Special Core Analysis / Rock Properties

The objective of the mercury injection procedure is to determine mercury injection porosity, pore throat size distribution and generate air/mercury drainage phase

capillary pressure curves. Using conversion factors for contact angle and interfacial tension (IFT) further data can be derived, such as oil/brine capillary pressure, saturation as a function of height above free water level, Leverett J Function etc.  More comprehensive analyses are possible if required.

An example of a more specialised rock properties application:

Cap rock / seal evaluation

An understanding of capillary pressure behavior is vital to optimise reservoir characterisation and to accurately determine cap rock, intra-formational and fault sealing capacity.  Investigation of the sealing capacity and pore-throat aperture size distribution for seals and reservoir lithology is conducted via mercury porosimetry.

With regard to cap rocks and seals, entry pressure, displacement pressure, and threshold pressure are terms referring to critical points on the mercury injection curve.  The entry pressure is the point at which sufficient pressure is generated for the non-wetting phase to enter the pore space. The most important factor when evaluating seal potential is determining the pressure required to form a connected filament of non-wetting fluid through the pore space - the threshold / displacement pressure.

Permeability of seal / cap rock can also be investigated by combining mercury porosimetry with other techniques. The effectiveness of fault rock as seals can also be evaluated.

Chemical / Catalysts / Pharmaceuticals

Mercury porosimetry finds many applications in the chemical, material science, pharmaceutical industries and research laboratories. Porosity and pore size distribution provide vital information as to the effectiveness of many substances for their potential applications.  Solids and powders can be analysed plus materials in other forms such as films and tapes and coatings. Information can be produced on particle size characteristics and distributions.