Siderophile element constraints on the thermal history of the H chondrite parent body.

ABSTRACT: The abundances of highly siderophile elements (HSE: Re, Os, Ir, Ru, Pt, Pd), as well as ¹⁸⁷Re-¹⁸⁷Os and ¹⁸²Hf-¹⁸²W isotopic systematics were determined for separated metal, slightly magnetic, and nonmagnetic fractions from seven H4 to H6 ordinary chondrites. The HSE are too abundant in nonmagnetic fractions to reflect metal-silicate equilibration. The disequilibrium was likely a primary feature, as ¹⁸⁷Re-¹⁸⁷Os data indicate only minor open-system behavior of the HSE in the slightly and non-magnetic fractions. ¹⁸²Hf-¹⁸²W data for slightly magnetic and nonmagnetic fractions define precise isochrons for most meteorites that range from 5.2 ± 1.6 Ma to 15.2 ± 1.0 Ma after calcium aluminum inclusion (CAI) for

SUBMITTER: Archer GJ 

PROVIDER: S-EPMC6398954 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature