陕西省地质灾害易发性综合评价方法初探

Discussion on comprehensive assessment of the susceptibility of geological hazards occurring in Shaanxi Province

陕西省的地质灾害主要包括滑坡、崩塌、泥石流、地面塌陷、地裂缝及地面沉降。论文在总结陕西省107个县(市)地质灾害调查与区划工作的基础上,建立了陕西省地质灾害易发性综合评价指标体系。针对不同灾种选择了25个评价指标作为其易发性的主要影响因素。使用专家——AHP定权法确定各影响因素的权重,并基于GIS构建了综合评价数学模型——综合指数模型,将各指标因子图层按权重进行代数叠加运算,计算出全省地质灾害易发性综合指数。然后根据综合指数的大小,将陕西省地质灾害易发程度划分为高易发、中易发、低易发和非易发四级区。

Geological hazards occurring in Shaanxi province include landslide, landslip, debris flow, land subsidence and ground fissurs. Based on investigation and regionalization of geological hazards in 107 counties （cities） in Shaanxi province, this paper has created a guideline system for comprehensive assessment of the susceptibility of geological hazards in Shaanxi province, from which 25 indexes for assessment of various hazards are selected as major impact factors of the susceptibility. Each factor is asertained by AHP weighing method. A mathematic model for comprehensive assessment, composite index model, has been established by GIS. Calculation of every index factors by algebraical superpostion on the basis of each layer results in the composite indexes for the susceptibility of geological hazards occurring in the province. Then, on the basis of the composite indexes, the susceptibility of geological hazards occurring in Shaanxi Province are regionalized into four liable grades with high, medium, low and non degree.