How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior
Abstract Determining the fate of subducted oceanic crust is critical for understanding material cycling through Earth’s deep interior and sources of mantle heterogeneity. A key control on the distribution of subducted slabs over long timescales is the bridgmanite to post-perovskite phase transition...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2023-12-01
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| Series: | Communications Earth & Environment |
| Online Access: | https://doi.org/10.1038/s43247-023-01153-1 |
| _version_ | 1797376747657756672 |
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| author | Juliane Dannberg Kiran Chotalia Rene Gassmöller |
| author_facet | Juliane Dannberg Kiran Chotalia Rene Gassmöller |
| author_sort | Juliane Dannberg |
| collection | DOAJ |
| description | Abstract Determining the fate of subducted oceanic crust is critical for understanding material cycling through Earth’s deep interior and sources of mantle heterogeneity. A key control on the distribution of subducted slabs over long timescales is the bridgmanite to post-perovskite phase transition in the lowermost mantle, thought to cause rheological weakening. Using high-resolution computational models, we show that the ubiquitous presence of weak post-perovskite at the core-mantle boundary can facilitate or prevent the accumulation of basaltic oceanic crust, depending on the amount of weakening and the crustal thickness. Moderately weak post-perovskite ( ~ 10–100× weaker) facilitates segregation of crust from subducted slabs, increasing basalt accumulation in dense piles. Conversely, very weak post-perovskite (more than 100× weaker) promotes vigorous plumes that entrain more crustal material, decreasing basalt accumulation. Our results reconcile the contradicting conclusions of previous studies and provide insights into the accumulation of subducted crust in the lowermost mantle throughout Earth’s history. |
| first_indexed | 2024-03-08T19:43:11Z |
| format | Article |
| id | doaj.art-20dd66b0ede34981ae9bf065f467a5c5 |
| institution | Directory Open Access Journal |
| issn | 2662-4435 |
| language | English |
| last_indexed | 2024-03-08T19:43:11Z |
| publishDate | 2023-12-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Communications Earth & Environment |
| spelling | doaj.art-20dd66b0ede34981ae9bf065f467a5c52023-12-24T12:30:06ZengNature PortfolioCommunications Earth & Environment2662-44352023-12-014111110.1038/s43247-023-01153-1How lowermost mantle viscosity controls the chemical structure of Earth’s deep interiorJuliane Dannberg0Kiran Chotalia1Rene Gassmöller2Department of Geological Sciences, University of FloridaDepartment of Geological Sciences, University of FloridaDepartment of Geological Sciences, University of FloridaAbstract Determining the fate of subducted oceanic crust is critical for understanding material cycling through Earth’s deep interior and sources of mantle heterogeneity. A key control on the distribution of subducted slabs over long timescales is the bridgmanite to post-perovskite phase transition in the lowermost mantle, thought to cause rheological weakening. Using high-resolution computational models, we show that the ubiquitous presence of weak post-perovskite at the core-mantle boundary can facilitate or prevent the accumulation of basaltic oceanic crust, depending on the amount of weakening and the crustal thickness. Moderately weak post-perovskite ( ~ 10–100× weaker) facilitates segregation of crust from subducted slabs, increasing basalt accumulation in dense piles. Conversely, very weak post-perovskite (more than 100× weaker) promotes vigorous plumes that entrain more crustal material, decreasing basalt accumulation. Our results reconcile the contradicting conclusions of previous studies and provide insights into the accumulation of subducted crust in the lowermost mantle throughout Earth’s history.https://doi.org/10.1038/s43247-023-01153-1 |
| spellingShingle | Juliane Dannberg Kiran Chotalia Rene Gassmöller How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior Communications Earth & Environment |
| title | How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior |
| title_full | How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior |
| title_fullStr | How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior |
| title_full_unstemmed | How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior |
| title_short | How lowermost mantle viscosity controls the chemical structure of Earth’s deep interior |
| title_sort | how lowermost mantle viscosity controls the chemical structure of earth s deep interior |
| url | https://doi.org/10.1038/s43247-023-01153-1 |
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