Chemical reaction between silicate and molten iron at bottom of magma ocean and core-mantle boundary

Abstract

Interaction between the lower mantle and core is essential for understanding the composition of the core. Thermodynamic parameters of chemical reaction between silicate and molten iron are calculated from data set of experiments at high pressure and high temperature condition [Sakai et al. (2006), Takafuji et al. (2004, 2005), Kawazoe and Ohtani (2006)]. Pressure and temperature dependency of solubility of silicon and oxygen indicates that the solubility at 60 GPa and 3500 K can account for the 10% core density deficit. This pressure and temperature condition corresponds to the base of the magma ocean in the early earth.