Study On The Geological Disaster Susceptibility Based On Multi-Evaluation Models In Jiaocheng County

Jiaocheng County in the study area is located in the transitional position between the middle section of the Lvliang Mountain uplift belt and the Cenozoic graben system.The geological structure is complex,the tectonic activity is intense,the rock and soil mass is broken,the altitude difference is 2080 m,and the mountainous area accounts for 92.4% of the study area.In recent years,the engineering construction in the study area has developed to the mountainous area,and the underground coal mining activities are intense,resulting in frequent landslides,collapses and surface subsidences,which threaten the safety of human life and bring huge obstacles to the construction of new rural areas.The research on the susceptibility of geological disasters can provide a reliable basis for the monitoring and prevention of geological disasters,and has great practical significance for the economic development of the study area and disaster prevention and mitigation.Relying on the project of "Special Investigation of Geological Hazards in Jiaocheng County,Shanxi Province",this paper analyzes the distribution law and influencing factors of geological hazards in the study area based on the investigation of field geological hazards in the study area and collects a large amount of data,and establishes the geological hazards prone to occur in the study area.Based on ARCGIS system,using weighted information model,index of entropy method model,index of sensitivity model,information quantitylogistic regression coupling model,frequency ratio method-logistic regression coupling model and determination coefficient method-logistic regression coupling model,the susceptibility of geological disasters is evaluated by zone,and the six reliability of the model is verified,and the division and comparison are carried out to give the optimal evaluation method and evaluation results in the study area.The specific results are as follows:(1)After field geological disaster investigation and data processing and analysis,it was found that there are 103 geological disaster points in the study area,mainly landslides,collapses,surface subsidences,and a small amount of debris flows and ground fissures geological disasters.In terms of space,geological disasters are mainly concentrated in Tianning Town and Shuiyuguan Town,and are mainly distributed in stripes along rivers,valleys and roads,and ground subsidence is distributed in dense clusters along the goaf;in terms of time,the occurrence of geological disasters is mainly concentrated In the annual spring thawing and summer rainstorms and the ground fissures in the region develop with the activity of the Jiaocheng Great Fault.(2)Based on ARCGIS to draw a vector map of the influencing factors in the study area and analyze the distribution of geological hazards in the study area,it is found that the geological hazards are mainly concentrated on the low and middle mountain slopes with an elevation of 900-1100 m and a slope of 0-35°,mainly in the soft and hard sandy mudstone clastic rock group and sandy clay;rivers,structures,Rainfall and vegetation coverage have a certain influence on the development of geological disasters,but do not play a dominant position;among the factors affecting human engineering activities,geological disasters are distributed linearly along roads and densely distributed along goafs.(3)Through the analysis of the influencing factors of geological disasters,ten evaluation factors for the study of the susceptibility to geological disasters in the study area are determined: rock and soil type,tectonics,landform,elevation,slope,river,goaf,road,rainfall and vegetation.And use weighted information values model(WIV),index of entropy model(IOE),index of sensitivity model(IOS),information values-logistic regression coupling model(IV-LR),frequency ratio method-logistic regression coupling model(FR-LR)and determination coefficient method-logistic regression coupling model(CF-LR)are used to evaluate the susceptibility of the study area.(3)Using the ROC curve to verify the reliability of the results of the six models,the results are: IV-LR > CF-LR> FR-LR> IOE > IOS> WIV;It is determined to use the IV-LR to evaluate the susceptibility of geological disasters in the study area.The reliability of the three coupling methods is about 0.95,and the reliability of the three single methods is about 0.92,and the reliability of the coupling method is greater than that of the single method.Among the six methods,the IV-LR coupling model has the highest reliability,and the IOE has the highest reliability in the single weighting method.The reliability of the coupling method in the two models quantified based on the information method is 0.41 higher than that of the single weighting method;the reliability of the coupling method in the two models quantified based on the frequency ratio method is 0.19 higher than that of the single weighting method;The reliability of the coupled method in the model is 0.34 higher than that of the single weighted method.IV-LR is used to evaluate the susceptibility of geological disasters in the study area,and the obtained accuracy is high.