基于SBAS-InSAR技术的舟曲县潜在滑坡灾害早期识别及降水相关性分析

近年来，甘肃省舟曲县白龙江两岸古滑坡的发育复活呈现活跃趋势，下游已经开发建设的大量民用设施受其威胁，因此这些滑坡的早期识别成为该地区地质灾害预防需要关注的重要课题。基于Sentinel-1A降轨SLC数据，采用SBAS-InSAR技术，对舟曲县，尤其是白龙江沿岸滑坡灾害隐患进行早期识别，获取舟曲县潜在滑坡灾害点列表，并划分其风险等级，重点分析大蠕滑量的四个典型滑坡的时序形变过程，总结舟曲县滑坡发育与降水之间的相互关系，研究结果表明：舟曲县白龙江干流及支流河谷区西北-东南方的老滑坡体均发生了一定程度的滑动，共识别出高风险等级坡体8个，分别为寺儿沟、立节北山、杭嘎村、锁儿头、三眼峪、南峪、大川乡—两河口及曲告纳乡滑坡，严重威胁15个村镇的居民生命财产安全。其中锁儿头、三眼峪和南峪滑坡的形变最为严重，对其重点分析的结果显示，监测时段内平均形变速率达-80.1421.48mm/y，形变量达-482.01493.31mm，坡体在未来复发的可能性较大，而且，近年来逐渐增加的降水更有可能促使其提前复发。舟曲县典型滑坡的后缘形变与降水量具有一定的相关性，滑坡的发生受降水影响极大，同时，地质构造、地形地貌、地震、地层岩性等也对滑坡的发生具有一定影响。

Early Identification of Potential Landslide Hazards and Precipitation Correlation Analysis in Zhouqu County Based on SBAS-InSAR Technology

In recent years, the development of ancient landslides on both sides of the Bailong River in Zhouqu County, Gansu Province has shown an active trend of resurrection, and a large number of civil facilities have been developed and constructed downstream, so its early identification has become a topic of general concern for geological disaster prevention.In this paper, we use Sentinel-1A descending track SLC data and SBAS-InSAR technology to make early identification of landslide hazard potential in Zhouqu County, especially along the Bailong River, obtain a list of potential landslide hazard sites in Zhouqu County, classify their risk levels, and focus on analyzing four typical landslide temporal deformation processes with large creeping slide volume, and summarize the relationship between landslide development and precipitation in Zhouqu County.The study shows that the old landslides along the main stream of Bailong River and the tributary valley area of Zhouqu County in the northwest-southeast have all slid to some extent, and a total of 8 high-risk grade slopes have been identified, namely, Siergou, Lijiebeishan, Hangga Village, Suoertou, Saneyanyu, Nanyu, Dachuan to Lianghekou and Qugaona Township landslides, which seriously threaten the life and property safety of residents in 15 villages and towns.Among them, the most serious deformation of the Suoertou, Sanyanyu and Nanyu landslide is the giant ancient landslide which is the focus of this paper. The average deformation rate during the monitoring period is -80.14~21.48mm/y, and the deformation variable is -482.01~493.31mm. The landslides has a higher possibility of recurrence in the future, and the gradual increase of precipitation in recent years may contribute more to its early recurrence.Analysis of typical landslides in Zhouqu County reveals that there is a correlation between landslide trailing edge deformation and precipitation, and the occurrence of landslides is greatly influenced by precipitation, meanwhile, geological structure, topography and geomorphology, earthquakes and stratigraphic lithology also have some influence on the occurrence of landslides.