Metal-silicate partitioning of tungsten at high pressure and temperature: Implications for equilibrium core formation in Earth

The mantle abundance of W could have been set by single-stage metal-silicate equilibration along the liquidus in a deep peridotite magma ocean at pressures from 20-50 GPa, and at oxygen fugacities consistent with the mantle's present iron budget (IW− 2 to − 2.5). Equilibration at higher pressure is viable if the core-forming metal contained a significant, but not unreasonable, abundance of carbon (∼ 2 wt.%). Recent continuous accretion models involving multi-stage metal-silicate equilibration in a deepening magma ocean with progressive oxidation of the silicate remain permissible given our new treatment of W partitioning data.