Figure 4. The density profile of both CO₂ and N₂ at different pressures with varying pore sizes along z direction which is perpendicular to the clay surface.

(a) CO₂ at 1 MPa; (b) CO₂ at 10 MPa; (c) CO₂ at 30 MPa; (d) N₂ at 1 MPa; (e) N₂ at 10 MPa; (f) N₂ at 30 MPa.