关门沟位于陕西省宝鸡市凤县坪坎镇，地处秦岭南麓，区内山高沟深、地形陡峻，局部地下赋存有铅锌矿资源，历史上就曾发生过泥石流。但自沟内铅锌矿开采后，因大量矿渣堆弃沟道，于2013年7月再次发生泥石流，该泥石流因大量弃渣汇入，物源充足、破坏力大，具有矿山泥石流的特征，冲毁沿沟矿山用房和工业场地，严重威胁沟口居民的生命财产安全。本文以凤县关门沟泥石流为研究对象，对该泥石流的基本特征和运动过程进行了研究，期望对矿山泥石流的预测、预警以及减灾防灾提供科学依据。 通过对关门沟流域地质环境条件与降雨特征综合分析，认为关门沟泥石流为中型中频、稀性、暴雨类、沟谷泥石流，短时间强降雨和采矿活动堆弃在沟道的废渣是泥石流形成的主要诱发因素。根据影响关门沟泥石流形成主要因素与泥石流形成、发展、运动之间的关系，对泥石流形成机理进行分析，认为关门沟泥石流少年期、青年期以重力侵蚀作用为主，水力侵蚀作用为辅；壮年期、老年期以水力侵蚀作用为主，重力侵蚀作用为辅。采取定性分析和定量评价相结合的方法，对泥石流易发性做出评价，得出关门沟泥石流易发程度等级为中等易发性。在对泥石流工程地质特征分析基础上，基于PFC-2D模拟软件，构建了关门沟泥石流颗粒流模型，对泥石流运动过程进行了深入研究，认为关门沟泥石流运动过程可以分为两个阶段：第一阶段为汇流聚能阶段，第二阶段为泄流冲淤阶段；通过数值模拟结果，对泥石流致灾后果进行分析，沟道堆积体的实际最大冲淤距离可达780.34m，冲淤厚度沟口处可达11.99m，泥石流最远冲淤至银母寺河对岸，淹没沟口平硐，对沟口居民的生命财产安全带来巨大威胁；各监测点平均速度为4.39m/s，与理论计算得到的泥石流流速参数（4.54m/s）较接近。 论文相关研究方法及成果可以为同类泥石流基本特征、形成机理和动力学分析研究提供必要的借鉴。

The closure ditch is located in pingkan town, fengxian county, baoji city, shaanxi province. It is located at the southern foot of qinling mountains. The mountain is high and deep, the terrain is steep, and there are lead and zinc mineral resources underground. However, since the mining of lead and zinc mine in the gully, a large amount of slag was dumped into the gully, and the debris flow occurred again in July 2013. Due to the large amount of waste material, the debris flow has the characteristics of mine debris flow, which washed away the houses and industrial sites in the gully, seriously threatening the life and property safety of residents in the gully. This paper studies the debris flow in guomen gully, fengxian county, and studies the basic characteristics and movement process of the debris flow, hoping to provide scientific basis for the prediction, early warning and disaster reduction of mine debris flow. Based on the comprehensive analysis of geological environment conditions and rainfall characteristics in mengmengou basin, it is concluded that the debris flow in mengmengou basin is medium-frequency, sparse, rainstorm and gully debris flow. Based on the relationship between the main factors affecting the formation of debris flow and the formation, development and movement of debris flow, the mechanism of debris flow formation is analyzed. In the mature and old age, hydraulic erosion is the main and gravity erosion is the auxiliary. The method of qualitative analysis and quantitative evaluation is adopted to evaluate the susceptibility of debris flow. Based on the characteristics of landslide engineering geology analysis, based on PFC - 2 d simulation software, built close gully particle flow model, carried on the thorough research of debris flow movement process, think of closed gully movement process can be divided into two stages: the first stage for bus shaped stage, the second phase to discharge sediment phase; Based on the numerical simulation results, the disaster consequences of debris flow are analyzed. The maximum distance of debris flow and deposition is 780.34m, and the thickness of debris flow and deposition is 11.99m at the mouth of the ditch. The debris flow and deposition are as far as the other side of yinmu si river, flooding the mouth adit, which poses a great threat to the life and property of the residents in the mouth. The average velocity of each monitoring point is 4.39m/s, which is close to the flow velocity parameter (4.54m/s) obtained by theoretical calculation. Relevant research methods and results of this paper can provide necessary reference for the basic characteristics, formation mechanism and dynamics analysis of similar debris flows.