火地塘林区沟道泥石流调查分析

Investigation and Analysis on Mud-stone Flow of Gullies at Huoditang Forest Region

1993年8月5日火地塘林区由暴雨引发了严重的泥石流危害。65min内降雨80～119mm，最大雨强为2．3mm／min。在所调查的3个流域内，泥石流残留堆积物为9173～15800m3；据估算，泥石流流量为8．49～49．16m3／s；根据泥石流发生的主导原因、形成过程和堆积物结构，这次泥石流属于暴雨型、水力类“水石流”。该区具有发生泥石流的地质、地形条件，暴雨是这次泥石流发生的主导因素，采伐作业和林道修建对流域的扰动是泥石流发生的诱因之一。

Serious mud-stone flow caused by rainstorm occurred at Huoditang forest region on August 5, 1993. Precipitation within 65 minutes was 80~119mm, the maximum was as high as 2. 3mm/min. Investigation at three watersheds rdeealed that remains of the mud - stone flow were 9173~15800m3; the estimated discharge wat 8. 49 ~ 49. 16m3/s. Considering the domi-nant cause, development cause, development process and structure of the remains the mud -stone flow belonged to rainstorm type, hydraulic nwater-stone'. At the region there were geo-logical and topographical conditions responsible for mud -stone flow. Rainstorm was the domi-nant factor leading to the mud -stone flow and cutting operation and forest road building the in-ducing ones.