Risk Assessment Of Geological Hazards In Zhuanghe Based On GIS

Zhuanghe City is located in the northwestern part of Dalian City,Liaoning Province,China.It is a relatively strong mountainous structural uplift and the intersection of the coastal plain.The hilly landforms in the area are fragmented and the landforms are complex.Because of the influence of the natural soil environment and geological tectonic force,as well as complexity of environment of hydrology and meteorology,the geological hazards are extremely serious and have a wide distribution.Judging from the current project construction,it always has a very significant impact on the surrounding environment.Especially in the aspects of blasting and excavation,the above activities have had a serious impact on the local geological environment,and also threatened the ecological balance,further increasing the probability of geological disasters.In order to gain an in-depth understanding of the geological disasters(landslides,landslides and mudslides)in Zhuanghe City and the specific needs of formulating disaster prevention and mitigation policies,this article takes the Zhuanghe City area as the main research object and conducts on-site surveys of the geological disasters in the area.After collecting the relevant data,combining with GIS technology to carry out the exploration,it can finally realize the determination of the local geological disaster distribution law.Two methods,namely the information volume model and the weighted information volume model,are respectively adopted to evaluate the risk degree and impact of geological natural disasters and partition.Based on the obtained geological disasters in various regions of Zhuanghe City,combined with the evaluation of its risk and impact,corresponding suggestions are put forward on this basis.The main purpose is to achieve effective control of the occurrence of geological disasters.The results of this research work mainly cover the following aspects,namely:(1)Through the data collection and preliminary investigation of regional geological disasters in Zhuanghe City,the development and distribution characteristics of collapses,landslides and debris flows in the study area were analyzed and studied,and then the GIS software was used to make the classification and analysis of various impact factors.Hazard point overlay map,statistical analysis of the number of hazard points and hazard point density of various levels of influencing factors,and analysis of the degree of influence of the influencing factors of geological hazards in Zhuanghe City.(2)On the basis of fully understanding and understanding the environmental conditions and background of the study area,9 factors including elevation,slope,aspect,engineering geological rock formation,distance from water system,distance from fault,distance from road,land use,and precipitation Indicators build a risk assessment system.Calculate the information value of each classification level of each influencing factor using the information quantity method,reclassify each influencing factor according to the information value,and use GIS software to perform spatial overlay analysis to obtain the total information value;use the analytic hierarchy process to calculate each index The weight is calculated by using the information amount method to calculate the information amount of each influencing factor and each classification level,using the weighted information amount method to perform GIS weighted superposition to obtain the total information amount value.According to the total information value calculated by the two models,the study area is divided into high,medium,low,and extremely low risk areas.At the same time,determine the area of each area.(3)For the risk assessment results obtained by the two models,the ROC curve and relative risk percentage(HAR)were selected for comparison.The geological hazard risk assessment results obtained by the two models are similar and completely consistent with the actual results.The high-risk areas and medium-risk areas of geological disasters in the study area are mainly scattered in the surrounding areas of the Buyun Mountain and the middle and lower reaches of the Haoyi River.However,the effect of the risk assessment results obtained by using the information volume method model is better than that of the information volume weighting method model.