安宁河流域典型沟谷泥石流危险性评价

冕宁县安宁河流域为地质灾害密集分布区，安宁河断裂穿越于此，构造复杂，冷渍沟在上游左岸发育。在强降雨条件下，该沟就会暴发泥石流，堵塞安宁河流域和掩埋杀叶马村房屋和道路。冷渍沟泥石流具有流域面积小，主沟长度短，沟床纵比降大等特征，为了研究安宁河流域内泥石流的危险性，以冷渍沟为例，分析不同降雨周期下的泥石流暴发强度，模拟泥石流的运动过程并进行危险性评价。模拟的最大流速、最大堆积深度和降雨强度三者结合建立冷渍沟泥石流危险性评价模型。研究结果表明，冷渍沟泥石流危险范围内高危险区域占27%，主要集中在松散固体物质较多的沟道，中危险性区域和低危险区域各占56%和17%，该结论为危险范围内的居民和重点设施的风险管控提供参考。

Hazard assessment of typical gully debris flow in Anning river:A case study at the Lengzi gully

The Anning river basin is a densely distributed area of geological hazards, where the Anning river rift crosses, with complex tectonics and the Lengzi gully developing in the upper left bank. The gully is subject to mudslides under heavy rainfall conditions, blocking the Anning river basin and burying houses and roads in the village of Yema. Lengzi gully debris flow has the characteristics of small area,a short main trench and a large channel longitudinal slope. To explore these damage, taking Lengzi gully as an example, the intensity of debris flow burst under different rainfall cycles is analyzed, and the movement process of debris flow is simulated and the risk assessment is carried out. Combined with the simulated maximum flow velocity, maximum accumulation depth and rainfall intensity,the hazard assessment model is established.The results show that in the danger range of Lengzi gully debris flow, the high risk area accounts for 27%, mainly distributed in the channel with more loose solid materials, and the medium risk area and low risk area account for 56% and 17%, respectively. this conclusion provides a scientific basis for the monitoring and early warning of key facilities in the danger range.