基于证据权法的北流市南部地质灾害易发性评价

Vulnerability evaluation of geological disasters in south of Beiliu City based on evidence weight method

根据广西北流市南部丘陵区地质灾害的发育特征和分布情况,采用证据权法开展地质灾害易发性评价,选取坡度、坡面曲率、地层岩性、斜坡结构类型、土层厚度、与断裂的距离、结构面、坡脚房屋建设强度、切坡强度9个证据因子,每个证据因子细分证据层,通过计算各证据层的权重和后验概率,并分析各证据因子相关性,最终选取坡度、坡面曲率、地层岩性、土层厚度、切坡强度5个证据因子组合,利用ArcGIS对各证据因子的后验概率值进行叠加,划分出极高、高、中、低易发区。

According to the development characteristics and distribution of geological disasters in the hilly area in the south of Beiliu City,Guangxi,the method of evidence weight is used to evaluate the susceptibility of geological disasters.Nine evidence factors are selected,including slope gradient,slope curvature,formation lithology,slope structure type,soil layer thickness,distance from fracture,structural plane,slope toe housing construction intensity,and slope cutting intensity.Each evidence factor subdivides the evidence layer,and calculates the weight and posterior probability of each evidence layer,and the correlation of each evidence factor is analyzed.Finally,the combination of five evidence factors including slope,slope curvature,formation lithology,soil layer thickness and slope cutting intensity is selected,and the posterior probability values of each evidence factor are superimposed by using ArcGIS to divide high,high,medium and low prone areas.