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Melting relations in the Fe-rich portion of the system FeFeS at 30 kb pressure

R. Brett·P.M. Bell
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Abstract

The melting relations of FeFeS mixtures covering the composition range from Fe to Fe 67 S 33 have been determined at 30 kb pressure. The phase relations are similar to those at low pressure. The eutectic has a composition of Fe 72.9 S 27.1 and a temperature of 990°C. Solubility of S in Fe at elevated temperatures at 30 kb is of the same order of magnitude as at low pressure. Sulfur may have significantly lowered the melting point of iron in the upper mantle during the period of coalescence of metal prior to core formation in the primitive earth.

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R. Brett, P.M. Bell. 1969. Melting relations in the Fe-rich portion of the system FeFeS at 30 kb pressure. https://doi.org/10.1016/0012-821x(69)90119-8

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