HR: 0830h
AN: S51D-0076    [PDF]
TI: Velocity field in Taiwan area derived from seismic moment tensor before and after the 1999 Chi-Chi earthquake
AU: * Chang, S
EM: sph8801@eq.ccu.edu.tw
AU: Wang, W
EM: seiwhwg@eq.ccu.edu.tw
AB: We apply the method of Haines and Holt to investigate the temporal variation in horizontal velocity field of Taiwan due to co-seismic deformation. We find that long-term (1906-1996) velocity field suggests a NW movement, which is consistent with the convergence direction of the Philippine Sea plate. However, in terms of magnitude, the long-term velocity is only about one tenth of what reported from GPS surveys. Large discrepancy is found in southwestern Taiwan, which implies aseismic creep is significant in that area. After the Chi-Chi earthquake sequence the velocity field has changed from northwest to due west in central Taiwan and southwest in southwestern Taiwan, which suggests counterclockwise rotation is ongoing during the collision of the Eurasian and the Philippine Sea plates.
DE: 7200 SEISMOLOGY
SC: Seismology [S]
MN: 2003 Fall Meeting