都江堰市龙池镇煤炭坪泥石流形成条件及特征

Formation conditions and characteristics of Meitanping gully debris flow in Longchi Town,Dujiangyan City

通过对都江堰市龙池镇煤炭坪泥石流灾害的现场调查,分析了泥石流的特征及形成条件,并对沟道内的松散固体物质储量进行了计算,分析了危险区范围。结果表明:煤炭坪流域的地形特征为泥石流的形成提供了有利的地形条件,"5·12"汶川地震和"4·20"芦山地震为泥石流的形成提供了丰富的物源条件,多次强降雨为泥石流的启动提供了充足的水源条件。通过计算得出,煤炭坪沟道内可转化为泥石流的松散固体物质储量约为14.65×104m3,其中形成区为6.01×104m3,流通区为8.64×104m3,泥石流最大危险范围为0.2422 km2。

The characteristics and formation conditions of Meitanping gully debris flow were analyzed by field investigation in Longchi Town,Dujiangyan City,Sichuan Province. The storage capacity of loosened solid matter and hazard zone range were calculated in Meitanping gully. The results show that the characteristics of terrain provide favorable terrain conditions,the '5. 12 'Wenchuan earthquake and the '4. 20 'Lushan earthquake provide rich source conditions,and many heavy rainfall events provide adequate water conditions for the formation of debris flow in Meitanping gully basin. Moreover,the calculations show that the storage capacity of loosened solid matter is about 14. 65 × 104m3 in Meitanping gully,there is about 6. 01 × 104m3 in formation area,8. 64 × 104m3 in flowing area,and the maximal hazard zone range of debris flow is 0. 2422 km2.