[SMP38-P03] Phase equilibrium relations in MgSiO3 – SiO2 system under high pressures
Keywords:enstatite chondrite, melting relation, magma ocean, mantle differentiation, high pressure experiments
In this context, understanding of melting relations over compositions between SiO2 and MgSiO3 is indispensable to clarify the mantle fractionation. It also relates to investigations of chemical compositions of the crust at early stage of the Earth. However, there have been very limited works on the effect of pressure in the MgSiO3–SiO2 system. In addition, available information regarding phase relations in the system is so far limited to 5 GPa (Dalton and Presnall, 1997). In this study, therefore, we would determine the melting relations at pressures 5 to 20 GPa, focusing on the compositions of MgO-xSiO2 (x = 0.8 to 1.2), covering silicate compositions of E-chondrite.
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