Abstract
The Banda Arc-Continent Collision Zone Signifies One Of The Most Seismically Active And Tectonically Intricate Zones. The High Convergence Rate Across The Region, Coupled With The Exceptionally Arcuate Arc And Subducted Slab, Makes It An Ideal Locale For Investigating Interactions Between Plate (Slab) Kinematics And Plastic Flow In The Asthenosphere, Which Can Be Diagnosed By Seismic Anisotropy From Shear Wave Splitting Analyses. In Total, 206 Pairs Of Splitting Measurements Using Teleseismic SKS, SKKS, And PKS, Along With 43 Pairs Using Local S Phases, Are Obtained By Utilizing Broadband Seismic Data From Five Permanent Seismic Stations. To Reduce The Ambiguity In Determining The Origin Of Anisotropy Leading To The Teleseismic Splittings, Which Lack Vertical Resolution, Crustal Anisotropy Is Constrained According To The Sinusoidal Moveout Of Converted S Phases At The Moho Using Receiver Functions. A Layered Anisotropic Structure Based On Joint Analyses Of The Anisotropy Measurements Characterizing Different Depth Layers Suggests The Presence Of Trench-Parallel Flow Both In The Mantle Wedge And The Sub-Slab Region. The Northeastward Motion Of The Slab, Entrained By The Fast-Moving Australian Plate, Deflects Asthenospheric Materials. The Modulation Results In Trench-Parallel Plastic Mantle Flows And Leads To The Steepening Of The Southern Portion Of The Asymmetric Spoon-Shaped Banda Slab. In The Shallower Part Of The Sub-Slab Region, The Northeastward Australian Plate Motion Produces Simple Shear In The Transitional Layer Between The Rigid Lithosphere And The Viscous Asthenosphere. The Shear Deformation Induces Seismic Anisotropy With Resulting Fast Orientations In Accordance With The Plate Motion Direction.
Recommended Citation
S. Li et al., "Layered Mantle Flow Field Associated With Plate Kinematics And Slab Modulation Underneath The Horseshoe-Shaped Banda Arc-Islands," Journal of Geophysical Research: Solid Earth, vol. 129, no. 3, article no. e2023JB027694, American Geophysical Union; Wiley, Mar 2024.
The definitive version is available at https://doi.org/10.1029/2023JB027694
Department(s)
Geosciences and Geological and Petroleum Engineering
Publication Status
Full Access
International Standard Serial Number (ISSN)
2169-9356; 2169-9313
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2024 American Geophysical Union; Wiley, All rights reserved.
Publication Date
01 Mar 2024
Comments
National Science Foundation, Grant 1830644