Depending on rock quality and material volume, multiple methods are available.
Centrifuge capillary pressure testing uses gravitational forces to measure the equilibrium saturation as a function of capillary pressure. Measurements are made on plug samples using the reservoir representative fluid system and can performed at overburden pressure, elevated temperature, and with real-time data acquisition through camera monitoring.
Porous plate capillary pressure measurements are made on plug samples using the fluid system that is representative of the reservoir and are performed at overburden pressure. Testing is typically performed in conjunction with electrical properties measurements.
Mercury Injection is a fast, cost-effective method and can be converted to reservoir fluid systems using assumed parameters. Suitable for samples ranging from cuttings to plugs.