磨西河流域冰碛补给一暴雨型泥石流形成机制研究

Formation Mechanism of Moraine Supplied—Rainstorm Debris Flow in Moxi Basin

冰碛补给—暴雨型泥石流是发育在高海拔冰缘山区的一种特殊灾害地貌过程,隐蔽性较强,故对这一灾害的认识尚不够全面和深入。基于此,本研究在总结目前泥石流形成机理研究进展的基础上,以发育有大量冰碛补给—暴雨型泥石流的贡嘎山东坡磨西河流域为例,通过实地调查,对冰碛补给—暴雨型泥石流的形成条件及形成过程机制进行了探讨,提出了这类泥石流形成过程的4阶段模式:清水汇流阶段→单颗粒固体物质起动阶段→掏蚀和侧蚀阶段→泥石流形阶段。最后,对冰碛补给—暴雨型泥石流亟待深入研究的问题进行了分析和总结。

Moraine supplied-rainstorm debris flow is a unique geographical process that often can be seen in high elevation glacial margin area,the potential harm from the debris flow has not be recognized enough because of it＇s invisibility,and only a few researchers pay attention to it.Based on the debris flow mechanism progress and the field survey,this article took Moxi Basin as an example,where distributed many moraine supplied-rainstorm debris flow,and analyzed the forming factors and process,and presented the 4 steps of this debris flow process： branch water converging step→individual particle material starting up step→under-erosion and lateral erosion step→debris flow initiation step.Finally,this article summarized related problems about the mechanism of moraine supplied—rainstorm debris flow which need to be further studied.