Abstract: The stability of bank slope near the reservoir is one of the key factors in dam operation risk identification. Especially at the early stage of water storage, whether the slope in reservoir area near the dam is affected by the rise and fall of the water level is a key concern. In this paper, ascending and descending Sentinel-1A time-series data are used to monitor the deformation of Xiluodu hydropower station on the Jinsha River and its surrounding area. The deformation analysis from January 2020 to December 2020 shows that the main structures of Xiluodu hydropower station and the near-dam bank remain stable, while two landslide deformation areas with large deformation are found in the surrounding areas away from the dam. The results of SBAS-InSAR deformation monitoring are in good agreement with the field survey results. The results show that Sentinel-1A time-series data and SBAS-InSAR technology have broad application prospects in the field of deformation monitoring in alpine and gorge regions, and can provide a new technical means for reservoir deformation monitoring and early warning of dams.

Key words: Xiluodu hydropower station, landslide, SBAS, deformation, time-series analysis

摘要： 水电站近坝库岸边坡稳定是大坝运行风险辨识的关键要素之一，特别是蓄水初期，稳定的近坝库区边坡是否受水位涨落的影响更是需要重点关注。利用升降轨Sentinel-1A时序数据，对金沙江溪洛渡水电站及其周边区域进行了形变监测，从2020年1—12月的形变分析结果可知，溪洛渡水电站主要建筑物和近坝库岸保持稳定，同时也发现远离库岸的坝区周边区域存在两处变形量较大的天然滑坡形变区。通过现场地质勘查与复核，显示SBAS-InSAR技术形变监测结果与现场调查结果具有很好的一致性。研究结果表明，Sentinel-1A时序数据和SBAS-InSAR技术在高山峡谷地区形变监测领域有着较为广阔的应用前景，为水库大坝的库区形变监测预警提供了新的技术手段。

关键词: 溪洛渡水电站, 滑坡, SBAS, 形变, 时序分析