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Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities
Seismic heterogeneities detected in the lower mantle were proposed to be related to subducted oceanic crust. However, the velocity and density of subducted oceanic crust at lower-mantle conditions remain unknown. Here, we report ab initio results for the elastic properties of calcium ferrite‐type ph...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6946644/ https://www.ncbi.nlm.nih.gov/pubmed/31911578 http://dx.doi.org/10.1038/s41467-019-13720-2 |
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author | Wang, Wenzhong Xu, Yinhan Sun, Daoyuan Ni, Sidao Wentzcovitch, Renata Wu, Zhongqing |
author_facet | Wang, Wenzhong Xu, Yinhan Sun, Daoyuan Ni, Sidao Wentzcovitch, Renata Wu, Zhongqing |
author_sort | Wang, Wenzhong |
collection | PubMed |
description | Seismic heterogeneities detected in the lower mantle were proposed to be related to subducted oceanic crust. However, the velocity and density of subducted oceanic crust at lower-mantle conditions remain unknown. Here, we report ab initio results for the elastic properties of calcium ferrite‐type phases and determine the velocities and density of oceanic crust along different mantle geotherms. We find that the subducted oceanic crust shows a large negative shear velocity anomaly at the phase boundary between stishovite and CaCl(2)-type silica, which is highly consistent with the feature of mid-mantle scatterers. After this phase transition in silica, subducted oceanic crust will be visible as high-velocity heterogeneities as imaged by seismic tomography. This study suggests that the presence of subducted oceanic crust could provide good explanations for some lower-mantle seismic heterogeneities with different length scales except large low shear velocity provinces (LLSVPs). |
format | Online Article Text |
id | pubmed-6946644 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-69466442020-01-09 Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities Wang, Wenzhong Xu, Yinhan Sun, Daoyuan Ni, Sidao Wentzcovitch, Renata Wu, Zhongqing Nat Commun Article Seismic heterogeneities detected in the lower mantle were proposed to be related to subducted oceanic crust. However, the velocity and density of subducted oceanic crust at lower-mantle conditions remain unknown. Here, we report ab initio results for the elastic properties of calcium ferrite‐type phases and determine the velocities and density of oceanic crust along different mantle geotherms. We find that the subducted oceanic crust shows a large negative shear velocity anomaly at the phase boundary between stishovite and CaCl(2)-type silica, which is highly consistent with the feature of mid-mantle scatterers. After this phase transition in silica, subducted oceanic crust will be visible as high-velocity heterogeneities as imaged by seismic tomography. This study suggests that the presence of subducted oceanic crust could provide good explanations for some lower-mantle seismic heterogeneities with different length scales except large low shear velocity provinces (LLSVPs). Nature Publishing Group UK 2020-01-07 /pmc/articles/PMC6946644/ /pubmed/31911578 http://dx.doi.org/10.1038/s41467-019-13720-2 Text en © The Author(s) 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Article Wang, Wenzhong Xu, Yinhan Sun, Daoyuan Ni, Sidao Wentzcovitch, Renata Wu, Zhongqing Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
title | Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
title_full | Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
title_fullStr | Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
title_full_unstemmed | Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
title_short | Velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
title_sort | velocity and density characteristics of subducted oceanic crust and the origin of lower-mantle heterogeneities |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6946644/ https://www.ncbi.nlm.nih.gov/pubmed/31911578 http://dx.doi.org/10.1038/s41467-019-13720-2 |
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