Synthetic normal faulting of the 9 January 2008 Nima (Tibet) earthquake from conventional and along-track SAR interferometry

We use Synthetic Aperture Radar Interferometry (InSAR) to derive the coseismic deformation field of the 9 January 2008 Nima (Tibet) earthquake. The results show an asymmetric deformation pattern, consistent with normal faulting on a NW-dipping fault plane. The complex line-of-sight (LOS) fringe pattern suggests that a second, synthetic fault in the hanging wall of the mainshock rupture slipped during the event, most likely during the largest aftershock. We use conventional and along-track InSAR data to invert for the geometry and the slip-distribution on the two fault planes. The focal mechanisms of the mainshock and its largest aftershock show normal faulting with a small left-lateral strike-slip component near the NE-trending Riganpei Cuo fault, which is consistent with our InSAR observation and inversion result. This event suggests that normal faulting in addition to previously established conjugate strike-slip deformation in the region contributes to the internal deformation of central Tibet. Citation: Sun, J., Z. Shen, X. Xu, and R. Burgmann (2008), Synthetic normal faulting of the 9 January 2008 Nima (Tibet) earthquake from conventional and along-track SAR interferometry, Geophys. Res. Lett., 35, L22308, doi: 10.1029/2008GL035691.