Experimental determination of carbon isotope fractionation in theFe-C system under HPHT conditions.

在5和10 GPa和1200 - 2000 oC的温度范围内测定了石墨/金刚石和碳化铁熔体之间的平衡碳同位素分馏。结果表明，碳化铁熔体优先富集12 ^C，而不是13 ^C。我们提出，在早期地球的吸积和分异过程中，碳化铁熔体和石墨/金刚石之间的碳同位素随温度变化的分馏可能产生了一个“12^C富集核”，金属核中的碳和块状硅酸盐地球之间的碳同位素分布存在显着差异。

Equilibrium carbon isotope fractionation between graphite/diamond and iron carbide melt at 5 and 10 GPa and in the temperature range between 1200 and 2000 oC was determined. The results suggest that iron carbide melt will preferentially accumulate12^C rather than 13^C. We proposed that the temperature-dependent fractionation of carbon isotopes between iron carbide melt and graphite/diamond might have created a “12^C-enriched core” with a significant difference in the distribution of carbon isotopes between the carbon in the metallic core and bulk silicate Earth during the accretion and differentiation of early Earth.