金沙江白格两次滑坡几何形态分析与体积计算

2018年10月10日和11月3日，西藏昌都市江达县波罗乡白格村先后两次发生大规模滑坡并堵塞金沙江，引起社会广泛关注。滑坡的几何形态和体积是滑坡机理研究和滑坡防灾减灾的关键问题和重要基础。为此，本文基于无人机拍摄获取的数字正摄影像（DOM）和DEM、滑坡前的地球电子地形数据（ASTER GDEM）30 m分辨率DEM、分辨率为3 m的Planet卫星影像，以滑坡后的等高线为基准，参考滑坡前的微地貌特征，重绘滑坡前的地形；然后以滑坡前后地形为基础，在ArcGIS软件上进行体积计算，结合AutoCAD绘制滑坡剖面，分析滑坡深部厚度特征。研究表明采用这种方法可以获取滑坡的体积和几何形态特征，可为类似滑坡灾害研究提供参考。

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.