Short Note Fault Geometry and Slip Distribution of the 2010 Yushu Earthquakes Inferred from InSAR Measurement

We construct a coseismic deformation interferogram for the April 2010 Yushu earthquakes using ALOS/PALSAR data from the ascending track (path 487). We then infer the trace of the Yushu fault using the coherence image, and we build five fault models for the Yushu fault. To determine the fault geometry parameters that give the best fit to the coseismic interferogram, we apply an elastic dislocation algorithm. Our preferred fault model consists of two faults dipping to the northeast. One strikes ∼N60°W with a dip of 82°; the other strikes ∼N67°W with a dip of 86°. Lastly, we infer the coseismic slip distributions of the Yushu earthquakes by the inversion of the displacement in the line of sight (LOS). The results show that three high-slip concentrations are located at a depth of 5 ∼ 8 km, with a peak slip of 1.32 m at (96.93 E, 33.03 N). The Yushu fault is a left-lateral strike-slip faulting with small northside-up, dip-slip components.