3D coseismic deformation of Wenchuan Ms8.0 earthquake with D-InSAR technology and the thrust fault movement model

Abstract

In this paper, 3D coseismic displacements of Wenchuan Ms8.0 Earthquake are obtained by using D-InSAR method and a simulated thrust fault movement model. At first, thirty six L-band PALSAR images of six adjacent ascending tracks are processed with D-InSAR method and get correct coseismic displacements in LOS (line of sight) direction. For recovering 3D coseismic displacement field, the thrust fault movement model of the Long-Men-Shan Fault is formulated based on the field investigations of surface ruptures, which can be used to specify the directions of surface coseismic displacements accordingly. So the 3D coseismic displacement field is then recovered from LOS displacement obtained and relevant formulas for the conversion are given. Horizontal displacements field over the earthquake fault and vertical deformation contour maps are produced based on the 3D coseismic displacements recovered. At last, the coseismic deformation characteristics of this big earthquake are summarized.