鄂西清江流域滑坡崩塌致灾背景及成灾模式

摘要

The mountain area in western Hubei Province,mainly in Qingjing river basin,is one of landslide and avalanche prone regions in China.Based on the results of the geological disaster investigation in 1 1 counties of this area,including 2,276 landslides and 567 avalanches,the characteristics of development and distribution of these landslides and avalanches are summarized in this paper by the method of statistics,induction and analo-gy.At the same time the control effect of different hazard-cause factors was respectively analyzed,including geological structures,lithology combination,river evolution,human activities and rainfalls.According to the key controlling factor,the formation patterns of landslides can be sorted into 4 types of regular ones,i.e.rain-fall controlled type,box-shape (close-narrow shape)anticline controlled type,wide and gentle shape syncline controlled type,and reservoir water-level controlled type,and those of avalanches can be classified into 2 types of regular ones,i.e.wide and gentle shape syncline controlled type,and karst-pillar controlled type.At last it was inferred that the risk of 3 types of landslides and avalanches must be focused on and prevented in the study area.%鄂西清江流域是我国滑坡崩塌地质灾害易发区。在该区域11个县市地质灾害详细调查成果基础上，运用归纳和类比等方法，对区内2276个滑坡和567个崩塌（危岩）的要素数据进行统计分析；归纳总结了区域滑坡崩塌的基本发育特征和分布规律，并从构造作用、岩性组合、河流地貌演化、人类活动、降雨等几个方面，分析多种致灾背景对滑坡崩塌的不同影响和控制作用；继而根据主控因素归纳分析了区内滑坡具有的降雨型、箱形（紧窄）背斜型、宽缓向斜型和水库型等4类主要成灾模式，以及崩塌（危岩）具有的宽缓向斜型和岩溶石柱型两类主要成灾模式；指出了今后需要重点防控的三种类型滑坡崩塌风险。