The coseismic InSAR measurements of 2008 Yutian earthquake and its inversion for source parameters

We have obtained the coseismic deformation along line of sight of the 2008 Yutian earthquake, using ALOS PALSAR images and SAR interferomety technique.. Based on the InSAR measurements and the constrained least square method, we studied the source parameters of this big normal event. Four schemes of inversion were constructed, with the emphasis on the effect to slip distribution inversion of the incidence angle and azimuth angle. Our inversion results show that the incidence angle has certain effect on the slip distribution, which means that a substitution of location-dependant incidence angle with constant mean incidence angle will lose some useful slip distribution on fault plane. Our inversion also shows the azimuth angle, however, has almost no obvious effect and it is an optimal choice to use the mean azimuth angle. Our most robust slip distribution can be obtained with the two parameters being location-dependant. In our favored inversion scheme using location dependant angles for both, the maximum slip reaches 3. 2m. Slip is mainly confined to 0 similar to 14 km depth and no evidence of shallow slip deficit. The inverted seismic moment M-0 is 3. 3 X 10(19) N . m, equivalent to an event of magnitude M(w)7. 0.