Seismic tomography of Taiwan: Improved constraints from a dense network of strong motion stations
Article first published online: 23 AUG 2007
Copyright 2007 by the American Geophysical Union.
Journal of Geophysical Research: Solid Earth (1978–2012)
Volume 112, Issue B8, August 2007
How to Cite
2007), Seismic tomography of Taiwan: Improved constraints from a dense network of strong motion stations, J. Geophys. Res., 112, B08312, doi:10.1029/2007JB004983., , , , , , and (
- Issue published online: 23 AUG 2007
- Article first published online: 23 AUG 2007
- Manuscript Accepted: 6 JUN 2007
- Manuscript Revised: 29 MAY 2007
- Manuscript Received: 12 FEB 2007
 In this study, a large collection of 41,141 S-P times from the untapped records of the Taiwan Strong Motion Instrumentation Program (TSMIP) network is combined with the P and S wave arrival times from the Taiwan Central Weather Bureau Seismic Network (CWBSN) to image the Vp and Vp/Vs structures beneath Taiwan. The records from the 680 TSMIP stations throughout Taiwan in the past 15 years enhance the path coverage and the resolution in the tomography inversions tremendously. Our result for the Vp structure largely confirms previous studies but brings better constraint on the Vp/Vs structure. The colliding Luzon volcanic arc is characterized by a belt of high Vp and highVp/Vs with high seismicity that includes the offshore islands of Lutao and Lanyu and the Coastal Ranges in eastern Taiwan, at the depth between about 13 and 25 km. This highVp/Vs belt can be traced to the subduction zone in the region between Hualian and Ilan in the deeper portion. The shallow portions of the southwestern coastal plain and the Pingtung region are also characterized by a belt of high Vp/Vs with lower seismicity. Most of the events occurred at the base of the high Vp/Vs zones. We suggest that material strength in those regions may be too low to accumulate stress, which may indicate water-saturated young sediments. Finally, the Central Range region is characterized by a low Vp/Vs belt.