Dynamic Characteristics of the Long Runout Rock-ice Avalanche at High Altitude——A Case from the Zelongnong Basin,Eastern Himalayan Syntaxis,China  

作　　者：GAO Shaohua YIN Yueping LI Bin GAO Yang ZHANG Nan ZHANG Tiantian GAO Haoyuan LIU Xiaojie 

机构地区：[1]Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China [2]China Institute of Geological Environment Monitoring,Beijing 100081,China [3]Key Laboratory of Active Tectonics and Geological Safety,Ministry of Natural Resources,Beijing 100081,China [4]School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China

出　　处：《Acta Geologica Sinica(English Edition)》2024年第5期1376-1393,共18页地质学报（英文版）

基　　金：granted by the National Natural Science Foundation of China(Grant Nos.U2244227 and U2244226);the National Key R&D Program of China(Grant No.2022YFC3004301);China Geological Survey Project(Grant No.DD20230538)。

摘　　要：Rock-ice avalanches have frequently occurred in the Eastern Himalayan Syntaxis region due to climate change and active tectonic movements.These events commonly trigger catastrophic geohazard chains,including debris flows,river blockages,and floods.This study focuses on the Zelongnong Basin,analyzing the geomorphic and dynamic characteristics of high-altitude disasters.The basin exhibits typical vertical zonation,with disaster sources initiating at elevations exceeding 4000 m and runout distances reaching up to 10 km.The disaster chain movement involves complex dynamic effects,including impact disintegration,soil-rock mixture arching,dynamic erosion,and debris deposition,enhancing understanding of the flow behavior and dynamic characteristics of rock-ice avalanches.The presence of ice significantly increases mobility due to lubrication and frictional melting.In the disaster event of September 10,2020,the maximum flow velocity and thickness reached 40 m/s and 43 m,respectively.Furthermore,continuous deformation of the Zelongnong glacier moraine was observed,with maximum cumulative deformations of 44.68 m in the distance direction and 25.96 m in the azimuth direction from March 25,2022,to August 25,2022.In the future,the risk of rock-ice avalanches in the Eastern Himalayan Syntaxis region will remain extremely high,necessitating a focus on early warning and risk mitigation strategies for such basin disasters.

关 键 词：rock-ice avalanche dynamic characteristics mobility MORAINE Eastern Himalayan Syntaxis 

分 类 号：P642.2[天文地球—工程地质学] P426.636[天文地球—地质矿产勘探]