POROELASTICITY - PARAMETERS REVIEWED

Deformation of porous rocks is investigated by experts of various fields. This is probably the reason why poroelastic parameters are neither uniformly defined nor represented by standard symbols in the literature, and why inconsistencies have appeared in some publications. This paper is intended to clarify the use of material properties in order to facilitate application of poroelasticity theory. The key parameters referenced from a selection of mostly recent papers are: drained and undrained moduli and Poisson ratios, grain and pore compressibilities, the coefficient of effective stress, the Skemption ratio (pore pressure parameter), storage parameters, the Darcy conductivity, and the hydraulic diffusivity. The latter parameter governs the diffusional behaviour of poroelastic processes, as has been demonstrated by Rice & Cleary (1976). Herein, their formulation of the theory is used. References to Biot's (1941) parameters, which may be more familiar to some researchers, are given for completeness. A variety of extensions of the theory that have been elaborated by others is outlined in the last section.