A numerical model to estimate trapping conditions of fluid inclusions that homogenize by halite disappearance

Fluid inclusions (FI) that homogenize by halite disappearance are common in some geological environments, and interpretation of microthermometric data from these inclusions has been limited by the lack of a model describing the PVTX relationships over the complete range of PTX conditions found in nature. In this study, a system of equations has been developed that can be used to estimate salinity, pressure and density of FI that homogenize by halite disappearance. The salinity, pressure, density and dP/dT slope of the FI isochore are calculated as functions of liquid–vapor homogenization temperature (Th) and halite dissolution temperature (Tm). The equations are based on a numerical model describing the isochoric pressure–temperature trajectory followed by halite-saturated fluids during heating. The model is valid for Th and Tm from 100 to 600 °C, and for pressures along the liquid–vapor–halite curve to 300 MPa.