Simulating the core‐mantle boundary: An experimental study of high‐pressure reactions between silicates and liquid iron

Experiments with the laser‐heated diamond cell show that (Mg,Fe)SiO 3 perovskite reacts chemically with liquid iron at pressures greater than 70 GPa and temperatures above 3700 K. X‐ray diffraction analyses of quenched samples demonstrate that the reaction products include SiO 2 stishovite and iron alloys (Fe,Mg) x O and Fe x Si y , at the interface between the Fe and silicate. Our results suggest that similar chemical reactions occur at the Earth's core‐mantle boundary, forming chemical heterogeneities composed of silicate‐rich and iron alloy‐rich regions in the D′ layer. This scenario is consistent with seismological observations.