A decoupling procedure for simulating fluid mixing, heat transfer and non-equilibrium redox chemical reactions in fluid-saturated porous rocks

Non-equilibrium redox chemical reactions of high orders are ubiquitous in fluid-saturated porous rocks within the crust of the Earth. They play a very important role in ore body formation and alteration closely associated with a mineralizing system. Since pore-fluid is a major carrier transporting chemical species from one part of the crust into another, the chemical process is coupled with the pore-fluid flow process in fluid-saturated porous rocks. In addition, if the rate of a chemical reaction is dependent on temperature, the chemical process is also coupled with the heat transfer process. When a pore-fluid carrying one type of chemical species meets with that carrying another type of chemical species, these two types of pore-fluids can mix together to allow the related chemical reaction to take place due to solute molecular diffusion/dispersion and advection. For these reasons, the resulting patterns of mineral dissolution, transportation, precipitation and rock alteration are a direct consequence of coupled processes between fluids mixing, heat transfer and chemical reactions in fluid-saturated porous rocks.