占32.52%;低易发区面积约205.25 km2,占44.62%;非易发区面积约59.06 km2,占12.84%.评价结果与野外调查基本吻合,可为茂县斜坡地质灾害防治及土体规划利用提供依据.%Maoxian county is located in the deep valley region of southwest China with severe slope geological hazards,hence is a good experimental base for characteristic research and susceptibility evaluation of geological disasters.In this research,Analytical Hierarchy Process (AHP) was adopted for the evaluation and zoning of geological disaster susceptibility in the study area based on geo-hazard investigation and remote sensing data interpretation.Seven indices inclusive of height,land relieve,slope shape,gradient,lithology,water,and geological structure were selected as evaluation indicators.Result show that the area of high susceptibility covers 46.1 km2,accounting for 10.02% and distributing mainly along mainstream Minjiang River and some tributaries;the area of medium susceptibility covers 149.59 km2,accounting for 32.52%;and area of low susceptibility is 205.25 km2,taking up 44.62%;and the stable area covers 59.06 km2,comprising 12.84%.The results are consistent with field investigation results in general,and thus could be taken as basis for land use planning and slope geo-hazard prevention and reduction in Maoxian county.