Аннотация:The results of 354 "dry" quenching experiments (201 of them are high-pressure up to 23 kbar) characterizing the compositions of coexisting orthopyroxenes and melts were extracted from the INFOREX database. The orthopyroxene compositions were recalculated to 9 end-members: MgSiO3 (En – enstatite), FeSiO3 (Fs – ferrosilite), CaSiO3 (Wo – wollastonite), FeAlO3 (FeAl – ferral), AlAlO3 (AlAl – alal), Na0.5Al0.5SiO3 (Jd – jadeite), MgTiO3 (MgTi – magti), MnSiO3 (Rdn – rhodonite), CrSiO3 (CrPx – chrompyroxene).Thus, orthopyroxene liquidus thermobarometer representsa system of 9 equations, for example, for En: (1) where P is the pressure in kbar, T is the absolutetemperature, fO2 is the oxygen fugacity, Xi is the molar fraction of the i-th component of the melt, A, β, D, Ji are the coefficients at the corresponding variables, B is the constant, ail is the activity of the components in the melt according to the two-lattice model of silicate liquid of Nielsen with co-authors. In the temperature range from 1050 до 1500ºC, with a 95% probability, the calculated value of the liquidus temperature of orthopyroxene differs from the unknown true temperature by an amount not exceeding ± 5 degrees.