HR: 1340h
AN: T43B-1334    [Abstracts]
TI: A Study Of The Tomography And Seismicity In Taipei Basin And Tatun Volcano Regions, Taiwan And Their Structural Implications
AU: * Lin, Y
EM: r94224102@ntu.edu.tw
AF: Institute of Geosciences, No.1, Sec. 4, Roosevelt Rd., Daan, Taipei 106, Taiwan, R.O.C., Taipei, 10617, Taiwan
AU: Wu, Y
EM: ludan@ms9.hinet.net
AF: Institute of Geosciences, No.1, Sec. 4, Roosevelt Rd., Daan, Taipei 106, Taiwan, R.O.C., Taipei, 10617, Taiwan
AU: Lin, C
EM: lin@earth.sinica.edu.tw
AF: Institute of Earth Sciences, No.128, Sec. 2, Academia Rd., Nangang, Taipei 115, Taiwan, R.O.C., Taipei, 11529, Taiwan
AU: Zhao, L
EM: zhaol@earth.sinica.edu.tw
AF: Institute of Earth Sciences, No.128, Sec. 2, Academia Rd., Nangang, Taipei 115, Taiwan, R.O.C., Taipei, 11529, Taiwan
AU: Chang, C
AF: Central Weather Bureau, No.64, Gongyuan Rd., Zhongzheng, Taipei 100, Taiwan, R.O.C., Taipei, 10048, Taiwan
AB: The Taipei Basin with soft deposit in the north of Taiwan has been produced by the motion of the Sanchiao fault. Taipei, the capital of Taiwan, is located at the Taipei Basin and the Tatun volcano group which have volcanism is located adjacent to it. The local seismicity is very low, however, it is a very important topic to understand the seismotectonics of the Taipei Basin and Tatun volcano regions. We combined the seismic data from the records of the Central Weather Bureau Seismic Network (CWBSN) and Taiwan Strong Motion Instrumentation Program (TSMIP) to establish the tomography of Taiwan and then relocated those earthquakes in the study region. Totally, 17,548 events from 1974 to 2006 in the North Taiwan were used for Vp and Vp/Vs tomography. We focus our study on Taipei region that is bounded in latitude 24.91° to 25.31°N and longitude 121.3° to 121.8°E. A total of 339 seismic events with depth less than 100 km from 1977 to 2006 were relocated to study the seismotectonic structures. The pattern of high Vp/Vs ratio coincides with the Sanchiao fault which has made the Taipei Basin, and reveals that the effects of basin amplification affects about several kilometers. There is a zone with high Vp/Vs ratio beneath the Tatun volcano group at the depth of 5~10 kilometer and the strata with low Vp/Vs ratio above this zone appears like an arch. Besides, there are some earthquakes occurred surrounding the high Vp/Vs ratio zone. It may imply that there is a potential region for being full of fluid. It is worth to further analysis about the formation of these earthquakes.
DE: 6982 Tomography and imaging (7270, 8180)
DE: 7200 SEISMOLOGY
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 7270 Tomography (6982, 8180)
SC: Tectonophysics [T]
MN: 2007 Fall Meeting