Formation of the Lunar Primary Crust From a Long-Lived Slushy Magma Ocean.
Publication Date
2022-01-28Journal Title
Geophys Res Lett
ISSN
0094-8276
Publisher
American Geophysical Union (AGU)
Volume
49
Issue
2
Language
en
Type
Article
This Version
AO
VoR
Metadata
Show full item recordCitation
Michaut, C., & Neufeld, J. A. (2022). Formation of the Lunar Primary Crust From a Long-Lived Slushy Magma Ocean.. Geophys Res Lett, 49 (2) https://doi.org/10.1029/2021GL095408
Description
Funder: PNP/INSU/CNES
Abstract
Classical fractional crystallization scenarios of early lunar evolution suggest crustal formation by the flotation of light anorthite minerals from a liquid magma ocean. However, this model is challenged by the > 200 Myr age range of primitive ferroan anorthosites, their concordance with Mg-suite magmatism and by the compositional diversity observed in lunar anorthosites. Here, we propose a new model of slushy magma ocean crystallization in which crystals remain suspended in the lunar interior and crust formation only begins once a critical crystal content is reached. Thereafter crustal formation occurs by buoyant melt extraction and magmatism. The mixture viscosity strongly depends on temperature and solid fraction driving the development of a surface stagnant lid where enhanced solidification and buoyant ascent of melt lead to an anorthite-enriched crust. This model explains lunar anorthosites heterogeneity and suggests a crustal formation timescale of 100s Ma, reconciling anorthosite ages with an early age of the Moon.
Keywords
Planets, GEODESY AND GRAVITY, Lunar and planetary geodesy and gravity, PLANETARY SCIENCES: SOLID SURFACE PLANETS, Origin and evolution, Volcanism, Gravitational fields, Orbital and rotational dynamics, PLANETARY SCIENCES: FLUID PLANETS, PLANETARY SCIENCES: COMETS AND SMALL BODIES, PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS, Moon, TECTONOPHYSICS, Planetary volcanism, VOLCANOLOGY, Research Letter, magma ocean, lunar anorthosite, lunar crust, suspension
Relationships
Is supplemented by: https://doi.org/10.17863/CAM.73500
Sponsorship
EC, H2020, H2020 Priority Excellent Science, H2020 European Research Council (ERC) (101001689)
University of Lyon (ANR‐16‐IDEX‐0005)
Identifiers
grl63490, 2021gl095408
External DOI: https://doi.org/10.1029/2021GL095408
This record's URL: https://www.repository.cam.ac.uk/handle/1810/333030
Rights
Licence:
http://creativecommons.org/licenses/by-nc-nd/4.0/
Statistics
Total file downloads (since January 2020). For more information on metrics see the
IRUS guide.