北京山区泥石流的分类与类型

采用科学性、实用性和简明易行性的泥石流分类原则，制定出北京山区泥石流的分类指标，从7个方面对已判定出的705条泥石流进行分类。结果如下：1．按泥石流发育的地貌形态分类，有河谷型泥石流57条，沟谷型534条，山坡型114条(处)；2．按泥石流的暴发规模分类，有大规模泥石流51条，中等规模164条，小规模490条(处)；3．按泥石流的流体性质分类，有粘性泥石流136条，稀性泥石流30条，过渡性泥石流539条；4．按泥石流的发育阶段分类，有发展期泥石流296条，活跃期343条，衰退期66条；5．按泥石流的危害程度分类，有危害严重的泥石流117条，较严重的255条，中等的161条，轻微的172条；6．按泥石流的活动频率分类，有中频率的泥石流539条，低频率的166条；7．按泥石流形成与人类活动的关系分类，有人为泥石流36条，自然泥石流669条。

Classification of Debris Flow in the Mountains of Beijing

According to practical and easy criterions about characteristics, classification of debris flows in Beijing mountains has been established, which will play a vital role underlying the prevention and control of debris flow disasters. Debris-flow sites including gullies and slopes found in mountains of Beijing are 705, which can be divided into the following seven criterions: 1. Classification by geomorphology , there are 57 river-type debris flows,534 gully-type debris flows, 114 slope-type debris flows; 2. Classification by the scale of occurrence, there are 51 large-scale debris flows,490 middle-scale debris flows and 164 small-scale debris flows. 3. classification by properties of the fluid, there are 30 viscous debris flows, 539 sub-viscous debris flows and 136 intermediate debris flows. 4. Classification by the evolution, there are 296 debris flows of developing stage, 343 of active, 66 of decline. 5. Classification by harm to human, there are 117 debris flows of the most serious danger, 225 of, the second serious, 161 of medium and 172 of slight 6. Classification by frequency, there are 166 debris flows with moderate frequency and 539 with low frequency. 7. Classification by the relation between formation and human activities, there are 36 man-made debris flows and 669 nature debris flows.