The invention relates to the field of reservoir rock pore structure classification in the oil and gas
field development process, in particular to a
carbonate rock pore structure classification methodbased on an
overburden pressure seepage experiment, which comprises the following steps: preparing a
rock sample, and measuring the gas permeability of the
rock sample; after the
rock sample is saturated with simulated oil, performing a permeability-confining pressure relation determination experiment, and obtaining a permeability-confining
pressure curve; carrying out piecewise fitting on the permeability-confining
pressure curve to obtain a permeability-confining pressure fitting curve, and analyzing a parameter change rate of piecewise fitting; observing the
rock core, and preliminarily judging the pore
structure type according to the
rock core observation result; according to the difference of the change rates of the fitting parameters of different segments, classifying the pore
structure type of the
rock core by combining the rock core observation result and the theoretical analysis of the permeability-confining pressure fitting curve characteristics, and the pore structure
classification result of the classification method is closer to the real situation of the
carbonate reservoir.