Research On Landslide Geological Disasters Based On Remote Sensing

The Heqing area is located in the east of the Yunling Mountains and the southern end of the Hengduan Mountains in western Yunnan,which is an activity area by the Cenozoic Himalayas Movement.It has diverse and complex of climate types,poor geological environment and landslides.A number of data materials indicate that the landslide geological disaster has become one of the important factors hindering the social and economic development of Heqing area.This research is supported by project "Ecological Geological Survey of Northwest Yunnan".Based on the "Landsat-8" remote sensing image,GIS and RS software platform,three evaluation methods including logistic regression model,information quantity model and analytic hierarchy process are used to evaluate and grade the susceptibility of landslide geological hazards in Heqing area,and the following results have been achieved:(1)Based on the Arcgis software platform,remote sensing interpretation marks is established by Landsat-8 remote sensing images as the base map for interpretation,178 landslides Geological disaster point is obtained by performing human-machine interactive interpretation of landslide geological disasters in Heqing area.(2)The relationship between the 9 evaluation factors selected in this paper and the occurrence of landslide:The relative density value of landslide reached the peak in the range of 1500-1800 meters,the slope reaches the peak in the range of 33-42 °,and the road distance of 0-200 meters is the most densely distributed area of landslides,These are mainly disturbed by human engineering activities such as mines,road construction and building houses,and the slope body is unstable,which greatly increases the probability of landslides occurrence;the relative density values of the slope direction of 90-135 ° and 270-360 ° are the largest,due to the subtropical monsoon climate As a result,rainfall on the windward slope is more than that on the leeward slope,which leads to instability of the slope body;the relative density values of the four types of landslides,which are harder rock with softer rock,harder rock with soft rock,hard rock with soft rock and soft rock,There are 171 landslides distributed;the relative density value of the area 0-1000 m from the fault is higher than other areas,indicating that the closer to the fault,the easier the landslide occurs;the effective free surface of the slope increases when the river is 100-200 meters away from the river Landslides are more likely to occur within the scope;rainfall has less impact on landslides than other factors,but it cannot be said that there is no impact;landslides are more likely to occur in areas with low vegetation coverage.(3)Based on the analysis of landslide disaster factors in Heqing area,the influence degree of elevation,slope,slope direction,lithology,fault,road,water system,precipitation and NDVI on the occurrence of landslide is obtained;Each architecture model is established by three methods of Logistic regression model,information quantity model and analytic hierarchy process and the weight of 9 evaluation factors is calculated in each model.With the help of relevant statistical software,the prediction accuracy of each model is obtained,the accuracy of each model is tested by the ROC curve test method,and the prediction accuracy of the Logistic regression model,information model and AHP is 90.2%,79.2% and 82.6%,respectively.Therefore,the prediction of the Logistic regression model Ability is higher than AHP than information model.(4)By using the cross test method to test the results of landslide prone zoning,the strength value of landslide prone increases from low prone,medium prone and high prone,which shows that the results of prone zoning are reasonable.Based on Arcgis,the susceptibility assessment and grading of landslide geological disasters are divided into high prone area accounting for 21.5%,high-prone area accounting for 44.7%,and low-prone area accounting for 33.8%.