“…If CO 2 is to be safely and permanently stored by this method, two processes need to be understood: ''solubility trapping''-dissolution and long-term retention of CO 2 in saline groundwater; and ''mineral trapping''-reaction of CO 2 with non-carbonate minerals to form stable carbonates (cf., Gunter et al, 1997;Wawersik et al, 2001;Johnson et al, 2001Johnson et al, , 2002. However, a number of reactions may occur involving supercritical CO 2 , aquifer fluids and formation rocks, depending on the chemical composition of the fluid, pH, temperature, pressure and the mineralogy of the host rock (e.g., Gaus et al, 2005;Moore et al, 2005).…”