Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy
Abstract Subduction zones are a key link between the surface water cycle and the solid Earth, as the incoming plate carries pore water and hydrous minerals into the subsurface. However, water fluxes from surface to subsurface reservoirs over geologic time are highly uncertain because the volume of w...
| 出版年: | Geophysical Research Letters |
|---|---|
| 主要な著者: | , , |
| フォーマット: | 論文 |
| 言語: | 英語 |
| 出版事項: |
Wiley
2023-05-01
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| 主題: | |
| オンライン･アクセス: | https://doi.org/10.1029/2023GL103331 |
| _version_ | 1850070230356721664 |
|---|---|
| author | Hannah F. Mark Daniel Lizarralde Douglas A. Wiens |
| author_facet | Hannah F. Mark Daniel Lizarralde Douglas A. Wiens |
| author_sort | Hannah F. Mark |
| collection | DOAJ |
| container_title | Geophysical Research Letters |
| description | Abstract Subduction zones are a key link between the surface water cycle and the solid Earth, as the incoming plate carries pore water and hydrous minerals into the subsurface. However, water fluxes from surface to subsurface reservoirs over geologic time are highly uncertain because the volume of water carried in hydrous minerals in the slab mantle is poorly constrained. Estimates of slab mantle hydration based on seismic tomography assume bulk serpentinization, representing an upper bound on water volume. We measure azimuthal seismic anisotropy near the Marianas Trench, use spatial variations in anisotropy to constrain the extent and geometry of bend‐related faulting, and place a lower bound on slab mantle water content for the case where serpentinization is confined within fault zones. The seismic observations can be explained by a minimum of ∼0.85 wt% water in the slab mantle, compared to the upper bound of ∼2 wt% obtained from tomography. |
| format | Article |
| id | doaj-art-e968fdb5ce4e457499fff22df8a2ae81 |
| institution | Directory of Open Access Journals |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2023-05-01 |
| publisher | Wiley |
| record_format | Article |
| spelling | doaj-art-e968fdb5ce4e457499fff22df8a2ae812025-08-20T00:17:42ZengWileyGeophysical Research Letters0094-82761944-80072023-05-015010n/an/a10.1029/2023GL103331Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic AnisotropyHannah F. Mark0Daniel Lizarralde1Douglas A. Wiens2Woods Hole Oceanographic Institution Woods Hole MA USAWoods Hole Oceanographic Institution Woods Hole MA USAWashington University in St. Louis St Louis MO USAAbstract Subduction zones are a key link between the surface water cycle and the solid Earth, as the incoming plate carries pore water and hydrous minerals into the subsurface. However, water fluxes from surface to subsurface reservoirs over geologic time are highly uncertain because the volume of water carried in hydrous minerals in the slab mantle is poorly constrained. Estimates of slab mantle hydration based on seismic tomography assume bulk serpentinization, representing an upper bound on water volume. We measure azimuthal seismic anisotropy near the Marianas Trench, use spatial variations in anisotropy to constrain the extent and geometry of bend‐related faulting, and place a lower bound on slab mantle water content for the case where serpentinization is confined within fault zones. The seismic observations can be explained by a minimum of ∼0.85 wt% water in the slab mantle, compared to the upper bound of ∼2 wt% obtained from tomography.https://doi.org/10.1029/2023GL103331anisotropyserpentinizationsolid‐Earth water cyclesubductionMarianas Trench |
| spellingShingle | Hannah F. Mark Daniel Lizarralde Douglas A. Wiens Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy anisotropy serpentinization solid‐Earth water cycle subduction Marianas Trench |
| title | Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy |
| title_full | Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy |
| title_fullStr | Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy |
| title_full_unstemmed | Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy |
| title_short | Constraints on Bend‐Faulting and Mantle Hydration at the Marianas Trench From Seismic Anisotropy |
| title_sort | constraints on bend faulting and mantle hydration at the marianas trench from seismic anisotropy |
| topic | anisotropy serpentinization solid‐Earth water cycle subduction Marianas Trench |
| url | https://doi.org/10.1029/2023GL103331 |
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