Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry
Abstract The evolution of the planetary interior during plate tectonics is controlled by slow convection within the mantle. Global-scale geochemical differences across the upper mantle are known, but how they are preserved during convection has not been adequately explained. We demonstrate that the...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2017-05-01
|
| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-017-01816-y |
| _version_ | 1819127345876828160 |
|---|---|
| author | T. L. Barry J. H. Davies M. Wolstencroft I. L. Millar Z. Zhao P. Jian I. Safonova M. Price |
| author_facet | T. L. Barry J. H. Davies M. Wolstencroft I. L. Millar Z. Zhao P. Jian I. Safonova M. Price |
| author_sort | T. L. Barry |
| collection | DOAJ |
| description | Abstract The evolution of the planetary interior during plate tectonics is controlled by slow convection within the mantle. Global-scale geochemical differences across the upper mantle are known, but how they are preserved during convection has not been adequately explained. We demonstrate that the geographic patterns of chemical variations around the Earth’s mantle endure as a direct result of whole-mantle convection within largely isolated cells defined by subducting plates. New 3D spherical numerical models embedded with the latest geological paleo-tectonic reconstructions and ground-truthed with new Hf-Nd isotope data, suggest that uppermost mantle at one location (e.g. under Indian Ocean) circulates down to the core-mantle boundary (CMB), but returns within ≥100 Myrs via large-scale convection to its approximate starting location. Modelled tracers pool at the CMB but do not disperse ubiquitously around it. Similarly, mantle beneath the Pacific does not spread to surrounding regions of the planet. The models fit global patterns of isotope data and may explain features such as the DUPAL anomaly and long-standing differences between Indian and Pacific Ocean crust. Indeed, the geochemical data suggests this mode of convection could have influenced the evolution of mantle composition since 550 Ma and potentially since the onset of plate tectonics. |
| first_indexed | 2024-12-22T08:10:28Z |
| format | Article |
| id | doaj.art-8a936aaf38c44e769d50a672e6ff9266 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-22T08:10:28Z |
| publishDate | 2017-05-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-8a936aaf38c44e769d50a672e6ff92662022-12-21T18:33:02ZengNature PortfolioScientific Reports2045-23222017-05-01711910.1038/s41598-017-01816-yWhole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistryT. L. Barry0J. H. Davies1M. Wolstencroft2I. L. Millar3Z. Zhao4P. Jian5I. Safonova6M. Price7Department of Geology, University of LeicesterSchool of Earth and Ocean Sciences, Cardiff UniversityJBA Risk Management, Broughton HallNERC Isotope Geosciences Laboratory, British Geological Survey, KeyworthSchool of Earth Science and Resources, China University of GeosciencesBeijing SHRIMP Centre, Institute of Geology, Chinese Academy of Geological SciencesSobolev Institute of Geology and Mineralogy SB RASSchool of Earth and Ocean Sciences, Cardiff UniversityAbstract The evolution of the planetary interior during plate tectonics is controlled by slow convection within the mantle. Global-scale geochemical differences across the upper mantle are known, but how they are preserved during convection has not been adequately explained. We demonstrate that the geographic patterns of chemical variations around the Earth’s mantle endure as a direct result of whole-mantle convection within largely isolated cells defined by subducting plates. New 3D spherical numerical models embedded with the latest geological paleo-tectonic reconstructions and ground-truthed with new Hf-Nd isotope data, suggest that uppermost mantle at one location (e.g. under Indian Ocean) circulates down to the core-mantle boundary (CMB), but returns within ≥100 Myrs via large-scale convection to its approximate starting location. Modelled tracers pool at the CMB but do not disperse ubiquitously around it. Similarly, mantle beneath the Pacific does not spread to surrounding regions of the planet. The models fit global patterns of isotope data and may explain features such as the DUPAL anomaly and long-standing differences between Indian and Pacific Ocean crust. Indeed, the geochemical data suggests this mode of convection could have influenced the evolution of mantle composition since 550 Ma and potentially since the onset of plate tectonics.https://doi.org/10.1038/s41598-017-01816-y |
| spellingShingle | T. L. Barry J. H. Davies M. Wolstencroft I. L. Millar Z. Zhao P. Jian I. Safonova M. Price Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry Scientific Reports |
| title | Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry |
| title_full | Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry |
| title_fullStr | Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry |
| title_full_unstemmed | Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry |
| title_short | Whole-mantle convection with tectonic plates preserves long-term global patterns of upper mantle geochemistry |
| title_sort | whole mantle convection with tectonic plates preserves long term global patterns of upper mantle geochemistry |
| url | https://doi.org/10.1038/s41598-017-01816-y |
| work_keys_str_mv | AT tlbarry wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT jhdavies wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT mwolstencroft wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT ilmillar wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT zzhao wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT pjian wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT isafonova wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry AT mprice wholemantleconvectionwithtectonicplatespreserveslongtermglobalpatternsofuppermantlegeochemistry |