g. 3. (a) ALOS differential interferogram (in radar coordinates) superimposed on a SAR amplitude image. One fringe cycle corresponds to a displacement of about 11.8 cm. Acquisition dates are 22 March 2010 and 7 May 2010, i.e., one repeat cycle (46 days) covering the seismic event. (b) Ground deformation map (in LOS) corresponding to the interferogram in (a).
The joint use of both CSK and ALOS data gives us complementary information about the occurred ground changes. Full spatial coverage of the ALOS interferogram allows understanding that the displacements are confined in a very narrow area nearby the PFS and rapidly decay moving away from the fault trace (Fig. 3). On the other hand, CSK data allow analyzing the displacement field with a greater detail (Fig. 2b and d). However, the smaller operational wavelength of CSK data introduces more significant decorrelation noise in the interferograms (Zebker & Villasenor, 1992), thus reducing the spatial coverage. Accordingly, the combined use of ALOS and CSK data allows us to retrieve the whole deformation pattern with an overall satisfactory level of detail.
4. Slip distribution models