Determination of scanning loops of capillary pressure and relative permeability curves and wettability distribution of rock samples

Abstract

A primary drainage process, a core aging process, a spontaneous water imbibition process, a forced water imbibition process, a spontaneous hydrocarbon imbibition process, and a secondary drainage process is conducted on a rock sample. For each of the primary drainage process, the spontaneous water imbibition process, the forced water imbibition process, the spontaneous hydrocarbon imbibition process, and the secondary drainage process, a pressure distribution and a fluid saturation distribution are measured across multiple locations along the rock sample. For each of the locations, the pressure distribution and the fluid saturation distribution are combined to produce a capillary pressure bounding curve and scanning loop for the rock sample, and a relative permeability bounding curve and scanning loop are determined at least based on the measured fluid saturation and pressure distributions at the respective location. A wettability distribution along the rock sample is determined based on the bounding curves and scanning loops.