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采用层次分析法,选取了地层岩性、地质构造、地形地貌、河流、植被、降雨量和人类活动7个一级指标,以及工程地质岩组、地震密度、地震动峰值加速度、坡度、坡向、河流、植被覆盖度、年降水量和公路9个二级指标,通过构建层次结构、构造判断矩阵、层次单排序和一致性检验,确定各评价指标权重。并利用GIS空间分析功能,对各个评价因子进行综合评价,得到陕西省地震次生地质灾害危险性等级区划图。最后,对评价结果进行了验证。研究结果表明:1)陕西省地震次生地质灾害危险性等级可以划分为不危险区、低危险区、中危险区和高危险区4个等级,其中不危险区面积39766.99km~2,低危险区面积74284.39km~2,中危险区面积63636.89km~2,高危险区面积27652.87km~2,所占比例分别为19.37%,36.18%,30.99%和13.47%;2)危险性等级自北而南逐渐增加,陕北黄土高原地震次生地质灾害以中低危险为主,关中渭河平原整体危险性较小,陕南秦巴山地高危区面积最大,高危险区主要分布在陕南秦巴山地和陕北黄土高原地区,尤其是秦巴山地,需要重点防控;3)危险区空间分布具有相对集中性和局地差异性的特点;4)所选取灾害点样本的分布与危险性等级区划具有一致性,86.62%的灾害点落在危险区内,具有一定的可信度,达到了预期的区划效果。
Analytic Hierarchy Process (AHP) is used to select seven first-level indicators of lithology, geological structure, topography, rivers, vegetation, rainfall and human activities, as well as the engineering geological rock group, seismic intensity, peak acceleration of ground motion, slope, , River, vegetation coverage, annual precipitation and nine second-level indicators of the highway. Through the construction of hierarchy, structure judgment matrix, hierarchy order and consistency test, the weight of each evaluation index is determined. By using the spatial analysis function of GIS, the comprehensive evaluation of each evaluation factor is carried out, and the zoning map of the grade of secondary geological hazard in Shaanxi Province is obtained. Finally, the evaluation results were verified. The results show that: 1) The grade of secondary geological disasters in Shaanxi Province can be divided into four grades: non-hazardous area, low-hazard area, medium-risk area and high-risk area, of which the area without danger area is 39766.99km ~ 2, Area of 74284.39km ~ 2, area of middle risk 63636.89km ~ 2, area of high risk 27652.87km ~ 2, accounting for 19.37%, 36.18%, 30.99% and 13.47% respectively; 2) South increased gradually. The secondary geological disasters in the Loess Plateau in northern Shaanxi Province were mainly low-middle and low-level. The overall risk of the Weihe River Plain in Guanzhong was relatively small. The high-risk areas in the Qinba Mountains in southern Shaanxi were the largest. The high-risk areas were mainly distributed in the Qinba Mountains And the northern Shaanxi Loess Plateau, especially the Qinba Mountain, need to be focused on prevention and control; 3) the spatial distribution of the danger zone has the characteristics of relative concentration and local differences; 4) the distribution of the selected disaster points and the classification of the dangerous level Consistency, 86.62% of the disaster points in the danger zone, with a certain degree of credibility, to achieve the desired zoning effect.