7月3日茂县棉簇沟特大泥石流成因和特征分析
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摘要
通过对2011年7月3日的茂县棉簇沟泥石流灾害的现场调查,从物源、地形和水源条件入手,分析了灾害特征与形成演化过程。强降雨是本次泥石流的诱发因素,沟道内复杂的地形地貌特征为泥石流提供了演化和规模放大条件:(1)泥石流导致堰塞湖溃决,为泥石流提供了近1×104m3的水源,增强了泥石流的水动力条件,增加了沿途冲刷量;(2)沟道内多处基岩卡口和跌水放大了本次泥石流的规模和速度;(3)沿途固体物质补给使泥石流容重逐步增大。此次泥石流造成沟道微地貌改变,今后泥石流暴发的可能性和频率将会大大增加,高频率、中小规模泥石流将是今后该沟泥石流活动的特征。
The formation and evolvement process of this debris flow was analyzed based on the field investigation on the material sources, rainfall, and topography conditions. The rainfall was the inducing factor; however, the topography in the gully was the main reason which causes this catastrophic debris flow: (1)the dammed lakes formed in the earthquake were broken which increased the water supply, strengthened the dynamic force, and aggravated the erosion quantity finally. (2) the narrow sections and the drops amplified the peak flow and velocity of the debris flow in the gully. (3) the solid material supplies the debris flow and enlarged the density along the gully. The possibility and frequency of debris flow will be much higher in heavy rainfalls in the future, but the scale will be less than this giant debris flow because of the microtopography had been changing. Suggestions were proposed:the warning system, control engineering should be built and disaster prevention and reduction awareness of local people also should be improved.
The formation and evolvement process of this debris flow was analyzed based on the field investigation on the material sources, rainfall, and topography conditions. The rainfall was the inducing factor; however, the topography in the gully was the main reason which causes this catastrophic debris flow: (1)the dammed lakes formed in the earthquake were broken which increased the water supply, strengthened the dynamic force, and aggravated the erosion quantity finally. (2) the narrow sections and the drops amplified the peak flow and velocity of the debris flow in the gully. (3) the solid material supplies the debris flow and enlarged the density along the gully. The possibility and frequency of debris flow will be much higher in heavy rainfalls in the future, but the scale will be less than this giant debris flow because of the microtopography had been changing. Suggestions were proposed:the warning system, control engineering should be built and disaster prevention and reduction awareness of local people also should be improved.
引文
[ 1 ] Cui P,Chen X,Zhu Y,et al.The Wenchuan Earthquake ( May 12 2008 ),Sichuan Province,China,and Result ing Geohazards [ J ].Nat Hazards,2009,56 ( 1 ): 19-36.
[ 2 ]崔鹏,韦方强,何思明,等.5·12汶川地震诱发的山地灾害及减灾措施[ J ].山地学报,2008,26 ( 3 ): 280-282.
[ 3 ]谢洪,钟敦伦,矫震,等.2008年汶川地震重灾区的泥石流[ J ].山地学报,2009,27 ( 4 ): 501-509.
[ 4 ]崔鹏,韩永顺,陈晓清.汶川地震堰塞湖分布规律与风险评估[ J ].四川大学(工程科学版),2009,41 ( 3 ): 35-42.
[ 5 ]庄建琦.汶川震后孕灾环境下泥石流形成机理试验研究[ D ].成都:中国科学院成都山地灾害与环境研究所,2011.
[ 6 ]向灵芝,崔鹏,方华.震后灾害链生机制及其对汶川地震城镇重建的影响[ J ].灾害学,2010,25 (增刊): 278-281.
[ 7 ]崔鹏,庄建琦,陈兴长,等.汶川地震区震后泥石流活动特征与防治对策[ J ].四川大学学报(工程科学版),2010,42 ( 5 ): 10-19.
[ 8 ] Su Pengcheng,Cheng Zunlan,Liu Bintao,Zhao Yan.Renmote Sensing interpretation of debris flow material sources and its distribution characteristics in Miancu gully after Wenchuan earthquake [ C ] //2011 International Conference on Remote Sensing,Environment and Transportation Engineering,2011 : 5214-5217.
[ 9 ]余斌.根据泥石流沉积物计算泥石流容重的方法研究[ J ].沉积学报,2008,26 ( 5 ): 789-796.
[ 10 ]章书成.Oldrich Hungr,Olav Slaymaker.泥石流中巨石冲击力计算,泥石流观测与研究[ M ].北京:科学出版社,1996.
[ 11 ] DZ/T0220-200,泥石流灾害防治工程勘查规范[ S ].
[ 12 ]费祥俊,舒安平.泥石流运动机理与灾害防治[ M ].北京:清华大学出版社,2004.
[ 13 ] Chen Ningsheng,Yue Zhongqi,Cui Peng.A rational method for estimating maximum discharge of a landslide-in duced debris flow : A case study from southwestern China [ J ].Geomorphology,2007,84 : 44-58.
[ 14 ] Crosta G B.Development of risk scenarios for a complex slide [ C ] //Proceedings of VIII International Symposium.Landslides ( ISL ),Cardiff,Wales,2000 : 26-30.
[ 15 ] Suwa H,Yamakoshi T.Estimation of debris flow motion by field surveys [ C ] //Proceedings of the Second Interna tional Conference on Debris-flow Hazards Mitigation.Balkema,Rotterdam,2000 : 245-254.
[ 16 ]唐邦兴,周必凡,吴积善.中国泥石流[ M ].北京:商务印书馆,2000.
[ 2 ]崔鹏,韦方强,何思明,等.5·12汶川地震诱发的山地灾害及减灾措施[ J ].山地学报,2008,26 ( 3 ): 280-282.
[ 3 ]谢洪,钟敦伦,矫震,等.2008年汶川地震重灾区的泥石流[ J ].山地学报,2009,27 ( 4 ): 501-509.
[ 4 ]崔鹏,韩永顺,陈晓清.汶川地震堰塞湖分布规律与风险评估[ J ].四川大学(工程科学版),2009,41 ( 3 ): 35-42.
[ 5 ]庄建琦.汶川震后孕灾环境下泥石流形成机理试验研究[ D ].成都:中国科学院成都山地灾害与环境研究所,2011.
[ 6 ]向灵芝,崔鹏,方华.震后灾害链生机制及其对汶川地震城镇重建的影响[ J ].灾害学,2010,25 (增刊): 278-281.
[ 7 ]崔鹏,庄建琦,陈兴长,等.汶川地震区震后泥石流活动特征与防治对策[ J ].四川大学学报(工程科学版),2010,42 ( 5 ): 10-19.
[ 8 ] Su Pengcheng,Cheng Zunlan,Liu Bintao,Zhao Yan.Renmote Sensing interpretation of debris flow material sources and its distribution characteristics in Miancu gully after Wenchuan earthquake [ C ] //2011 International Conference on Remote Sensing,Environment and Transportation Engineering,2011 : 5214-5217.
[ 9 ]余斌.根据泥石流沉积物计算泥石流容重的方法研究[ J ].沉积学报,2008,26 ( 5 ): 789-796.
[ 10 ]章书成.Oldrich Hungr,Olav Slaymaker.泥石流中巨石冲击力计算,泥石流观测与研究[ M ].北京:科学出版社,1996.
[ 11 ] DZ/T0220-200,泥石流灾害防治工程勘查规范[ S ].
[ 12 ]费祥俊,舒安平.泥石流运动机理与灾害防治[ M ].北京:清华大学出版社,2004.
[ 13 ] Chen Ningsheng,Yue Zhongqi,Cui Peng.A rational method for estimating maximum discharge of a landslide-in duced debris flow : A case study from southwestern China [ J ].Geomorphology,2007,84 : 44-58.
[ 14 ] Crosta G B.Development of risk scenarios for a complex slide [ C ] //Proceedings of VIII International Symposium.Landslides ( ISL ),Cardiff,Wales,2000 : 26-30.
[ 15 ] Suwa H,Yamakoshi T.Estimation of debris flow motion by field surveys [ C ] //Proceedings of the Second Interna tional Conference on Debris-flow Hazards Mitigation.Balkema,Rotterdam,2000 : 245-254.
[ 16 ]唐邦兴,周必凡,吴积善.中国泥石流[ M ].北京:商务印书馆,2000.
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