ПетрологияПетрология0869-5903The Russian Academy of Sciences1158210.31857/S0869-5903272123-137Research ArticleA technique for calculating the enthalpy of silicate melt of arbitrary compositionBychkovD. A.<p>Geological Faculty</p>dmibychkov@gmail.comKoptev-DvornikovE. V.<p>Geological Faculty</p>ekoptev@geol.msu.ruMoscow State University020420192721231370104201901042019Copyright © 2019, Russian Academy of Sciences2019<p>The Kirchhoff equation was used to develop a method for calculating the enthalpy of silicate melt of any arbitrarily chosen composition with regard for the latent heat of fusion. To do this, the following two problems were solved: (a) the coefficients of the heat capacity equation of a silicate melt were revised and (b) the partial molar enthalpies of formation of melt components from elements at standard state were determined. The uncertainty in calculating the heat capacity of silicate melt at 95% significance level is no greater than 0.7 J mol1 K1. A weak but statistically significant temperature dependence of the heat capacity was determined. The enthalpies of melts calculated using the method are comparable with the values obtained by other techniques. The calculation error at 95% significance level is 2 relative %.</p>heat capacity of silicate meltenthalpy of silicate meltlatent heat of fusionтеплоемкость силикатного расплаваэнтальпия силикатного расплаваскрытая теплота плавления[Арискин А.А., Бармина Г.С. Моделирование фазовых равновесий при кристаллизации базальтовых магм. М.: МАИК «Наука/Интерпериодика», 2000. 363 с.][Богатиков О.А., Косарева Л.В., Шарков Е.В. Средние химические составы магматических горных пород: Справочник. М.: Недра, 1987. 152 с.][Наумов Г.Б., Рыженко Б.Н., Ходаковский И.Л. Справочник термодинамических величин (для геологов). М.: Атомиздат, 1971. 240 с.][Френкель М.Я. Тепловая и химическая динамика дифференциации базитовых магм. 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