Phase Relations Among End-Member Solids and a Binary Fluid Mixture

Phase equilibria calculation involving end-member solids and a binary fluid mixture is a logical extension of the topic handled in the last chapter. It is also geologically relevant, because the natural fluids are mixtures of a number of species including H₂O, CO₂, CH₄, etc. The computation of the mixed-volatile equilibria demands that the thermodynamic properties of the fluid mixtures be known. Accordingly, research work on the equations of state of the fluid mixtures of relevance to geochemistry has been a centerpiece of activity for about a decade (Holloway 1977; Jacobs and Kerrick 1981a,b; Kerrick and Jacobs 1981; Bowers and Helgeson 1983; Saxena and Fei 1988). The availability of these data has promoted our ability to predict mixed-volatile reactions with confidence.