【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。更多还原

【Abstract】 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.更多还原