Short-period Teleseismic Full-waveform Tomography for the Lithospheric Structure in Southern Taiwan
Abstract
Along the southeast coast of Taiwan, the Philippine Sea and Eurasian plates are converging at a rate of ~8 cm/year. The oblique plate collision leads to the formation of several nearly NS-trending geological structures, such as the Central Range, Longitudinal Valley and Luzon Arc. The dynamics of the orogenic processes as well as the deep structure beneath Taiwan remain topics of debate. Recently, efficient tomography techniques, collectively referred to as box tomography, have been developed which use short-period (5 s) teleseismic (30°-90°) records as well as hybrid algorithms for accurate wavefield simulation at different scales to image deep (~100 km) structures on regional scale (< 300 km) with high resolution. In this study, we apply the box tomography method to a densely distributed linear seismic array of ~140 km long across southern Taiwan. We use vertical- and radial-component short-period records from five teleseismic events of magnitudes Mw6.5 and above to obtain P- and S-velocity models down to ~100 km beneath the array. Our models are compared with the existing ones and interpreted in terms of possible geodynamical processes. Our results provide new and reliable seismic evidence for understanding the mechanism of plate collision and mountain building processes in southern Taiwan.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.S22B..07Z