Geological Hazard Risk Assessment On Ili Valley Based On RS And GIS

Geological disaster risk assessment method is the important subject in the research fieldof the current geological disasters； is an important issue of analyzing the relationship ofgeological disasters and human social economic activities， quantitative evaluation focusingon destructive effect of geological disasters；provides a basis for risk management andprevention of geological disasters.Ili Valley is the susceptible area and the hardest-hit area of geological disasters inXinjiang Province. This study is based on the detailed investigation project of geologicaldisasters in Ili Valley of Xinjiang Province， and the domestic and foreign researchachievements and methods concerning the geological hazard risk evaluation. The geologicalenvironmental conditions of Ili Valley were collected and analyzed. It is taken to analyze thegrowth characteristics and distribution law by the remote sensing investigation of the fieldgeological hazards. Hence, the RS and GIS is used to explore the geological disaster riskassessment methods. The risk assessment of landslide hazard in the Nilka County is used toverify the established geological disaster risk assessment method.This study obtains the following results：1. Risk assessment is consisit of two aspects that includesashazard assessment andvulnerability assessment， disaster prevention and mitigation capabilities is use to thevulnerability assessment.2.In hazard assessment，Slope，aspect，slope height，geomorphic process，geotechnical liquidproperty，rock mass structure，gully density，rainfall，geological structure，earthquakeintensity，the types of groundwater，vegetation biomass，land use types，mining activities，construction activities，the density of hazards16indexes were chosen as the indicators ofhazard assessment according to the actual situation of the study area，and informationextraction function of RS and spatial analysis statistical functions of GIS were used to buildevaluation unit to extract and quantize hazard indicators. Artificial neural network model wasselected for hazard assessment，and hazard partition was completed according to hazard index.The study area was divided into high-hazardous areas， medium-hazardous areas andlow-hazardous areas according to the hazard index.3. Buildings， roads， farming and animal husbandry output value， mineral resources， population density，population age structure，population by education degree，grassland，cultivated land，forest land，surface water，the vegetation coverage，Hazard prevention andmitigation capacity13indexes were selected as index system of vulnerability assessmentfrom the four aspects of material，economic，society and environment. Hazard prevention andmitigation capacity was quantized by the level of monitoring，control group of measuringability and management coordination and scene command ability，local government financialresources，social security，the public’s awareness of hazard prevention，per capita insuranceconsciousness，the medical institution beds per one thousand people，per one thousand peoplehealth technical personnel and was considered into vulnerability assessment.Taking eachvillages and towns of Nilka County as evaluation unit to discuss and use Data EnvelopmentAnalysis (DEA)，completing the vulnerability assessment of geological hazards in the studyarea partition，dividing the study area into medium-vulnerability areas，low-vulnerability areasand no-vulnerability areas based on the existing research.4、Based on hazard assessment and the vulnerability assessment，the risk index of evaluationcan be expressed by multiplying dangerous index with vulnerable index.according to theevaluation formula of risk assessment to calculate the geological hazard risk index of all theevaluation units，and completing the geological hazards risk zoning in the study area，dividingthe study area into high-risk areas，medium-risk areas，low-risk areas.The research utilized the information extraction by RS and the spatial analysis and drawfunction by GIS on the geological hazard risk assessment of Ili Valley and the assessmentresult is objective and reliable. It shows that this method has good application value.