Analysis On Formation Mechanism And Risk Of Debris Flow In Xueshan River (Basin),Yangbi County,Yunnan Province

Debris flow disaster is one of the major geological disasters in mountainous areas of Yunnan Province.The sudden outbreak of mudslides has often caused serious disasters to the production and life of local people,which has aroused widespread concern.The study of debris flow disasters is the basic work of disaster prevention and mitigation,and has theoretical and practical significance.This paper takes the debris flow in the Xueshan River Basin of Jixian County as the research object.By collecting and sorting out a large amount of literature and field survey data,the geological environment conditions,the characteristics and current status of the debris flow,the formation mechanism of the debris flow,the movement characteristics,and the activity are analyzed.Risk,the development trend of debris flow is predicted.The main research results obtained are as follows:(1)The Xueshan River Basin is located on the left bank of the middle and lower reaches of the Minjiang River.It is the topography of the mid-south steep slope of the middle cut.The terrain is strongly cut and the valleys are developed.The rock and soil in the area are weathered and broken,landslides,collapses,etc.,and the solid loose sources are abundant.The region often has a short-lived and heavy rainstorm climate.The Snow Mountain River Basin has the topography,provenance and water conditions of the debris flow.(2)At present,the debris flow of the Xueshan River is mostly a thin debris flow.The local tributary is a viscous debris flow.The development from small to medium to large is predictable,and the frequency of the explosion changes from low frequency to intermediate frequency.(3)The analysis of the intensity of rainstorms and the ease of debris flow in the region shows that the intensity of heavy rain in the Xueshan River area is large,and the debris flow is currently in the development period(or in the strong years).The environmental dynamics of the basin are unstable,and the possibility of debris flow is relatively high..(4)According to the combination of qualitative and quantitative methods,the Xueshan River debris flow is divided into three areas: extremely dangerous area,dangerous area and affected area,which can provide reference for local debris flow disaster prevention and control work.