Investigating the lithospheric velocity structures beneath the Taiwan region by nonlinear joint inversion of local and teleseismic P wave data: Slab continuity and deflection
Journal
Geophysical Research Letters
Journal Volume
41
Journal Issue
18
Pages
6350-6357
Date Issued
2014
Author(s)
Huang H.-H. et al.
DOI
GPRLA
Abstract
The interaction between two flipping subduction systems shapes the complicated lithospheric structures and dynamics around the Taiwan region. Whether and in what form the Eurasian Plate subducts/deforms under Taiwan Island is critical to the debate of tectonic models. Although an east dipping high-velocity anomaly down to a depth below 200 km has been reported previously, its detailed morphology remains uncertain and leads to different interpretations. With a two-step strategy of nonlinear joint inversion, the slab images of the Eurasian Plate were retrieved in a geometry that is hyperthin in the south, becoming massive and steeper in the central, and severely deformed in the north. The possible depth and dimension of a slab break were also investigated through synthetic tests of whether the slab had torn. Moreover, the slab deflection found at ~23.2°N latitude seems to correspond to where the nonvolcanic tremors and recent NW-SE striking structures have occurred in southern Taiwan. Key Points High-resolution lithospheric images are retrieved by a two-step joint inversionThree-dimensional geometry of the east subducting slab under Taiwan is establishedA possible slab deflection is observed at around latitude 23.2°N ©2014. American Geophysical Union. All Rights Reserved.
Subjects
Geometry; Seismology; Tectonics; Joint inversion; Seismic tomography; Seismotectonics; Slab geometry; Taiwan orogeny; Plates (structural components); data set; geometry; geomorphology; lithosphere; nonlinearity; orogeny; P-wave; plate tectonics; seismic tomography; seismotectonics; slab; subduction zone; teleseismic wave; three-dimensional modeling; velocity structure; Taiwan
Publisher
Blackwell Publishing Ltd
Type
journal article