Geology and hydrothermal evolution of the Baituyingzi porphyry Mo (Cu) deposit, eastern Inner Mongolia, NE China: Implications for Mo and Cu precipitation mechanisms in CO2-rich fluids

Therefore, fluid evolution at Baituyingzi was characterized by relatively continuous, system-scale cooling along an ascent path gradually straddling the vapor-brine, vapor-liquid, and water-CO2 surface in the vapor-dominated H2OCO2NaCl fluid system, whereas the subtle temporal change in P-T-redox conditions and acid balance of the evolutionary paths of the magmatic fluid may be responsible for Cu and Mo separation at the Baituyingzi CO2-rich systems. Additionally, water-CO2 immiscibility seems to be an additional important mechanism that complicates Mo precipitation in CO2-rich systems.