基于GIS的四川广安区地质灾害危险性评价

Geological hazard assessment based on GIS in Guang'an,Sichuan province

近年广安区洪水灾害频发诱发大量地质灾害,严重威胁人民的生命财产安全。文章结合广安区地质灾害调查与区划项目,在地质灾害野外实际调查的基础上,选取坡度、坡向、地层岩性、地质构造、水系、降雨作为影响地质灾害发生的评价因子。运用层次分析法确定各评价因子的权重并建立地质灾害危险性指数模型,通过GIS系统的空间分析功能进行栅格运算,完成广安区地质灾害危险性区划。评价结果与实际调查情况基本相吻合,可为今后广安区地质灾害的预测及预防提供了科学参考。

In recent years,a large number of geologic hazards in Guang'an County which were caused by the frequent floods have become a serious threat to people's lives and property security.We select slope,aspect,rocks,geological structure,water system,and rainfall as the influential factors to evaluate the geological hazards by combining the geological hazard survey with district project of Guang'an County,on the basis of the field geological hazard survey.We have established a geological hazard exponential model of geological hazard index,by applying Analytical Hierarchy Process(AHP) and ascertaining the weight of every evaluation factors.What's more,we have finished the risk division of geologic hazards in Guang'an County by applying space analysis function of the GIS system to grid computing.The evaluation result is consistent with the practical investigation.It will provide scientific reference for geological hazard prediction and prevention in Guang'an County.