GEOMETRIC SHAPE ANALYSIS AND VOLUME CALCULATION OF THE TWO SUCCESSIVE BAIGE LANDSLIDES IN JINSHA RIVER

On October 10 and November 3, 2018, two successive large-scale landslides occurred in Baige Village, Polo Township, Jiangda County, Changdu City, Tibet, and blocked the Jinsha River, caused widespread social concern. Geometric shape and volume of landslides are key issues and important foundation for landslide mechanism research and prevention and mitigation of landslide disaster. To this end, these date include the digital orthophoto map(DOM) and digital elevation model(DEM)taken by UAV,pre-slide 30 m DEM from ASTER GDEM and the Planet images with 3 m resolution are collected. The pre-slide terrain contours are hand painted based on the after-slide terrain contours and pre-slide micro topography. Then, based on the topography before and after the landslides, volume calculation is carried out on the ArcGIS software. In addition, several cross sections are plotted with AutoCAD,based on which the depth characteristics are analyzed. The study shows that the volume and geometric features of landslide can be obtained by this method, which can provide references for similar landslide hazards research.