【摘要】 陕西省渭河盆地发育了规模不一、成因各异的191条地裂缝,已造成严重的经济损失。首先对研究区的地质环境背景进行分析,探讨了渭河盆地地裂缝灾害的特征和成因分类,选取了评价因子,根据评价模型的特点选取了合理的指标量化方法,并利用层次分析法确定了指标的权重,从而确定了地裂缝危险性评价指标体系;然后以ArcGIS为平台,采集各图层的图形信息和属性信息,使用300m×300m的评价单元,建立研究区的地裂缝灾害空间数据库,实现了查询分析、叠加分析及缓冲区分析的空间分析功能,确定了研究区地裂缝灾害危险性评价数学模型(多级模糊综合评判法);最后运用栅格叠加运算,生成了研究区地裂缝灾害危险性程度分区图,将研究区分为轻度(Ⅰ)、中度(Ⅱ)、中高度(Ⅲ)和高度(Ⅳ)4个等级,得到的地裂缝危险性分区图与实际调查的地裂缝状况吻合较好。更多还原

【Abstract】 As one kind of the major geological disasters,191ground fissures with different cause and scale have developed in the Weihe River Basin,Shaanxi Provice and they have caused serious economic losses.First of all,the geo-environmental background,the causes,classification and characteristics of the ground fissures in the study area of Weihe River Basin were analyzed and evaluation factors were selected.According to the characteristics of the evaluation model,a reasonable index quantification method was selected and the method of AHP was used to determine weights of the indices,therefore,the ground fissure index system of hazard assessment was set up;then as a platform of ArcGIS software,all layers of graphic information and attribute information were collected,the 300m×300mevaluation unit was used,the crack disaster spatial database was established,and the spatial analysis functions of query analysis,overlay analysis and buffer analysis for the study area were established.The mathematical model of hazard assessment(multi-level fuzzy comprehensive evaluation method)of the ground fissures in study areas was determined;Finally,the study area ground fissure disaster hazard degree zoning map was generated,using raster overlay operations.The study area is divided into four grades—mild(I),moderate(II),moderate in height(III)and high(IV),and the dangerous area of the ground fissures partition map is matched to the actual status of the investigation.更多还原