Research On Disaster Geology Based On Comprehensive Analysis Of Remote Sensing

Geological disasters refer to the catastrophic geological events that occur under the influence of natural factors or human factors and cause losses to human life and property.Common geological disasters include landslides,debris flows,collapses,ground fissures,land subsidence and land subsidence,which are widely distributed in various countries in the world and restrict the development of social economy.China is a country with frequent geological disasters.The main types of geological disasters are earthquakes,collapses,landslides,debris flows,ground collapses and ground fissures.These geological disasters cause serious casualties and economic losses.In recent years,China's remote sensing industry has entered a vigorous development stage.With the continuous development of remote sensing technology,remote sensing technology has become one of the effective means of geological disaster monitoring.With the joining of GIS,GPS and RS,the study of geological disaster is no longer limited to the qualitative study,but also gets rid of the complicated steps of field investigation.Because geological disaster events are caused by many factors and have a high degree of suddenness,people cannot take effective preventive measures before geological disasters occur,and geological disasters will cause great losses to human life and property.China is a country with frequent geological disasters.The economic losses caused by geological disasters to our country each year are more than 5% of the gross national product.It can be seen that the interpretation,monitoring and evaluation of geological disasters are indispensable.With few and urgent tasks,only by fully understanding the factors induced by geological disasters,the mechanism of occurrence,deformation laws and deformation characteristics can we effectively evaluate the risk of geological disasters,thus effectively preventing and preventing high-risk areas Early warning to reduce its damage to people's lives and property.In this paper,based on the two-phase DEM data of 2009 and 2016 and the remote sensing images of Coqin County and Gaize County in the Ali Region of Tibet as the data basis,through the analysis of the slope of the single-phase DEM data,the differential analysis of the multi-phase DEM data is carried out to identify the topographic and surface changes of Gaize County and Coqin County in the Ali region of Tibet,and then superimposed image information to identify the type of geological hazards,and the expression of the disaster extraction results,that is,to complete the map of geological hazards in Coqin County and Gaize County;then through the study area The known disaster point is a sample,and through the expansion tool SDM of ArcGIS,combined with the sample of the known disaster point,the weight value of each factor is calculated by the evidence weight method,and finally the posterior probability is calculated by the weight value and each evidence factor.According to the posterior probability value,the geological hazard risk of Cuqin County and Gaize County in Ali area is graded,and two geological hazard risk assessment maps of Cuqin County and Gaize County are formed.The geological hazard extraction method and geological hazard risk evaluation method used in this paper have certain reference value for geological hazard research and prediction..