Exciting new insights into the moon's geological history have emerged from the Chang'e-5 mission. Scientists from the Chinese mainland, led by Wang Shuijiong of the China University of Geosciences in Beijing, have analyzed lunar samples that challenge the classic two-stage model of the moon's crust formation.
The traditional magma ocean model posits that the moon's crust developed in two distinct phases: the initial formation of a primitive crust from plagioclase during the cooling of the magma ocean, followed by a secondary stage involving mantle overturn and the creation of magnesian-suite rocks. However, recent findings suggest a more continuous process.
Through their joint study, the research team discovered a melt body similar to magnesian-suite rocks within an anorthosite fragment from the Chang'e-5 lunar regolith. Published in Communications Earth & Environment, the study provides compelling evidence that lunar anorthosite and the parent magma of magnesian-suite rocks formed simultaneously.
Geochemical and thermodynamic simulations indicate that the parent magma originated from the lunar upper mantle. This points to a continuous crust formation process, where gravitational instabilities during the cooling of the lunar magma ocean caused small-scale, in-situ overturns in the upper mantle, followed by larger-scale mantle overturns and decompression melting of the lower mantle.
These discoveries offer a new perspective on the moon's geological evolution, linking the formation of the primitive crust with the reformation of the secondary crust in a seamless process. The Chang'e-5 mission, which successfully returned 1,731 grams of lunar samples to Earth on December 17, 2020, continues to provide invaluable data that deepens our understanding of the moon's history.
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Chang'e-5 lunar sample reveals early moon crust formation process
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