Water Vapour Sorption by Shales

Porosity and pore structure are very important parameters in many geological and engineering applications. With respect to shales or mudrocks, these properties are essential in the assessment of multiphase transport, geomechanical behaviour and storage/sealing capacity. A multitude of methods are currently in use for determination of porosity, each of which has advantages and pitfalls. Though porosity is theoretically an intrinsic property of a rock, different techniques often yield substantially different results. This is above all the case for shales, of which the pore structure comprises substantial micro-( 50 nm) porosity. Particularly the lower range of pore sizes makes it hard to adequately characterize porosity by routine methods, such as those used for conventional reservoir rocks (e.g. petrography, computer tomography or mercury intrusion porosimetry).