PALSAR SAR Interferometry for co-seismic deformation monitoring of Wenchuan Earthquake

Satellite differential interferometric synthetic aperture radar (DInSAR) has already demonstrated its potential to map co-, postand inter-seismic deformation since its successful application to the 1992 Landers Earthquake. The Ms 8.0 Wenchuan Earthquake, which occurred on 12 May 2008, was the strongest earthquake to strike China since the 1976 Tangshan earthquake. The devastation of the quake was so widely spread that the PALSAR coverage appeared to be limited and six or more tracks with five or even more frames each before and after the quake are needed in order to map the co-seismic deformation. In this study, six interferograms were generated from ALOS PALSAR Path 471 to 476. The SRTM DEMs with a resolution of three arc seconds were used to remove the topographic phase from the interferograms. The ALOS PALSAR DInSAR results were compared to the ENVISAT ASAR ScanSAR result. It is observed that the ScanSAR DInSAR result was strongly affected by the decorrelation, whereas the PALSAR DInSAR result remained reasonably good due to its longer signal wavelength.