基于高分影像与InSAR解译的西藏林芝则隆弄高位链式地质灾害发育特征分析

则隆弄沟位于西藏林芝米林县雅鲁藏布江右岸，属于震后影响区，因沟内地形陡峻、物源充足以及水源充沛，1950—2020年期间沟内高位地质灾害活动频繁，沟口村庄和桥梁长期遭受其严重威胁。根据现场调查与无人机航拍，结合多期遥感影像和InSAR数据，对则隆弄沟形成区高风险物源类别、数量以及流通区、堆积区的松散堆积物运动堆积特征进行解译，结果显示:目前则隆弄沟内形成区与流通区陡缓坡交界区域多级多期堆积有大量冰碛物松散物源，流动性较强，区域地质条件、地震活动、气象水文等因素为则隆弄高位链式地质灾害发生提供不稳定的物源结构、良好的临空条件和储藏平台、充足的势动能转换条件以及水动力条件。总结出则隆弄高位地质灾害链形成及演化过程为：高位冰崩（岩崩）-碎屑流-泥石流-堵江堰塞坝（湖）-洪水灾害，其长期具备高易发性和高危险性，后期应加强则隆弄沟高位地质灾害链的监测预警与风险防控。

Analysis of development characteristics of high-elevationchain geological hazard in Zelongnong,Nyingchi, Tibet based on high resolution image and InSAR interpretation

Zelongnong Gully is located on the right bank of YarlungZangbo River in Milin County, Nyingchi, Tibet, which belongs to the post-earthquake affected area. Due to the steep terrain, abundant material sources and abundant water sources in the gully, the high-level geological disasters occurred frequently in the gully during 1950—2020, and the villages and bridges in the gully suffered serious threats for a long time. According to the field investigation and UAV aerial photography, combined with multi-stage remote sensing images and InSAR data, this paper interprets the types and quantity of high-risk sources in the formation area, as well as the movement and accumulation characteristics of loose deposits in the circulation area and accumulation area of Zelongnong Gully. The results show that at present, there are a large amount of glacial moraines of multistage and multi-period accumulation in the interface area between the formation area and the circulation area, and the fluidity is strong. The regional geological conditions, seismicity, meteorology and hydrology and other factors provide unstable source structure, good free space condition and storage platform, sufficient potential energy conversion condition and hydrodynamic condition for the occurrence of Zelongnong high-level chain geological disaster. The formation and evolution process of the high-level geological disaster chain in Zelongnong gully is summarized as follows: high ice collapse (rock collapse) - debris flow - mud-rock flow - blocking river and barrier dam (lake) - flood disaster, which has high vulnerability and high risk in the long term. In the later period, the monitoring, early warning and risk prevention and control of high-level geological disaster chain in Zelongnong Gully should be strengthened.