基于SBAS-InSAR技术的大型滑坡时序微小形变分析及其灾变时间预报  

Time Series Micro-deformation Analysis of Large-scale Landslides Using SBAS-InSAR Technology and Its Catastrophic Failure Time Prediction

作　　者：马闯 缪海波[1] 杨犇 朱隆奇 安广强 杨冰颖 MA Chuang;MIAO Hai-bo;YANG Ben;ZHU Long-qi;AN Guang-qiang;YANG Bing-ying(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]安徽理工大学土木建筑学院,淮南232001

出　　处：《科学技术与工程》2023年第22期9404-9412,共9页Science Technology and Engineering

基　　金：安徽省自然科学基金面上项目(2208085MD97);国家自然科学基金青年科学基金(41502335)。

摘　　要：发育于高山峡谷区的大型滑坡往往具有隐蔽性强、突发性高和危害性大的特点,基于传统监测方法的时序形变数据通常非常匮乏,从而给此类滑坡的早期识别和灾变时间预报带来了极大困难。鉴于此,以西藏自治区江达县波罗乡白格滑坡为例,基于23幅C波段Sentinel-1A升轨雷达影像,利用短基线雷达干涉测量技术(SBAS-InSAR)获取了2017年3月18日至2018年10月3日的垂直方向地表时序形变数据,分析了该滑坡的年平均形变速率、累积形变演化以及典型观测点的累积位移变化,然后利用速度倒数模型对其灾变时间进行了预报。结果表明:白格滑坡灾变前具有明显的形变分区,即强烈变形区、次强烈形变区、一般形变区和基本稳定区,其中强烈形变区的垂直方向年平均形变速率为-39~-67 mm/a;白格滑坡的形变模式概括为后缘滑移牵引—前缘阻滑段渐进滑移—中后部整体变形,与此对应形成了牵引区、阻滑区和主滑区,且阻滑区的形变对降雨较敏感;速度倒数模型预报白格滑坡灾变时间滞后于实际灾变时间8 d,预报效果良好。研究结果表明SBAS-InSAR技术在类似大型滑坡灾变前的形变演化特征分析及灾变时间预报中具有广阔的应用前景。Large-scale landslides in high mountains and steep gorge areas are often characterized by strong concealment,high abruptness and great harmfulness.Time series deformation monitored by traditional methods is usually very scarce,which brings great difficulties to the early identification and catastrophic failure time prediction for this kind of landslides.In view of this,we took the Baige Landslide in Boluo Town,Jiangda County,Tibet as a case study.Based on 23 C-band Sentinel-1A images,time series data of the landslide deformation in the vertical direction from March 18,2017 to October 3,2018 were obtained by using short baseline radar interferometry(SBAS-InSAR).Annual average deformation rates,cumulative deformation evolution characteristics,and cumulative displacements of the typical monitoring points were analyzed.Then the catastrophic failure time was predicted by using the inverse velocity model.The results show as follows.Before the catastrophic failure,the Baige landslide has shown obviously different deformation zones,namely,strong,sub strong,general and stable deformation zone and the average vertical deformation rate ranges approximately from-39 to-67 mm/a in the strong deformation zone.The deformation mode of the Baige landslide can be summarized as“traction caused by trailing edge sliding-progressive sliding of the sliding resistance section in leading edge-whole deformation of the middle and rear part”,which corresponds to the traction,anti-slip,and main-slip area,respectively.Moreover,the deformation in the anti-slip area is sensitive to rainfall.The predicted catastrophic failure time of the Baige landslide lags by 8 d compared with the actual failure time,which shows a reasonable prediction accuracy.This research shows that the SBAS-InSAR technology has broad prospects in deformation evolution analysis before the catastrophic failure of a similar large-scale landslide and its failure time prediction.

关 键 词：大型滑坡 时序微小形变 SBAS-InSAR 灾变时间预报 速度倒数模型 

分 类 号：P642.22[天文地球—工程地质学]