Özet: | This study investigates metal–silicate partitioning of neon (DNe) under the likely conditions of early Earth’s core formation: up to 16 GPa, ∼ 3000 K and an oxygen fugacity near IW-2 (2 log units below the Iron-Wüstite buffer). We find that the DNe coefficients range between 10−2 and 10−1. These partition coefficients are only one of the controlling factors of noble gas distributions within the early Earth: because, even if DHe and DNe are low (∼10−4), there may have been sufficient noble gases present in the mantle to supply a significant quantity of He and Ne to the core. Assuming gas-melt equilibrium of the molten proto-Earth with a nebular gas composition and concomitant metal-silicate differentiation, the core would have inherited and maintained throughout Earth’s history high 3He/4He ratios and low 3He/22Ne ratios (<0.6), making the core a potential source of primordial light noble gases in mantle plumes.
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