To systematically investigate seismic azimuthal anisotropy in the Sumatra subduction zone and probe mantle dynamics associated with the subduction of the Australian Plate beneath the Sunda Plate, a total of 169 pairs of teleseismic XKS (including PKS, SKKS, SKS) and 115 pairs of local
In approximately one fourth of worldwide subduction zones, seismic observations indicate a rotation from trench‐normal to trench‐parallel fast axis orientations in the mantle wedge. To interpret this observation we predict the evolution of crystal lattice preferred orientation in mantle wedge material as a function of the amount of water by using a model of polycrystal deformation (D‐Rex) coupled with an analytical corner flow. The resulting seismic signature is obtained from synthetic seismic wave propagation through this mantle wedge. We identify that progressive hydration produces the rotation of fast axis orientations and can generate between the two zones of trench‐parallel and trench‐normal fast axis orientations a morph zone with very small anisotropy and a related decrease in
- NSF-PAR ID:
- 10454987
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 45
- Issue:
- 24
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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