Long-term reduced lunar mantle revealed by Chang'e-5 basalt.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39333517.
- Also identified by DOI 10.1038/s41467-024-52710-x and PMC identifier 11437062.
- Licence recorded as CC BY-NC-ND.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The redox state of a planetary mantle affects its thermal evolution. The redox evolution of lunar mantle, however, remains unclear due to limited oxygen fugacity (fO<sub>2</sub>) constraints from young lunar samples. Here, we report vanadium (V) oxybarometers on olivine and spinel conducted on 27 Chang'e-5 basalt fragments from 2.0 billion years ago. These fragments yield an average fO<sub>2</sub> of ΔIW -0.84 ± 0.65 (2σ), which closely aligns with the Apollo samples from 3.6-3.0 billion years ago. This temporal uniformity indicates the lunar mantle remained reduced. This observation reveals that the processes responsible for oxidizing mantles of Earth and Mars either did not occur or had negligible oxidizing effects on the Moon. The long-term reduced mantle may lead to a distinctive volatile degassing pathway for the Moon. It could also make the lunar mantle more difficult to melt, preventing internal heat dissipation and consequently resulting in a slow cooling rate.