A New Method for Constructing 3-D Crustal Deformation Field From Single InSAR-LOS Data

Abstract

We propose a new method for retrieving 3-D deformation maps by combining the single Interferometric Synthetic Aperture Radar (InSAR)-line of sight (LOS) data and the physical property of crustal deformation, where the spatial coherence of the crustal deformation direction in elastic senses caused by fault slip is considered. First, fault slip and geometry parameters are inverted based on a simplified elastic dislocation model using the InSAR-LOS data. The continuous 3-D surface deformation direction vectors are then estimated by the model parameters. Finally, with the constraints of direction, InSAR-LOS is transformed into the 3-D components, and the 3-D coseismic deformation field is obtained. We implement the L-band SAR data from Advanced Land Observing Satellite (ALOS)/Phased Array L-band SAR (PALSAR) for the 2008 Wenchuan earthquake to testify our method. For the purpose of comparison, four representative models are constructed, ranging from rough to fine. The experimental results explain that the spatial consistency of our method agrees well with the field investigation and Global Navigation Satellite System (GNSS) observations and shows more application potentials than forward modeling.