| Qingchuan County is located in the Sichuan,Gansu and Shaanxi at the junction of the terrain northwest of the high-low.As the geological environment in Qingchuan County is very complicated,it's one of the most serious areas in China suffered from geological hazards.This question has been seriously restricted social and economic development in Qingchuan.With the help of project work “the geological hazards detailed investigation in Qingchuan County.On the foundation of extensively collecting the relevant geology data and investigation data in the region,we expatiate the natural geography and the background conditions of geological environment.This article describes the main types of geological hazards in Qingchuan County.Then the basic characteristics,the distri-bution rule,the formation mechanism and controlling factors of the geological hazards are explored in detail.Based on the analysis of influence factors,the slope?relative height?stratum lithology?the distance of fault?road transportation and river system and rainfall are selected as evaluation factors.Based on the Arc GIS platform,we extracting the rele-vant layer,Established the evaluation model of information,to achieve the Evaluate susceptibility and regional planning of landslide hazards in Qingchuan County.At the same time the typical landslides in the evaluation results are verified,the landslide disaster prevention and control countermeasures are put forward.Has achieved the following results:1?A detailed analysis of the study area in natural geographical environment and regional geological environment condition,on the basis of the characteristics of the development of landslide disaster in the study area,analyze the formation mechanism and influencing factors.Main research area of landslide disaster for quantity,wide distribution,and administrative area in time and space distribution is not uniform,but the distribution is concentrated on the location.2?To analyze the distribution features of the landslide disaster in the study area,on the topography and geomorphology,landslides are mainly distributed in low mountain landscape area,the area of change is big,strong cutting,and for human settlements,easy to induce landslide disaster.In time,landslide occurs mainly in June to August,the rainy season is prone on landslide disaster.3?In the study area based on the analysis of the influence factors of landslide disaster,to build the slope,relative elevation difference,the formation lithology,respectively from the distance of the fault,roads,drainage and the average annual rainfall of seven factors such as the evaluation index system,using GIS software,the information model is used for landslide hazards in evaluation.The results show that:The extremely high-risk covers an area of 688.72 square kilometers,accounting for 21.41% of the county area.The medium-risk covers an area of 1455.24 square kilometers,accounting for 45.25% of the county area.The low-risk and extremely low-risk covers an area of 1072.27 square kilometers,accounting for 33.34% of the county area.The Evaluation results correspond to the actual condition very well.4 ? The typical landslide points were selected and analyzed through field investigation and laboratory tests.Then the stability characteristics of landslide,slide bed,sliding surface and landslide were analyzed,and the transfer coefficient method was used to evaluate the stability.It is concluded that the typical landslide is in a steady state in nature.Under the heavy rainfall condition,the whole landslide is basically stable,the safety reserve is low,and it is easy to be deformed again under heavy rainfall or continuous rainfall.5?Based on the results of the landslide hazard zonal partitioning and the stability analysis of typical disaster points,the paper puts forward some countermeasures such as group and group prevention,relocation and project management. |
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