结合星载地基InSAR分析的四川新磨村滑坡早期识别与灾后监测  

Integration between ground based and satellite SAR data in analysis:a casestudy of Xinmo village landslide in Mao county,Sichuan province

作　　者：白泽朝 吕森 曹琨 王彦平 BAI Ze-chao;Lü Sen;CAO Kun;WANG Yan-ping(School of Information Science and Technology,North China University of Technology,Beijing 100144,China)

机构地区：[1]北方工业大学信息学院,北京100144

出　　处：《地球物理学进展》2020年第5期1637-1643,共7页Progress in Geophysics

基　　金：国家重点研发计划资助(2018YFC1505103);国家自然科学基金重点国际合作研究项目(61860206013)资助。

摘　　要：滑坡是我国主要的地质灾害之一,广域范围滑坡灾害体的早期识别及局部重点区域近实时监测是地质灾害防治工作中的一项重要任务.本文通过四川茂县新磨村滑坡这一典型案例,采用星载InSAR技术对广域范围滑坡进行早期识别,并利用地基InSAR技术对局部重点滑坡近实时监测,探索星载InSAR技术和地基InSAR技术联合监测应用模式.在星载InSAR技术滑坡早期识别阶段,为了准确还原滑坡加速下滑过程,采用分级构网策略加密PS点,在时间域上低通滤波获取非线性形变信息.针对地基InSAR技术传统选点方法误选率高、合理性差等问题,设计了三阈值优化算法,提取分布合理的有效测量点.结果表明:星载InSAR技术成功识别出茂县滑坡不稳定坡体,且在滑坡发生前,不稳定坡体有加速下滑现象;在滑坡发生后,地基InSAR技术获取了滑坡体完整的形变信息,在滑源区和流通区存在两处明显形变区域.星载InSAR技术和地基InSAR技术联合监测在滑坡形变的不同阶段多尺度识别出变形区域,可在滑坡稳定性调查和评价中发挥重要作用.Landslide is one of the major geological disasters in China.The early identification of hidden dangers of landslide hazards in the wide area and the near real-time monitoring of local key areas are a key task in the prevention and control of geological disasters.Based on the typical case of Xinmo village landslide in Mao county,Sichuan province,the satellite InSAR is used to identify the wide-area landslide early,and the ground-based InSAR is used to monitor the local landslide in near real-time.The joint application model of satellite InSAR and ground-based InSAR is explored.In the early stage of satellite InSAR landslide identification,in order to accurately restore the landslide acceleration and decline process,low-pass filtering in the time domain is used to obtain nonlinear deformation information.And hierarchical network construction method is used to encrypt PS points.Aiming at the problems of high misclassification rate and low rationality of the traditional ground-based InSAR selection method,a three-threshold optimization algorithm is designed to extract effective observation points with reasonable distribution.The results show that the satellite InSAR successfully identifies the unstable slope of Mao county landslide,and there was an accelerated downslide before the landslide occurred.The ground-based InSAR acquires the complete deformation information of the landslide,and there are still two local decline after the landslide occurs.Joint monitoring of satellite InSAR and ground-based InSAR can identify deformation zones at different stages and multiple scales of landslides,which can play an important role in the investigation and evaluation of landslide stability.

关 键 词：星载/地基InSAR 联合测量 非线性形变 选点算法 茂县滑坡 

分 类 号：P228[天文地球—大地测量学与测量工程]