澜沧江德钦段地质灾害隐患InSAR识别与形变监测

Identification and Deformation Monitoring of Potential Geotechnical Hazards in the Deqin Section of the Lancang River,China

青藏高原东南缘地形起伏大,构造运动活跃,发育着冰川和冻土,地质灾害种类多且发生频繁。为研究该地区地质灾害的分布特征和运动规律,选取澜沧江德钦段作为研究区,基于一个轨道的ALOS-2卫星和3个轨道的Sentinel-1A卫星数据,利用Stacking-InSAR和DS-InSAR技术分别进行了研究区大范围地质灾害调查和典型泥石流物源区的时间序列监测,并采用奇异谱分析(SSA)提取了形变的周期项特征。结果表明:研究区内共存在670个形变区域,石冰川占大部分,位于海拔较高的山顶,距澜沧江5 km的范围内有27个滑坡;选取的典型泥石流物源区2017~2022年形变时间序列呈线性趋势,其中石冰川周期项形变与降水量和气温存在相关性。

The southeastern Qinghai-Xizang Plateau has significant topographical variations,active tectonic movements and developed glaciers and permafrost.A variety of geotechnical disasters occur frequently in this region.In order to study the distribution characteristics and movement patterns of geotechnical hazards in this region,the Deqin section of the Lancang River was selected as the research area.Based on the data form ALOS-2 satellite of one track and Sentinel-1A satellite of three tracks,large-scale geotechnical hazards investigation in the study area were conducted using Stacking-InSAR technology,while time-series monitoring of typical debris flow source areas was carried out using DS-InSAR technology.Singular spectrum analysis(SSA)was employed to extract the periodic characteristics of deformation.The results show that there are a total of 670 deformation areas in the study area,most of which are rock glaciers located on the mountain tops of high elevations,and 27 landslides are distributed within a 5 km-distance from the Lancang River;the deformation time series of the selected typical debris flow source area from 2017 to 2022 shows a linear trend;both precipitation and temperature are correlated with the periodic deformation of the rock glacier from this source area.