Measurement of wettability of porous rock samples comprises nuclear magnetic resonance to calculate wettability index by combining values of water and oil saturated surfaces

摘要

The process of measuring the wettability of a porous rock sample in the presence of water and oil comprises determining the area of the surface wetted with water and the surface wetted with oil when the sample is saturated with both water and oil and calculating the wettability index by the combination of values obtained for the surfaces. The rock sample is placed inside a nuclear magnetic resonance apparatus, and the values are obtained from the bias of measurements over the relaxation time. The measurements can be made after centrifuging the rock sample or forced displacement of the fluids in a confinement module