TY - JOUR
T1 - Fault geometries illuminated from seismicity in central Taiwan
T2 - Implications for crustal scale structural boundaries in the northern Central Range
AU - Gourley, Jonathan R.
AU - Byrne, Timothy
AU - Chan, Yu Chang
AU - Wu, Francis
AU - Rau, Ruey Juin
N1 - Funding Information:
We would like to thank our reviewers for their thoughtful and careful comments that helped us improve this paper significantly. We gratefully acknowledge the Tectonics Program of the Earth Sciences Division (grant EAR 9903248) as well as the East Asia & Pacific Program of the Office of International Science and Engineering at the National Sciences Foundation.
Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2007/12/20
Y1 - 2007/12/20
N2 - Data sets of collapsed earthquake locations, earthquake focal mechanisms, GPS velocities and geologic data are integrated to constrain the geometry and kinematics of a crustal block within the accreted continental margin rocks of Taiwan's northeastern Central Range. This block is laterally extruding and exhuming towards the north-northeast. The block is bound on the west-southwest by the previously recognized Sanyi-Puli seismic zone and on the east by a vertical seismic structure that projects to the eastern mountain front of the Central Range. Focal mechanisms from the Broadband Array of Taiwan Seismicity (BATS) catalog consistently show west-side-up reverse displacements for this fault zone. A second vertical structure is recognized beneath the Slate Belt-Metamorphic Belt boundary as a post-Chi-Chi relaxation oblique normal fault. BATS focal mechanisms show east-side-up, normal displacements with a minor left-lateral component. The vertical and lateral extrusion of this crustal block may be driven by the current collision between the Philippine Sea Plate and the Puli basement high indenter on the Eurasian Plate and/or trench rollback along the Ryukyu subduction zone. In addition, the vertical extent of the two shear zones suggests that a basal décollement below the eastern Central Range is deeper than previously proposed and may extend below the brittle-ductile transition.
AB - Data sets of collapsed earthquake locations, earthquake focal mechanisms, GPS velocities and geologic data are integrated to constrain the geometry and kinematics of a crustal block within the accreted continental margin rocks of Taiwan's northeastern Central Range. This block is laterally extruding and exhuming towards the north-northeast. The block is bound on the west-southwest by the previously recognized Sanyi-Puli seismic zone and on the east by a vertical seismic structure that projects to the eastern mountain front of the Central Range. Focal mechanisms from the Broadband Array of Taiwan Seismicity (BATS) catalog consistently show west-side-up reverse displacements for this fault zone. A second vertical structure is recognized beneath the Slate Belt-Metamorphic Belt boundary as a post-Chi-Chi relaxation oblique normal fault. BATS focal mechanisms show east-side-up, normal displacements with a minor left-lateral component. The vertical and lateral extrusion of this crustal block may be driven by the current collision between the Philippine Sea Plate and the Puli basement high indenter on the Eurasian Plate and/or trench rollback along the Ryukyu subduction zone. In addition, the vertical extent of the two shear zones suggests that a basal décollement below the eastern Central Range is deeper than previously proposed and may extend below the brittle-ductile transition.
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U2 - 10.1016/j.tecto.2007.08.013
DO - 10.1016/j.tecto.2007.08.013
M3 - Article
AN - SCOPUS:36549040451
VL - 445
SP - 168
EP - 185
JO - Tectonophysics
JF - Tectonophysics
SN - 0040-1951
IS - 3-4
ER -