Recent crustal movement and great earthquakes in Qinghai-Tibet sub-plate

Abstract:Crustal movement and incremental-movement data observed repeatedly at GPS stations during 1999–2009 were analyzed to study the effect of two earthquakes of Ms8.1 and Ms8.0 that occurred in 2001 and 2008, respectively, in Qinghai-Tibet sub-plate and its eastern margin. The result revealed certain anomalous pre-earthquake deformation and some large co-seismic changes. Prior to the 2008 Wenchuan Ms8.0 earthquake, the seismogenic Kunlunshan fault zone became a geographic boundary between different regional movements. At the time of the earthquake, there was an average cross-fault crustal shortening of −1.04 m and an average right-lateral strike slip of 0.76 m along the ruptured segment, as well as a strain-energy release of −62. 66 × 10.7