Abstract
Using a 3-D mantle wedge flow field for a generic oblique subduction system, we calculate elastic tensors of mineral aggregates in the mantle wedge for A-, B-, C-, and E-type olivine crystal preferred orientations (CPO) and apply the calculated elastic tensor in the forward calculation of shear-wave splitting (SWS) through the mantle wedge. We find that the hexagonal approximation of the full tensor does not affect the SWS parameters (the fast direction and the delay time) significantly for all CPO types except that the delay time for C-type CPO becomes shorter. Additionally, we find that despite the 3-D mantle flow field that results from oblique subduction, the fast direction is margin-normal for A-, C- and E-type CPOs and margin-parallel for B-type CPO.
| Original language | English (US) |
|---|---|
| Article number | e2022GL100143 |
| Journal | Geophysical Research Letters |
| Volume | 49 |
| Issue number | 20 |
| DOIs | |
| State | Published - Oct 28 2022 |
Bibliographical note
Funding Information:We thank Maximiliano Bezada, Lars Hansen, and Zhao Zhu for discussions during the early phase of this research. We also thank Haemyeong Jung and Vadim Levin for thorough review, which improved the manuscript. This research was partially funded by NSF EAR‐1620604 to I.W.
Publisher Copyright:
© 2022 The Authors.
Keywords
- crystal preferred orientation
- mantle wedge flow
- mantle wedge seismic anisotropy
- oblique subduction
- shear wave splitting