Susceptibility evaluation of geological disasters in southern Huanggang based on samples and factor optimization

Taking southern Huanggang as the study area, this paper contrasted the applicability of the two kinds of calculation samples of the number of disasters and the disaster acreage in the information model, and explored the optimization combination of the evaluation factors. The study established the information model and selected the primary evaluation factors according to the engineering geological conditions and the characteristics of geological disasters of the study area. Also, the paper determined the optimization combination of factors with the success rate curve to verify the susceptibility evaluation results by disaster ratio and typical geological disaster. The results show that: ① In the single factor evaluation results, the order of the two AUC values is different but regular. ② The accuracy of each superposition factor evaluation result is above 94.9% of the optimal combination of factors, and the variation range is relatively small. This shows a trend of increase with the increase of the number of factors, but not as much as possible. ③ The results of the two calculation samples show that the high-prone areas are mainly concentrated in the central and northern parts of the study area, and that the low-prone areas are concentrated along the Yangtze River and in the southern part of the study area, consistent with the location of the disaster. ④ Both are the effective calculation samples of information value model in the geological disaster susceptibility evaluation, and the accuracy of the acreage sample is significantly better than that of the quantity sample.