Landslide is a global environmental geological hazard caused by natural or human activities. Since the impoundment of the Three Gorges reservoir area, the geological disasters such as collapses, landslides and other kinds of geological disasters increased obviously due to the periodic fluctuation of the water level in the Yangtze River. Wanzhou District is located in the center of the Three Gorges Reservoir Area, which plays an important role in the prevention and control of geological hazards in the whole Three Gorges Reservoir Area. This is because a large number of deep bedrocks old landslides are distributed among this region, such as Taibaiyan ancient landslide, Caojiezi ancient landslide, Anlesi ancient landslide, Pipaping ancient landslide, and Diaoyanping ancient landslide. In this study, Quasi-Persistent Scatterers InSAR (QPS-InSAR) time-series method is proposed to identify and monitor the ancient landslides in Wanzhou. In this method, the High-coherent test is applied to Quasi-Persistent Scatterers (PSC) selection, and PSC and persistent scatterer are combined to improve the density of measurement points in vegetation area. The QPS-InSAR method is also characterized by the appropriate combination of differential interferograms produced by a Minimum Spanning Tree and the employment of the phase triangulation algorithm to estimate the optimal phase. This technique was performed on 8 scenes of L-band ALOS PALSAR ascending data acquired during 2015–2018, then deformation rate maps and time series for ancient landslide were generated, which were applied to retrieve time series displacement for the large-scale landslide in Wanzhou District. The experiment results show that there are obvious landslide deformation patterns detected in this region with displacement velocity larger than − 21 mm/yr during the observation period. Finally, the influencing factors such as geological conditions, distribution of rainfall and reservoir water level change in the Three Gorges Reservoir area, and deformation mechanism of Wanzhou landslide are analyzed. The monitoring results will help the local government to carry out regular landslide inspection and strengthen landslide disaster early warning.

滑坡是由自然或人类活动引起的全球性环境地质灾害。三峡库区蓄水以来，由于长江水位周期性波动，崩塌、滑坡等地质灾害明显增多。万州区位于三峡库区的中心，对整个三峡库区的地质灾害防治具有重要作用。这是因为该地区分布着大量深基岩古滑坡，如太白岩古滑坡、草街子古滑坡、安乐寺古滑坡、琵琶坪古滑坡、吊岩坪古滑坡等。在这项研究中，针对万州古滑坡的识别和监测，提出了准持续散射干涉SAR(QPS-InSAR)时间序列方法。该方法将高相干测试应用于准持久散射体（PSC）选择，将PSC和持久散射体相结合，提高植被区测量点的密度。QPS-InSAR 方法的另一个特点是通过最小生成树产生的微分干涉图的适当组合和使用相位三角测量算法来估计最佳相位。该技术对2015-2018年期间获得的L波段ALOS PALSAR上升数据的8个场景进行了处理，然后生成了古滑坡的变形率图和时间序列，应用于万州区大型滑坡时间序列位移反演。实验结果表明，在观测期间，该区域存在明显的滑坡变形模式，位移速度大于−21 mm/yr。最后，对三峡库区的地质条件、降雨分布和库水位变化、万州滑坡变形机制等影响因素进行了分析。监测结果将有助于当地政府定期开展滑坡检查，加强滑坡灾害预警。分析了三峡库区的地质条件、降雨分布和库水位变化、万州滑坡变形机制等影响因素。监测结果将有助于当地政府定期开展滑坡检查，加强滑坡灾害预警。分析了三峡库区的地质条件、降雨分布和库水位变化、万州滑坡变形机制等影响因素。监测结果将有助于当地政府定期开展滑坡检查，加强滑坡灾害预警。