The 2007 Ali Earthquake Inversion from Ascending and Descending InSAR Observations

doi:10.11947/j.AGCS.2015.20140349

Abstract

Abstract: On 5th May, 2007, a M_w6.1 earthquake occurred in the Ali region, China. In this study, ascending and descending tracks of ASAR images collected by Envisat satellite are employed to derive the precise coseismic surface displacements, then nonlinear MPSO algorithm and linear least-square method with elastic half-space dislocation model are used to estimate the fault geometry and coseismic slip distribution. Our model suggests that the distributed slip mode can fit the observations very well. The earthquake fault is a normal fault with a strike of 158°, a dip of 43° and dipping to southwest. The slip mainly occurs within 7~12 km along the orientation, with a maximum slip of 0.3 m at a depth of 9 km. The determined geodetic moment is 1.24×10¹⁸ Nm, which is consistent with seismological results.

Key words: Ali earthquake, InSAR, slip distribution inversion, focal mechanism

CLC Number:

P225.1

WEN Yangmao, XU Caijun, LIU Yang, FENG Wanpeng, LI Zhicai. The 2007 Ali Earthquake Inversion from Ascending and Descending InSAR Observations[J]. Acta Geodaetica et Cartographica Sinica, 2015, 44(6): 649-654.

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