Deformation Monitoring by Long Term D-InSAR Analysis in Three Gorges Area, China

After the Three Gorges Dam began to function in China in 2003, the water level of the Yangtze River in Three Gorges area rose more than 100 meters. The impact of the man-made reservoir caused by the dam on the surroundings is becoming the object of several studies. In this paper we make use of two long term D-InSAR techniques, the quasi-permanent scatterer technique (QPS) and the Stanford Method for Persistent Scatterer (StaMPS), to measure the deformation trends in Badong, Three Gorges area, China. The results obtained by the two processing tools with the same focused and co-registered data sets are analyzed and compared. Two subsidence areas are identified by both techniques. However, since the QPS analysis is able to process partially coherent targets, many more points are extracted than in StaMPS, and more information can be retrieved.