陕西省韩城市地质灾害易发性评价

Evaluation on Geological Hazard Susceptibility in Hancheng City,Shaanxi Province

为研究陕西省韩城市的地质灾害易发性,在野外调查的基础上,利用ArcGIS选取了坡度、坡高、坡向、坡型、距构造距离、工程地质岩组、地貌单元类型与距水系距离8个评价指标,采用信息量模型方法计算各指标在不同分类条件下的信息量值,通过空间叠加分析,将韩城市地质灾害易发性分区划分为高易发性、中易发性、低易发性与非易发性4个分区,其面积占比分别为7.02%、21.17%、41.37%、30.44%,灾点占比分别为24.03%、42.86%、28.57%、4.54%,灾点密度分别为0.3250处/km^(2)、0.1923处/km^(2)、0.0656处/km^(2)、0.0142处/km^(2)。分区结果较好地反映出韩城市地质灾害分布规律,可以为韩城市防灾减灾工作及经济建设提供参考。

In order to study the susceptibility of geological hazards of Hancheng City,Shaanxi Province,eight evaluation indicators are selected with the aid of ArcGIS on the basis of field investigation,including the slope gradient,slope height,slope direction,slope type,distance from geological structure,engineering geology groups of rock masses,geomorphic units and distance from river system.Then,the information value of each indicator under different classification conditions is calculated by using the information volume model method.Through spatial superposition analysis,the susceptibility of geological disasters in Hancheng City is divided into four areas such as high susceptibility,medium susceptibility,low susceptibility,and non-susceptibility.Its area respectively accounts for 7.02%,21.17%,41.37%and 30.43%,and geological hazards account for 24.03%,42.86%,28.57%and 4.54%.The disaster density is 0.3250/km^(2),0.1923/km^(2),0.0656/km and 0.0142/km^(2).The zoning results better reflect the distribution of geological hazards in Hancheng,serving as reference for disaster prevention and mitigation work and economic construction in Hancheng.