西昌市泸山地区典型火后泥石流特征与成因机制研究——以响水沟左岸3^#支沟为例  

Study on the characteristics and formation mechanism of the typical post-fire debris flow in Lushan area of Xichang City:A case study of 3^#branch on the left bank of Xiangshuigou

作　　者：铁永波[1] 徐如阁[1] 刘洪[1] 王家柱 巴仁基[1] 向安平[1] 杨剑[1] 欧阳渊[1] 张玙[1] 王宏[1] TIE Yongbo;XU Ruge;LIU Hong;WANG Jiazhu;BA Renji;XIANG Anping;YANG Jian;OUYANG Yuan;ZHANG Yu;WANG Hong(Chengdu Geological Survey Center, China Geological Survey, Chengdu 610081, China)

机构地区：[1]中国地质调查局成都地质调查中心,成都610081

出　　处：《中国地质调查》2020年第3期82-88,共7页Geological Survey of China

基　　金：中国地质调查局项目“川西山区城镇灾害地质调查(编号:DD20190640)”;国家自然科学基金面上项目“循环冻融作用下冰碛土的碎化效应及其对泥石流启动的影响试验研究(编号:41772324)”联合资助。

摘　　要：2020年3月30日,四川省凉山州西昌市经久乡发生森林大火,山火燃烧后形成的山火灰和烧焦土体在强降雨作用下极易启动形成泥石流,给西昌市泸山、琼海景区生态环境及当地百姓生命财产安全带来潜在地质灾害风险。以西昌市安哈镇响水沟左岸3#支沟为例,采用野外调查、无人机航拍、地球物理探测、现场及室内实验等手段,对2020年5月1日该沟发生的火后泥石流流体特征、动力学参数及成因机制等开展研究,系统分析了山火及降雨过程对该次火后泥石流形成的影响机制。该成果可为系统认识西昌泸山“3·30”山火地区火后泥石流的运动特征、物源规模、激发雨量及其发展趋势研判提供科学参考。On March 30,2020,a forest fire broke out in Liangshan area of Xichang City in Sichuan Province.After the fire,the ash and burnt soil easily developed into debris flow in case of heavy rainfall,which brought potential geological hazard risks to the ecological environment of Lushan and safety of local people′s lives and properties in Qionghai and Lushan areas.Taking 3#branch on the left bank of Xiangshuigou in Anha Town as an example,the authors conducted field investigation,UAV aerial photography,geophysical exploration,field and indoor experiments to study the fluid characteristics,dynamic parameters and genetic mechanism of the post-fire debris flow on May 1,2020.The features of movement,provenance scale and deduced precipitation were also systematically analyzed.This achievement could provide some reference for the study of the development trend of the post-fire debris flow and the mitigation of disasters in this area.

关 键 词：西昌山火地区 火后泥石流 成因机制 运动特征 防灾减灾 

分 类 号：P642.23[天文地球—工程地质学]