On the effect of horizontal deformation on insar subsidence estimates

Abstract

One of the limitations of InSAR is that it is only capable of measuring a 3D projection of a real deformation vector on the radar line of sight. Therefore it is not possible to retrieve the full displacement vector from a single InSAR measurement. The optimal solution for this limitation is a combination of InSAR measurements from different imaging geometries. However, this solution is not applicable in areas where InSAR data are available in one particular geometry only. In this paper, a new approach will be discussed for 3D decomposition of InSAR deformation measurements for the case of subsidence. We use the hypothesis of a physical relation between horizontal displacement and vertical deformation. Using this hypothesis, we propose an iterative strategy for 3D decomposition of InSAR subsidence measurements. The proposed approach is tested on the PSI results of a complex subsidence field in Friesland, the Netherlands. Finally, the results are validated by comparison with available leveling data.