气候变化领域集成服务门户(CCPortal): Heterogeneous accretion of Earth inferred from Mo-Ru isotope systematics

CCPortal

DOI	10.1016/j.epsl.2020.116065
	Heterogeneous accretion of Earth inferred from Mo-Ru isotope systematics
	Hopp T.; Budde G.; Kleine T.
发表日期	2020
ISSN	0012821X
卷号	534
英文摘要	The Mo and Ru isotopic compositions of meteorites and the bulk silicate Earth (BSE) hold important clues about the provenance of Earth's building material. Prior studies have argued that non-carbonaceous (NC) and carbonaceous (CC) meteorite groups together define a Mo-Ru ‘cosmic’ correlation, and that the BSE plots on the extension of this correlation. These observations were taken as evidence that the final 10–15% of Earth's accreted material derived from a homogeneous inner disk reservoir with an enstatite chondrite-like isotopic composition. Here, using new Mo and Ru isotopic data for previously uninvestigated meteorite groups, we show that the Mo-Ru correlation only exists for NC meteorites, and that both the BSE and CC meteorites fall off this Mo-Ru correlation. These observations indicate that the final stages of Earth's accretion were heterogeneous and consisted of a mixture of NC and CC materials. The Mo-Ru isotope systematics are best accounted for by either an NC heritage of the late veneer combined with a CC heritage of the Moon-forming giant impactor, or by mixed NC-CC compositions for both components. The involvement of CC bodies in the late-stage accretionary assemblage of Earth is consistent with chemical models for core-mantle differentiation, which argue for the addition of more oxidized and volatile-rich material toward the end of Earth's formation. As such, this study resolves the inconsistencies between homogeneous accretion models based on prior interpretations of the Mo-Ru systematics of meteorites and the chemical evidence for heterogeneous accretion of Earth. © 2020 The Author(s)
关键词	heterogeneous accretion isotope dichotomy late stage accretion nucleosynthetic isotope anomalies origin of volatiles siderophile elements
英文关键词	Binary alloys; Cosmology; Isotopes; Meteorites; Molybdenum; Silicates; heterogeneous accretion; Isotope anomalies; Late stage; origin of volatiles; Siderophile elements; Ruthenium; accretion; anomaly; chondrite; differentiation; enstatite; isotopic composition; meteorite; molybdenum; ruthenium; siderophile element
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202653
作者单位	Institut für Planetologie, University of Münster, Wilhelm-Klemm-Str. 10, Münster, 48149, Germany
推荐引用方式 GB/T 7714	Hopp T.,Budde G.,Kleine T.. Heterogeneous accretion of Earth inferred from Mo-Ru isotope systematics[J],2020,534.
APA	Hopp T.,Budde G.,&Kleine T..(2020).Heterogeneous accretion of Earth inferred from Mo-Ru isotope systematics.Earth and Planetary Science Letters,534.
MLA	Hopp T.,et al."Heterogeneous accretion of Earth inferred from Mo-Ru isotope systematics".Earth and Planetary Science Letters 534(2020).