丹巴县“6·17”阿娘寨村滑坡体特征及成因初步分析

2020年6月17日凌晨3点20分左右四川甘孜州丹巴县半扇门镇梅龙沟发生泥石流,阻断小金川河,形成堰塞湖,造成S303烂水湾段道路中断和阿娘寨村山体滑坡。通过现场勘查、无人机航拍和模型计算等方法,基于该区域地质环境和气象条件分析,揭示了阿娘寨滑坡体变形特征和成因,在此基础上预测滑坡发展趋势。研究结果表明:阿娘寨滑坡为土质滑坡,老滑坡体的复活与演变是内外动力综合作用的结果。频繁的地质构造活动破坏了岩土体稳定性,降雨和渗流降低了土体强度,泥石流冲刷淘蚀坡脚直接导致滑坡体启动。根据滑坡体变形特征,推测无重大地质构造活动和降水条件下,滑坡体会逐渐变形后渐趋于平衡。故汛期时应持续监测,及时预警,加强该地区防灾减灾措施。

Preliminary Analysis on the Characteristics and Causes of Landslide in "6.17" Aniangzhai Village in Danba County

At 3:20 am on June 17, 2020, a debris flow occurred in Meilong gully, Banshanmen Town, Danba County, Sichuan Province, blocking the Xiaojinchuan River and forming a barrier lake, which damaged the S303 road and caused a landslide in Aniangzhai. Through field investigation, drone aerial photography and hydrological calculation based on the analysis of the geological environment and meteorological conditions in this region, the deformation characteristics and causes of the Aniangzhai landslide were revealed and the development trend of the landslide was predicted. The research results show that the landslide is a soil landslide, and the initiation of the landslide is the result of the combined action of internal and external dynamics. Frequent geological tectonic activities destabilize rock and soil mass, the rainfall and seepage reduce the strength of the soil, and the debris flow scours the foot of the slope, which directly triggered the landslide initiation. According to the deformation characteristics of the landslide, it is found that without major geological tectonic activities and precipitation conditions, the landslide body will gradually deform and then tend to balance. Therefore, continuous monitoring during the flood season and timely warning should be taken to strengthen disaster prevention and mitigation in the region.