藏东南天摩沟高位链式灾害发育特征及动力学过程研究OA

High-altitude geohazard chains are widely distributed along the southeastern margin of the Qinghai-Xizang Plateau in China,posing severe threats to downstream towns and major engineering facilities.Taking Tianmo gully in southeastern Xizang as an example,disaster types,distribution patterns,formation mecha-nisms,and characteristics of propagation and deposition are analyzed through remote sensing imagery,InSAR,and numerical simulations.Results indicate that the study area is predominantly affected by rock-ice avalanches,collapses,and rock slides,with maximum surface deformation reaching 11 m.The gully contains abundant loose deposits that provide material sources for disaster chain amplification.Short-term heavy rainfall and rising tem-peratures jointly accelerate glacier melting,thereby triggering high-altitude ice-rock mass sliding.Numerical sim-ulations reveal that the extreme elevation difference enables rock-ice avalanche masses to reach maximum veloci-ties of 100 m/s during free fall.The resulting debris flows propagate through gullies at speeds exceeding 20 m/s,reaching downstream areas within minutes.Their tremendous erosion capacity further amplifies disaster volume,with maximum erosion depths reaching 2.5 m.