carbon dioxide is set at 700 kg m 3 at 15 mpa with a compressibility and viscosity of 3 u00d7 10 u2212 8 pa u2212 1 and 6 u00d7 10 u2212 5 pa s respectively the resident brine and the injected water are assigned a density of 1100 kg m 3 and a viscosity of 6 u00d7 10 u2212 4 pa s compressibility effect for the aqueous phase is negligible and is therefore ignored during injection of carbon dioxide and subsequent counter imbibition residual saturations of brine and carbon dioxide respectively are left behind for residual water saturation i e the maximum fraction of the pore volume occupied by the trapped wetting phase a value of 0 075 is assigned for the maximum residual carbon dioxide saturation a value of 0 3 is used before commencement of injection the pressure at the top of layer 2 is 13 mpa i e this is the initial reservoir pressure at the top of layers of interest in the illustration carbon dioxide injection is assumed to occur through the bottom ten meters of the thirty meter layer 0 at a fixed pressure with the formation described above with reference to fig1 and with the formation simulation values as described above simulations were run for three different scenarios in a first scenario example 0 it was assumed that carbon dioxide was.