The Moho discontinuity beneath Taiwan: Receiver functions and migration imaging
Date Issued
2014
Date
2014
Author(s)
Chang, Hsin-Dieh
Abstract
We determine the depth variations of the Moho discontinuity beneath Taiwan from receiver functions and migration imaging. Taiwan is a young (~6.5 Ma) orogenic zone as a consequence of oblique collision between the Philippine Sea Plate and the Eurasian Plate. Much debate has centered on various models explaining the tectonic evolution of Taiwan orogeny. To that end, the depth of the Moho discontinuity is a key parameter for better understanding crustal deformation patterns associated with orogenic processes.
In this study, we delineate the Moho depth variations by analyzing converted and scattered seismic waves. We analyze waveform data from teleseismic events recorded at the Broadband Array in Taiwan for Seismology (BATS) and temporary seismic stations of TGC-line and TGS-line of Taiwan Integrated GEodynamics Research project (TAIGER). We selected teleseismic events of magnitude larger than 5.5 and epicentral distance between 30 and 90 degrees.
Our receiver function results show that there are likely more than one converted phases presenting within crustal depths beneath the stations we examine, suggesting the possible presence of multiple layering at least locally. Our migration images further reveal significant Moho topography across central and southern Taiwan, with the deepest Moho located under the Central Range. These results are generally consistent with the Moho location determined by 7.5 km/s contour in 3-D P-wave velocity model. Finally, we also observe a strong mid-crust discontinuity, perhaps associated with seismic anisotropy.
In this study, we delineate the Moho depth variations by analyzing converted and scattered seismic waves. We analyze waveform data from teleseismic events recorded at the Broadband Array in Taiwan for Seismology (BATS) and temporary seismic stations of TGC-line and TGS-line of Taiwan Integrated GEodynamics Research project (TAIGER). We selected teleseismic events of magnitude larger than 5.5 and epicentral distance between 30 and 90 degrees.
Our receiver function results show that there are likely more than one converted phases presenting within crustal depths beneath the stations we examine, suggesting the possible presence of multiple layering at least locally. Our migration images further reveal significant Moho topography across central and southern Taiwan, with the deepest Moho located under the Central Range. These results are generally consistent with the Moho location determined by 7.5 km/s contour in 3-D P-wave velocity model. Finally, we also observe a strong mid-crust discontinuity, perhaps associated with seismic anisotropy.
Subjects
臺灣造山帶
莫荷面深度
接收函數
轉型波
移位成像
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-103-R01241301-1.pdf
Size
23.54 KB
Format
Adobe PDF
Checksum
(MD5):f803f26cb3322acfa54106deb3979a14