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Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
Published on: August 7, 2017
The subduction zone flow field from seismic anisotropy: a global view
Maureen D Long1, Paul G Silver
1Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015, USA. long@dtm.ciw.edu
Science (New York, N.Y.)
|January 19, 2008
Summary
Mantle flow during subduction is better understood by analyzing seismic anisotropy. Trench migration velocity influences mantle flow patterns beneath and within the mantle wedge, interacting with convergence-driven flow.
Area of Science:
- Geophysics
- Seismology
- Tectonics
Background:
- Subducting slab morphologies are well-understood, but associated mantle flow remains unclear.
- Seismic anisotropy, observed via shear wave splitting, offers insights into mantle flow.
Purpose of the Study:
- To characterize mantle flow patterns associated with subduction.
- To investigate the relationship between trench migration and mantle flow.
Main Methods:
- Compiled shear wave splitting observations from 13 subduction zones.
- Analyzed seismic anisotropy variations in relation to trench migration velocity (|V(t)|).
Main Results:
- Observed systematic variations in mantle-wedge and subslab anisotropy with trench migration velocity.
- Identified trench-parallel flow, driven by trench motion, as dominant beneath the slab.
- Showed that this trench-parallel flow magnitude scales with |V(t)|.
- Demonstrated interaction between trench-parallel flow and convergence-driven corner flow in the mantle wedge.
Conclusions:
- Trench migration velocity is a key factor controlling mantle flow during subduction.
- The relative influence of trench-parallel and corner flow depends on the magnitudes of |V(t)| and convergence velocity V(c).
- Seismic anisotropy effectively reveals complex mantle flow dynamics.
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