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Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion
D″ (Dee double prime), the lowermost layer of the Earth’s mantle, is the thermal boundary layer (TBL) of mantle convection immediately above the Earth’s liquid outer core. As the origin of upwelling of hot material and the destination of paleoslabs (downwelling cold slab remnants), D″ plays a major...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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American Association for the Advancement of Science
2017
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5710186/ https://www.ncbi.nlm.nih.gov/pubmed/29209659 http://dx.doi.org/10.1126/sciadv.1602700 |
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author | Borgeaud, Anselme F. E. Kawai, Kenji Konishi, Kensuke Geller, Robert J. |
author_facet | Borgeaud, Anselme F. E. Kawai, Kenji Konishi, Kensuke Geller, Robert J. |
author_sort | Borgeaud, Anselme F. E. |
collection | PubMed |
description | D″ (Dee double prime), the lowermost layer of the Earth’s mantle, is the thermal boundary layer (TBL) of mantle convection immediately above the Earth’s liquid outer core. As the origin of upwelling of hot material and the destination of paleoslabs (downwelling cold slab remnants), D″ plays a major role in the Earth’s evolution. D″ beneath Central America and the Caribbean is of particular geodynamical interest, because the paleo- and present Pacific plates have been subducting beneath the western margin of Pangaea since ~250 million years ago, which implies that paleoslabs could have reached the lowermost mantle. We conduct waveform inversion using a data set of ~7700 transverse component records to infer the detailed three-dimensional S-velocity structure in the lowermost 400 km of the mantle in the study region so that we can investigate how cold paleoslabs interact with the hot TBL above the core-mantle boundary (CMB). We can obtain high-resolution images because the lowermost mantle here is densely sampled by seismic waves due to the full deployment of the USArray broadband seismic stations during 2004–2015. We find two distinct strong high-velocity anomalies, which we interpret as paleoslabs, just above the CMB beneath Central America and Venezuela, respectively, surrounded by low-velocity regions. Strong low-velocity anomalies concentrated in the lowermost 100 km of the mantle suggest the existence of chemically distinct denser material connected to low-velocity anomalies in the lower mantle inferred by previous studies, suggesting that plate tectonics on the Earth’s surface might control the modality of convection in the lower mantle. |
format | Online Article Text |
id | pubmed-5710186 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | American Association for the Advancement of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-57101862017-12-05 Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion Borgeaud, Anselme F. E. Kawai, Kenji Konishi, Kensuke Geller, Robert J. Sci Adv Research Articles D″ (Dee double prime), the lowermost layer of the Earth’s mantle, is the thermal boundary layer (TBL) of mantle convection immediately above the Earth’s liquid outer core. As the origin of upwelling of hot material and the destination of paleoslabs (downwelling cold slab remnants), D″ plays a major role in the Earth’s evolution. D″ beneath Central America and the Caribbean is of particular geodynamical interest, because the paleo- and present Pacific plates have been subducting beneath the western margin of Pangaea since ~250 million years ago, which implies that paleoslabs could have reached the lowermost mantle. We conduct waveform inversion using a data set of ~7700 transverse component records to infer the detailed three-dimensional S-velocity structure in the lowermost 400 km of the mantle in the study region so that we can investigate how cold paleoslabs interact with the hot TBL above the core-mantle boundary (CMB). We can obtain high-resolution images because the lowermost mantle here is densely sampled by seismic waves due to the full deployment of the USArray broadband seismic stations during 2004–2015. We find two distinct strong high-velocity anomalies, which we interpret as paleoslabs, just above the CMB beneath Central America and Venezuela, respectively, surrounded by low-velocity regions. Strong low-velocity anomalies concentrated in the lowermost 100 km of the mantle suggest the existence of chemically distinct denser material connected to low-velocity anomalies in the lower mantle inferred by previous studies, suggesting that plate tectonics on the Earth’s surface might control the modality of convection in the lower mantle. American Association for the Advancement of Science 2017-11-29 /pmc/articles/PMC5710186/ /pubmed/29209659 http://dx.doi.org/10.1126/sciadv.1602700 Text en Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). http://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/4.0/) , which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. |
spellingShingle | Research Articles Borgeaud, Anselme F. E. Kawai, Kenji Konishi, Kensuke Geller, Robert J. Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion |
title | Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion |
title_full | Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion |
title_fullStr | Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion |
title_full_unstemmed | Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion |
title_short | Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion |
title_sort | imaging paleoslabs in the d″ layer beneath central america and the caribbean using seismic waveform inversion |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5710186/ https://www.ncbi.nlm.nih.gov/pubmed/29209659 http://dx.doi.org/10.1126/sciadv.1602700 |
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