Improved seismic tomography offshore northeastern Taiwan: implications for subduction and collision processes between Taiwan and the southernmost Ryukyu
Speaker: Zhang, Jun-Wei
Abstract
Most of the earthquakes occurred in the offshore northeastern Taiwan, but the seismic stations are located on land, which was unable to make a good tomography of subsurface. In this study, in order to expand the source-station pathes coverage, the study uses the earthquake records from CWBSN and TSMIP, and also uses the OBS and JMA data. This study mainly discusses the offshore northeastern Taiwan tomography, which can be observed that the resolution of the tomography in this study is more clearly than Wu’s (2007). In this tomography, it can be observed that the subduction lab is a high Vp area, surrounding areas are low Vp and a big high Vp/Vs area elongate from subduction lab. It might be the partial melting part of the subduction lab. Comparing with seismic profiles, it can see that the Sansing fault was located on a low Vp and High Vp/Vs area, which means that might have hydrothermal solution there.
Reference
Wu, Y. M., J. B. H. Shyu, C. H. Chang, L. Zhao, M. Nakamura, and S. K. Hsu (2009). Improved seismic tomography offshore northeastern Taiwan: Implications for subduction and collision processes between Taiwan and the southernmost Ryukyu, Geophys. J. Int. 178, 1042–1054, doi: 10.1111/j.1365-246X.2009.04180.x
Wu, Y. M., C. H. Chang, L. Zhao, J. B. H. Shyu, Y. G. Chen, K. Sieh, and J. P. Avouac (2007). Seismic tomography of Taiwan: Improved constraints from a dense network of strong-motion stations. Journal of Geophysical Research, 112, B08312, doi:10.1029/2007JB004983.