青海省格拉沟形成演化机制及其主要工程地质问题

格拉沟位于青海省内陆滩地，其形成演化反映了西北地区典型的水土流失过程。文章在收集大量野外资料的基础上，研究了格拉沟的形成演化机制，并对该沟道主要工程地质问题进行了探讨。分析认为，格拉沟形成演化是该地区特殊的内因外因共同作用的结果，基于此对其发育演化阶段进行了划分与预测。该沟主要工程地质问题为边坡稳定性、渗透稳定性、河流侵蚀等。其中边坡稳定性主要包括天然岸坡整体稳定性及崩塌、坠溜、滑塌等；渗透稳定性主要包括潜蚀与管涌；河流下切与溯源侵蚀则成为岸坡失稳破坏的重要诱发因素。探讨格拉沟形成演化机制及其主要工程地质问题，对于研究西北地区水土流失机理及其产生的环境问题具有一定的借鉴作用。

Formation & evolution mechanism and its main engineering geological problems of Gelagou Gully, Qinghai Province

Gelagou gully is developed in a river floodplain of some inland in Northwest China.The formation & evolution process of the gully belongs to the typical soil erosion which is one of the main environmental geological hazards in Northwest China.The paper researches on the formation &evolution mechanism of the gully,and discusses its main engineering geological problems according to abundant field data.The paper considers that the formation and evolution of gully is the concurrent result of endogenic and exogenic factors in Gelagou region.On the basis of this analysis,several stages of the gully's formation & evolution are compartmentalized and predicted.The main engineering geological problems of the gully are slope stability,seepage stability and fluvial erosion,etc.Slope stability consists of natural slope monolithic stability and the main slope failure modes such as collapse,falling and landslide.Seepage stability consists of suffosion and piping.Stream trenching and headward erosion are the very important inducement for slope failure.Discussing the formation & evolution mechanism of the gully and its main engineering geological problems has the use for reference to researching mechanism and environmental issues of soil erosion in Northwest China.