Davies, C.J. orcid.org/0000-0002-1074-3815, Pommier, A., Greenwood, S. et al. (1 more author) (2024) Thermal and magnetic evolution of Mercury with a layered Fe-Si(-S) core. Earth and Planetary Science Letters, 641. 118812. ISSN 0012-821X
Abstract
Elucidating the structure and composition of Mercury is important for understanding its interior dynamics and evolution. The planet is characterised by unusual chemical characteristics and a weak magnetic field generated in a large metallic core, and its early evolution was also marked by the presence of a magnetic field, widespread volcanism and global contraction. Here we develop a parameterised model of coupled core-mantle thermal and magnetic evolution considering a layered Fe-Si(-S) core structure with chemical and physical properties of the mantle and the core based on previous laboratory studies. We seek successful solutions that are consistent with observations of Mercury's long-lived dynamo, total global contraction, present-day crustal thickness, and present-day interior structure. Successful solutions have a mantle reference viscosity Pa s (corresponding to a present-day bulk mantle viscosity Pa s), a silicon concentration in the core >13 wt%, a present inner core radius of km and a thermally stable layer ∼ km thick below the core-mantle boundary. Our results show that if present, a molten FeS layer atop the core has minimal effect on Mercury's long-term thermal and magnetic evolution. Predictions from our models can be tested with upcoming Bepi-Colombo observations.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2024 The Author(s). This is an open access article under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited. |
Keywords: | Mercury, Thermal history, Core evolution, Magnetic field, FeS layer |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst of Geophysics and Tectonics (IGT) (Leeds) |
Funding Information: | Funder Grant number NERC (Natural Environment Research Council) NE/V010867/1 NERC (Natural Environment Research Council) NE/T003855/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 04 Jun 2024 15:00 |
Last Modified: | 11 Sep 2024 14:58 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.epsl.2024.118812 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:213041 |