摘要
The authors use GPS data to study coseismic and postseismic deformation of the 21 March 2008 MsT. 3 Yutian earthquake occurred in southern Xinjiang, western China. The coseismic displacements recorded at GPS sites located -100 km north of the fault show clearly a coherent southeastward motion, and reveal that the Yutian earthquake had a significant left-lateral slip component. The GPS postseismic displacements show a different pattern from the one of coseismic displacements, suggesting that the coseismic and postseismic displacements observed at GPS sites were inducedby different sources. Although the Pulu fault has been considered primarily a thrust fault, the spatial distribution of postseismic deformation field of the Yutian earthquake implies that sinistral afterslip might have been triggered along the Pulu fault. The postseismic deformation field suggests active tectonic deformation along the Pulu fault, and attests that this fault is part of the Karokash-Western Altyn Tagh fault system, accommodating the eastward extrusion of the northern Tibetan plateau with respect to the Tarim Basin