2010年8月13日四川省绵竹市清平乡着降暴雨导致走马岭沟暴发泥石流,主沟及支沟内的大量松散堆积物一起冲出,导致绵运河改道.为了探讨强震区泥石流灾害的形成原因及成灾机理,利用野外现场调查资料和航空图像解译成果对马岭泥石流的流域特征,特别是地震条件下的泥石流物源特征,进行了分析.结果表明走马岭特大泥石流受降雨影响显著,流速为7.19m/s,最大洪峰流量为866.35m3/s,一次泥石流过流总量为121.64×104 m3,显示了强震区泥石流暴发的特点,认为震后绵运河区域进入了泥石流的高发期,降雨是强震区诱发泥石流的主要动力因素,泥石流暴发主要受前期累积雨量和当次激发雨量共同作用.%On August 13, 2010, the rainstorms in Qingping town of Mianzhu City caused a catastrophic debris flow which resulted in a large amount of loose materials removing out the catchment. The debris flow deposits caused the Mianyuan River to change its original channel. In order to explore the formation and mechanism of the debris flow in seismic regions, based on field surveys and aerial image interpretation, this paper analyses the watershed characteristics, and especially the characteristics of sediment supply for the debris flow occurrence in the Zoumaling basin. The results show that the rainfall is a significant factor of the Zoumaling debris flow. The velocity is 7. 19 m/s, the maximum peak discharge is 866. 35 m3/s, and a mud-rock flow volume amounts to 121.64×104 m3. The debris flow in the Zoumaling basin typically shows that debris flow activities will be more frequent in a long period, that rainfall is the main dynamic factor of debris flows in seismic regions and that debris flow is mainly affected by the joint action of the cumulative rainfall and a rainfall at that time.
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