碱坪沟地震次生泥石流形成特征与发展趋势  

Characteristics and Trend of Earthquake-induced Debris Flow Initiation in Jianping Gully

作　　者：杨成林[1,2] 陈宁生[1] 邓明枫[1,2] 邓虎[3] 佘涛[4] 

机构地区：[1]中国科学院水利部成都山地灾害与环境研究所山地灾害与地表过程重点实验室,四川成都610041 [2]中国科学院研究生院,北京100049 [3]成都理工大学地球科学学院,四川成都610059 [4]中国地质科学院探矿工艺研究所,四川成都611734

出　　处：《水土保持通报》2011年第6期59-63,共5页Bulletin of Soil and Water Conservation

基　　金：水利部科技推广计划项目"山洪灾害监测预警实用系统"(TG1069);中国科学院成都分院-都江堰院地合作项目"都江堰市龙溪-虹口景区泥石流监测预警指标研究与示范"

摘　　要："5.12"汶川地震后,龙溪河碱坪沟流域内堆积了大量的松散固体物质,成为参与泥石流形成的主要物源。碱坪沟于2009—2010年先后3次暴发大规模泥石流灾害。通过对碱坪沟的地形、水源和物源条件的分析发现,该流域地形和水源条件满足泥石流形成的条件,且在地震前后未发生显著变化,而物源条件已经成为影响该区域泥石流形成与发展的主要因素。基于流域物源量与物源固结效应的研究结果表明,在5a内碱坪沟泥石流灾害较活跃,可能暴发大规模泥石流灾害。5～10a后,在降雨条件不发生较大变化以及不暴发大地震的情况下,流域内泥石流规模和频率会逐渐减小,只有在低频率暴雨作用下才可能暴发大规模泥石流灾害。After the ＂5·12＂ Wenchuan Earthquake,plenty of loose soil materials accumulated in Jianping Basin of Longxi River,which is the main source material for debris flows initiation.Three large-scale debris flows occurred in Jianping Gully in 2009 and 2010.In contrast with the pro-earthquake conditions,the terrain and rainfall have not changed a lot and are appropriate for the initiation of debris flow,so loose materials can be regarded as the most significant impact factor for the debris flow characteristics and its development trend.The results based on the analysis of loose materials and its consolidation impact shows that debris flows in Jianping Gully will occur frequently in 5 years.The possibility of catastrophic debris flow will be high.In the next 5~10 years,the frequency and scale of debris flows in Jianping Gully will decline if there is no significant change for the rainfall and no strong earthquake,while large-scale debris flows can also occur under extremely rainfall with low frequency.

关 键 词：碱坪沟 泥石流 形成条件 趋势 

分 类 号：P642.23[天文地球—工程地质学]