四川省北川县赵家沟地震次生泥石流形成条件分析  

Analysis on the developing conditions of debris flow induced by Wenchuan earthquake in Zhaojia Gully of Beichuan County,Sichuan Province

作　　者：朱忠礼[1] 刘希林[2,3] 尚志海[2] 

机构地区：[1]遥感科学国家重点实验室北京师范大学地理学与遥感科学学院,北京100875 [2]中山大学地理科学与规划学院,广东广州510275 [3]中山大学自然灾害研究中心,广东广州510275

出　　处：《中国地质灾害与防治学报》2010年第4期57-62,共6页The Chinese Journal of Geological Hazard and Control

基　　金：国家科技支撑计划项目(2008BAK49B04)

摘　　要：赵家沟位于北川县擂鼓镇坪上村西北侧,属汶川地震极重灾区,在地震发生前为一般性清水沟或洪水沟。由于地震的影响,流域内发育了多处滑坡和崩塌,斜坡上和沟道中堆积了大量松散固体物质。在2008年9月24日暴雨的作用下,赵家沟流域发生了百年不遇的泥石流灾害,成为地震次生泥石流沟。通过现场实地调查和室内分析,对地震次生泥石流灾害形成的地质地貌条件、物源条件和水源条件进行了分析。表明地震次生泥石流灾害的发生频率和规模有可能加大,其危险性由于松散固体物质的增大而上升,这是地震次生泥石流灾害显著的特征。Zhaojia gully is located at northwest side of Pingshang village of Leigu town,Beichuan county,Sichuan,China,which was heavily hit by Wenchuan Earthquake.It was general water ditch or flood channel before the earthquake,and developed many landslides and collapses with loose solid material deposited on the slopes and the channel after the earthquake.Driven by the heavy storm on September 24,2008,rare debris flow happened in Zhaojia gully,which made it into a post-earthquake debris flow gully.By on-site field survey and laboratory analysis,this paper studied the developing conditions of debris flow,including geological and geomorphologic conditions,sediments source conditions,and rainfall conditions.The analysis shows that because of earthquake induced solid material,the frequency and magnitude of the debris flow and its hazard will increase greatly,which is the most significant feature of post-earthquake debris flow.

关 键 词：泥石流 形成条件 地震次生灾害 四川省北川县 赵家沟 

分 类 号：P642.23[天文地球—工程地质学]