A method is provided of determining saturation values corresponding to particular locations in a sample of a porous media, whereby such saturation values can be used in conjunction with corresponding capillary pressures to derive a capillary pressure curve. The method of the invention involves the use of nuclear magnetic resonance (NMR) imaging to obtain NMR intensity values corresponding to the locations of interest. Intensity is related to saturation by an appropriate function which is employed to determine the saturation values from the intensity values.