Study On Geological Hazard Investigation And Susceptibility Evaluation Of Heavy Rainstorm Area In Fengjie County

Geological hazards are disastrous geological events formed by various geological processes during the development and evolution of the Earth.The distribution of geological disasters in time and space is governed by both the natural environment and human activities.The occurrence of geological disasters restricts the sustainable development of the ecological environment and social economy,and poses a great threat to the safety of people's lives and property.The research area of this paper is located in the north of Fengjie County in the Three Gorges reservoir area.The geological structure is active in the region,the geological activities are frequent,the topography and geomorphology are complex,human activities are frequent,and geological disasters occur frequently.Therefore,it is of great significance for geological disaster research in this area.In this paper,UAV data is used as the main data source,combined with high-resolution satellite image data,based on geological disaster remote sensing interpretation and field survey verification,using the information quantity model number algorithm and area algorithm to calculate The total information value of each slope unit in the area is determined by the natural breakpoint method to obtain the final disaster susceptibility evaluation level,and the geological disaster evaluation in the area is completed.The specific research results are as follows:(1)The geological disasters in the study area are mainly small landslides and collapse disasters,followed by debris flow on the slopes and relatively few mudslides.The disasters are mainly concentrated on the banks of the Meixi River,especially in the deep-cut areas such as Kangle Town,Gaodianzi and Fairy Town.The Shaxi Temple Formation is the main disaster-preventing stratum in the area.Most of the disasters occur in Zhongshan.In the middle and low mountainous landforms,the slope of the terrain is mostly concentrated between 13° and 36°.The hazard of the hidden danger points is small and medium-sized,and it is basically stable or unstable.(2)The evaluation model of geological hazard susceptibility is constructed in the area.The evaluation of disaster susceptibility results by the number of information method is more accurate than the area information method,and the correct rate is 94.55%.(3)Accordingto the results of geological disaster susceptibility evaluatio n,the study area is divided into four levels: high-prone area,high-prone are a,medium-prone area and low-prone area.The high-prone units(including t hehigh-prone areas and the extremely high-prone areas)are mainly distribut ednear the Meixi River and the perennial tributaries,which may be due to the instability of the slope units caused by the cyclical fluctuations in the water level in the Three Gorges reservoir area.In addition,most of the high-prone units are distributed in human activities,and the transformation and utilization of land by humans has induced geological disasters such asl andslides and collapses.(4)Based on the high-resolution data of the drone and the remote sens ing satellite data,four high-hazard areas of geological disasters were newly discovered,which are the typical disaster concentration area from Fengjie East Interchange Bridge to Yuanjialiang Section,typical disaster concentrati on area from Liangtingzi to Baishui Section,and Wangjiaping Tunnel East.The typical geological disaster concentration area on the side and the typical geological disaster concentration area in the Pingyi Village section provide assistance for local disaster prevention and reduction work.