Abstract:

Yangyun town is a place where debris flow frequently happens in Gaizhou city and suffers from economic loss. This paper, based on the debris flow happened in July, 1981, studies the debris flow accumulation, terrain and vegetation, analyzes the features and conditions of debris flow. This study indicates that this debris flow is derived from flooding, large, accumulating coarse gravels, poor sorting and roundness. Materials are from the nearby mountain, weathered granite. Debris flow most occurs in the rainstorm seasons in July to August, follows along steep and deep valleys and accumulates in the valley mouth. The rainstorm is an evocator for this debris flow.

Key words: debris flow, terrain, sediment, mountainous disaster, Gaizhou

摘要：

杨运乡是盖州市一个泥石流多发区，曾发生过多次泥石流，给当地造成了严重的经济损失。本文以1981年7月在该区发生的泥石流为研究对象，通过野外调查，对该区的泥石流堆积物、地形地貌、植被发育状况等方面进行了观察和测量，并收集了当地的地质资料和气候资料，分析了研究区泥石流的发育特征和形成条件。研究表明，本次泥石流为稀性、暴雨型泥石流，属于大型泥石流；堆积物为粗大砾石，无分选，磨圆差，物质主要来源于周围山体，是植被覆盖较低的花岗岩风化产物；泥石流主要形成于每年7—8月的暴雨季节，沿切割深、坡陡的冲沟发育，并在冲沟口形成堆积区；特大暴雨是本次泥石流发生的诱发条件。

关键词: 泥石流, 地貌, 沉积, 山地灾害, 盖州