甘肃陇南武都区泥石流易发性评价

文章分析了甘肃陇南市武都区泥石流形成的自然环境背景、发育特征及易发性。通过野外实地考察,查明了泥石流的发育情况,在此基础上,采用模糊物元可拓方法对泥石流的易发性进行了评价。分析表明,研究区的泥石流具有分布密度高、冲沟及坡面泥石流成片发育、北岸泥石流较南岸发育且粘性泥石流所占比例大于南岸的发育特征;选取岩性、沟床比降、山坡坡度、完整系数、发育程度、降水、断层密度7个因子构建泥石流易发性评价指标体系。通过易发性评价,研究区104条泥石流沟中,66条为高易发性,占总数的63.5%;32条为中等易发性,占总数的30.8%;6条为低易发性,占总数的5.7%。

Susceptibility evaluation of debris flow in the Wudu District,Longnan City, Gansu Province

The natural environment backgrounds,development characteristics and susceptibility of debris flows in the Wudu District of Longnan City are discussed in this paper.The development characteristics of debris flows in this area are analyzed through field investigation;and the susceptibility of debris flows in the study area is discussed by means of fuzzy matter element extension method.The result shows that the characteristics of debris flows in the study area are as follows： the distribution density is high;the small gully and slope debris flows develop widely;the debris flows on the north bank are more developed than those of on south bank,and the proportion of viscous debris flows on the north bank are more than those of on the south bank.The 7 factors including lithology,channel gradient,slope,integrity coefficient,development degree,precipitation and fault density,are selected to form a susceptibility evaluation index system.According to the evaluation,among the 104 debris flow gullies,there are 66 high-susceptible debris flow gul-lies which account for 63.5%;32 middle-susceptible debris flow gullies which account for 30.8%;6 low-susceptible debris flow gullies which account for 5.7%.