Chemical characteristics of iron meteorite parent bodies. (1st February 2022)

• Record Type: Journal Article
• Authors: Hilton, Connor D.; Ash, Richard D.; Walker, Richard J.
• Is Part Of: Geochimica et cosmochimica acta. Volume 318(2022)
• Page Start: 112
• Page End: 125
• Publication Date: 2022-02-01
• Subjects: Iron meteorite -- Highly siderophile elements -- Fractional crystallization -- Noncarbonaceous -- Carbonaceous; Geochemistry -- Periodicals; Meteorites -- Periodicals; Géochimie -- Périodiques; Météorites -- Périodiques; Geochemie; Astrochemie; Electronic journals; 551.905
• DOI: 10.1016/j.gca.2021.11.035
• Languages: English
• ISSNs: 0016-7037

Abstract

Abstract: The projected relative abundances of the highly siderophile elements (HSE; Re, Os, Ir, Ru, Pt, and Pd) for bulk parent bodies of 10 magmatic iron meteorite groups/grouplet (IC, IIAB, IIC, IID, IIF, IIIAB, IIIF, IVA, IVB, and South Byron Trio) are broadly similar and show no resolvable differences between noncarbonaceous (NC) and carbonaceous (CC) genetic heritage. The processes driving genetic isotopic heterogeneity in the early Solar System, therefore, evidently did not leave discernable chemical fingerprints with respect to HSE relative abundances on the bulk planetesimal scale. By contrast, the absolute abundances of HSE projected for parent body cores, which reflect core size, are more variable and, on average, higher in CC bodies compared to NC bodies. Overall, bulk core chemical compositions, as well as core size, are linked to the distribution of Fe within a parent body, which is controlled by its oxidation state. The CC parent bodies are constrained to have formed under heterogeneous oxidizing conditions which were, on average, more oxidizing than those of the NC environment.