Deformation monitoring in Hanyuan reservoir resettlement of Pubugou Hydropower Station using PS-InSAR

Abstract

Interferometric synthetic aperture radar (InSAR) is a very effective technique for measuring surface deformation, but the temporal and geometrical decorrelation and atmospheric disturbances can strongly compromise the accuracy of the results. Persistent scatterer InSAR (PS-InSAR) overcomes the decorrelation and atmospheric disturbances problem by identifying resolution elements whose echo is dominated by a single scatterer in a series of interferograms. The results obtained by PS-InSAR technique are not the field deformation information but persistent scatterers deformation. In this paper, PS-InSAR is used to investigate surface deformation caused by landslide hazards in Hanyuan reservoir resettlement, China. The subsidence map derived from Envisat ASAR data between May 2008 and Oct 2009 reveals the spatial extent of the deformations and subsidence velocity. The experimental results show that there are instable areas which are located in the Middle of new Hanyuan county. The average deformation rate of the instable areas is over - 20mm. The Upper right and Lower left of new Hanyuan county are relatively stable.