Activity and catastrophe mechanism of the rock glacier in the Wulian Gully,southeast Qinghai-Xizang Plateau
Against the backdrop of global climate warming,the activity of rock glaciers in the Qinghai-Xizang Plateau has been enhanced,leading to an increasing trend of disasters.By using methods such as remote sensing image analysis,field investigation,meteorological and runoff monitoring,characteristic data of the Wulian rock glacier in southeastern Qinghai-Xizang Plateau were obtained,and the triggering factors and processes of the for-mation of debris flows were analyzed.The findings indicate that the Wulian rock glacier's mean velocity ranged from 1～3 m·a-1 between 2010 and 2017,with the frontal velocity being substantially higher than that of the mid-dle and rear.This advancement and associated instability of the rock glacier front can be attributed to the channel transportation of loose material sources.Notably,the rock glacier transported approximately 5 600～9 000 m3 of loose material,which triggered debris flow events in 2013 and 2014.The generation of such flows requires not only abundant loose sources but also sufficient water to initiate.In this study,the maximum runoff occurred dur-ing May and June,primarily driven by the melting of ice and snow resulting from elevated temperatures.By ex-amining the two debris flow events,it was discovered that high temperature was the primary contributing factor,and the disaster mechanism involved the rapid melting of surface ice and snow due to elevated temperatures,causing the accumulation of meltwater in depressions on the rock glacier surface,resulting in a pond that,when discharged,caused loose material in front of the rock Glacier to form debris flow.As climate warming exacer-bates in the future,rock glacier activity is anticipated to increase.Additionally,under the influence of rapid warming or heavy rainfall,the scale and frequency of debris flows may increase.Therefore,it is imperative to mitigate the risk of rock glacier disaster formation through debris flow prevention measures.
rock glacierdebris flowQinghai-Xizang Plateauclimate change
NETL
NSTL
万方数据
