Fractal Analysis And Hazard Estimation Of Landslides Triggered By The 2012 Xinyuan And Hejing Ms6.6 Earthquake In Xinjiang

Seismic landslide is an important secondary disaster of earthquake.These landslides seriously threaten people's personal and property security,and seriously affect the future development trend of regional geological disasters.Therefore,seismic landslide has attracted the general attention of the disaster researchers.This paper analyzes the spatial distribution characteristics of seismic landslides and the relations and laws between them and various influencing factors,uses the variable dimension fractal theory to quantitatively analyze the sensitivity of seismic landslides to various factors,which has a deep and macro grasp of the development law of seismic landslides,The information model was used to evaluate the landslide risk in the study area,and has an important reality for disaster prevention and mitigation and environmental protection significance.On June 30,2012,the Ms6.6 earthquake occurred at the junction of Hejing County and Xinyuan County in Xinjiang triggered a large number of seismic landslides.In this paper,based on the GIS platform,combined with high-resolution remote sensing image,geological topography and hydrology and other basic data,the seismic landslides in the study area were studied in depth,and the following results were obtained:1.Based on the GIS platform,the high-resolution satellite remote sensing images of Rapideye in Germany and IKONOS in the United States before and after the earthquake were interpreted visually,and the detailed and comprehensive seismic landslides catalogue map was drawn.Interpretation results show that the earthquake induced at least 453 landslides,and that the total area of the earthquake landslides is 0.66km2,which is 0.01% of the total area of the study area.2.The terrain factors such as elevation,slope,direction,position,water system,curvature,topographic relief,geological factors such as formation lithology and fracture,seismic factors such as peak acceleration of ground motion,etc.are selected,and a total of 10 seismic landslide influencing factors are selected.The relationship and law between the spatial distribution of landslides and the influencing factors are studied.The results show that landslides are greatly controlled by the terrain factors.The high-density area of the earthquake landslides is mainly distributed on the high and steep slopes on both sides of the north-east extending valley.3.The sensitivity of the distribution of earthquake landslides to 10 influencing factors is studied by using the variable dimension fractal method.The results show that the landslides and the 10 influencing factors all have the variable dimension fractal characteristics.In addition to the water system,the other 9 factors all have the second-order variable dimension relationship.The relationship between the fractal dimension values of each influencing factor is obtained: elevation > aspect > slope > terrain curvature > distance from fracture > PGA > terrain Undulation > formation lithology > slope position > distance from water system.4.Fractal theory and AHP weighted information model are used to evaluate the landslide risk in the study area.The range of the information value of the study area is:-1.1656-0.7958.The study area is divided into five areas by natural breakpoint method: extremely high risk area,high risk area,medium risk area,low risk area and extremely low risk area.AUC = 80.77 verified by the evaluation result curve shows that the accuracy of the evaluation result is 80.77%,and the evaluation result is reliable.