Abstract:Based on the phase observation report from Xinjiang regional seismic network, we use the finite difference tomography method to invert the P-wave velocity structure of the central and eastern segments of Xinjiang Tianshan mountain. We then acquire the half-annual scale for the evolution of P wave velocity structure before and after the Xinyuan-Hejing earthquake. The results show that the zone of high P-wave velocity difference is produced before the earthquake in the epicenter and the surrounding area at a depth of 12 km, with an anomaly amplitude up to 0.3 km/s. The apparent difference in speed reflects changes of the crust medium by half-annual scale of different time in the same depth of P-wave velocity differential analysis.
LIU Jianming,LI Zhihai,FENG Xueling et al. Evolution of P Wave Velocity Structure before and after the Xinyuan-Hejing MS 6.6 Earthquake in 2012[J]. jgg, 2017, 37(5): 492-496.