Melting Experiments on Fe-H and Implications for the Earth’s Core

Hydrogen is likely to be one of the important light elements incorporated in the Earth’s core. Melting phase diagram in hydrogen-bearing iron alloy has been an important missing piece to better understand the Earth’s core. Here we review recent melting experiments to determine the melting temperature, liquidus phase relation, and solid-liquid partition coefficient in the Fe-H binary and Fe-Si-H and Fe-O-H ternary systems up to the core pressure range by a combination of in-situ X-ray diffraction measurements and ex-situ textural and chemical characterizations on recovered samples. We also discuss the composition and temperature of the Earth’s core based on these experimental results and recent theoretical calculations.