A more reduced mantle beneath the lunar South Pole-Aitken basin.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40739093.
- Also identified by DOI 10.1038/s41467-025-62341-5 and PMC identifier 12310954.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The oxygen fugacity (fO<sub>2</sub>) of the lunar mantle is of pivotal significance in comprehending the formation and evolution of the Moon. However, the fO<sub>2</sub> of the lunar farside mantle remains unknown due to the lack of samples returned from the farside. Here, we determine the oxygen fugacity of 23 basaltic fragments from the Chang'e-6 (CE6) soil, the first farside sample collected from the South Pole-Aitken (SPA) basin. The spinel V oxybarometer and pyroxene Eu oxybarometer yield an average fO<sub>2</sub> of ΔIW -1.93 ± 0.58 (2σ), indicating a more reduced state compared to the nearside Apollo and Chang'e-5 (CE5) basalts, which have an average fO<sub>2</sub> of ΔIW -0.80 ± 0.64 (2σ). Such asymmetry in oxygen fugacity of the lunar mantle can be attributed to two processes: nearside mantle oxidation by a larger amount of Fe sinking into the core triggered by asymmetric crystallisation of the lunar magma ocean, and/or farside mantle reduction caused by S<sub>2</sub> and CO degassing during the SPA massive impact. Nevertheless, the reduced nature of the underlying mantle beneath the SPA basin reveals another aspect of lunar asymmetry.