Capillary-pressure curves and pore-throat size distribution by the combination of pressure-controlled mercury injection (PMI) and rate-controlled mercury injection (RMI). (A) Capillary-pressure curves by the comparison of PMI and RMI. (B) Pore size distribution by RMI. (C) Throat grading and overall throat size distribution by combination of PMI and RMI. kg = nitrogen permeability; ϕ = porosity.