四川省盐源县玻璃村“7·19”特大滑坡灾害应急科学调查

Emergency Investigation to 7·19 Landslide Disaster in Boli Village,Yanyuan County,Sichuan,China

2018年7月19日四川省盐源县玻璃村突发特大土质滑坡,损毁房屋65户186间,造成直接经济损失1300万元。由于预警预报及时,区域内97户437人成功避险,无人员伤亡。通过对滑坡区域进行现场调访、无人机航拍、实验分析等方法,对该区域的地质、降雨、滑动变形特征和过程进行分析,研究了滑坡的成因,预测其发展趋势,提出减灾建议。滑坡是在区域脆弱地质环境背景,陡倾地形的影响,降水和地表径流联合作用下,古滑坡堆积体复活的结果;滑坡堆积体存在转化为泥石流灾害的风险;过去排查的地质灾害隐患点的科学合理性需要进一步研究确认。盐源县玻璃村滑坡是典型的避险成功案例,县、乡、村、组4级监测网络的群测群防工作对此次成功的灾害避险起到重要作用,可为相似灾害的避险工作提供借鉴。同时应对流域滑坡泥石流采取工程措施,完成灾害体的综合整治。

On July 19,2018,a catastrophic soil landslide occurred in the Boli Village,Yanyuan County,Sichuan Province,and damaged 186 rooms of 65 houses,causing a direct economic loss of 13 million yuan.Due to the early detection of landslide from the visible cracks in the houses before the occurrence of the major landslide and the help of community-based early warning system,the dwellers(437 people in the region)were successfully evacuated with no casualties.Questionnaire survey,aerial photography and experimental analysis coupled with geological and precipitation data were analyzed for understanding its initiation process and deformation trends.Based on the detailed analysis,prevention and mitigation measures were proposed.The landslide is the result of the resurrection of the ancient landslide deposits under the influence of the steep fragile topography and the coupled action of precipitation and surface runoff.The landslide deposits still have the risk of being converted into debris flow hazards.The scientific rationality of the hidden danger points needs further research and confirmation.The landslide of Boli Village in Yanyuan County is a typical case of mass monitoring and prevention system with public participation.This system plays an important role in disaster warning and risk avoidance in geological disaster-prone areas in China.Through a good publicity and training about preliminary judgments on disasters,continuous inspections,notifications and application of self-help methods,it establishes a smooth communication network and provides favorable conditions for monitoring,early warning and risk avoidance of geological disasters such as landslides.The system in the study area can be divided into the county,township,village and group monitoring networks,which can provide future reference for similar disasters.Furthermore,engineering measures proposed should be considered to minimize further risk of the residual loose deposits at the trailing edge of the landslide deposits.The comprehensive control of the disaster body in this region should be improved.