Fluid compositional distribution in the crust estimated from isochemical potential modelling

Abstract

To understand the controls on the fluid compositional distribution in the crust, a thermodynamic model, which simulates the most stable distribution under pressure and temperature gradients, was established. NaCl solution was used as the representative of the crustal fluid. The model showed that the salinity increases with depth, and the salinity gradient is positively dependent on the temperature gradient. The calculation result was compared with natural salinity distribution of sedimentary fluids, and the calculated profiles are roughly consistent with natural data.