| Jiuzhaigou county is located in the transitional zone between Sichuan basin and Qinghai-tibet plateau.Tectonic activities are active with high valleys,deep mountains,ravines and vertical all over there.Triassic sandstone and SLATE strata are widely distributed in the region,followed by Permian,carboniferous and devonian strata.Affected by natural geographical environment and human engineering activities,the geological disasters in jiuzhaigou valley are serious.Especially affected by the "8.8" earthquake in 2017,271 secondary geological disasters occurred,which caused a large amount of property losses and seriously damaged the ecological environment.This paper is taking Jiuzhaigou county geological disaster and repair as the research object,based on the principle of same attention to the protections and restorations of Jiuzhaigou county,this paper summarize geological disasters in jiuzhaigou county systematically by a field research and analysis of the relevant technical means.this paper collected the elements of geological hazards on jiuzhaigou county,then summarize a set of strategies about the geological disaster factors and repairs for Jiuzhaigou county.Firstly,based on the characteristics and distribution of geological hazards in jiuzhaigou county,this paper analyzes the factors of geological hazards from five aspects: geological landform,stratigraphic lithology,hydrological conditions,earthquake and human activities.Among many conditions and inducing factors of geological hazards of jiuzhaigou county,The risk assessment system was established by 9 evaluation factors,such as vegetation cover degree,seismic intensity,annual average precipitation,distance from river and distance from road,so that the index weight was calculated by principal component analysis method by using the method of information quantity to calculate and assign the amount of information to the index.Then,on the basis of index weight,the risk zoning map is obtained by using the spatial weighted superposition function and reclassification of ArcGIS software,,and the hazard assessment of geological disasters in jiuzhaigou county was completed,which is used to guide the disaster prevention and reduction work of geological disasters in jiuzhaigou county.Finally,through the analysis of geological disaster damage to the ecological environment influence,combined with the risk assessment results of jiuzhaigoucounty,the landslide mainly adopts guest soil spraying planting method and lattice protection method,the collapse point adopts galvanized barbed wire guest soil spraying planting method,and the debris flow adopts the concrete ecological restoration measures and treatment of geological hazards,such as construction of blocking dam,drainage groove and other engineering protection combined with land reclamation. |
