Thermodynamic Properties of Oxide Compounds Occurring in Ca–Al-Rich Inclusions

Based on the analysis of experimental evidence on the high-temperature thermodynamic properties of oxide compounds occurring in Ca–Al-rich inclusions of chondrites, the enthalpies, entropies, and energies of mixing in molten oxide compounds were recommended. They can be used to calculate the activities of oxides and oxide compounds in melts of refractory inclusions in chondrites at temperatures of 1500–2700 K. The advantages and correctness of the developed approach to the obtaining of thermodynamic data were demonstrated by the agreement of calculated evolutionary changes during fractional evaporation of residual melts of Ca–Al-rich inclusions in chondrites and other meteoritic materials with experimental data.