Patent ID: 7131317

Claim:
A method for evaluating, with a same equipment, physical parameters including at least absolute permeability and porosity of rock fragments (F) taken in a porous medium, comprising a stage of immersing fragments contained in a containment chamber in a viscous fluid and of communicating the chamber containing the fragments with a source for injecting fluid under pressure so as to compress the gas trapped in the pores of the rock, a stage of measuring a physical quantity indicative of evolution of fluid absorption by the rock, modeling evolution of the physical quantity in the chamber, from initial values for the physical parameters of rock fragments (F), and a stage of iterative adjustment of values of the physical parameters of the rock fragments so as to obtain the best possible adjustment of the modeled evolution with the measured evolution of the physical quantity in the chamber, characterized in that: during the stage of immersion, in the viscous fluid, of the rock fragments contained in containment chamber, an injection pressure of the fluid or of a volume of fluid injected is measured, during the modeling stage, the evolution of the injection pressure of the fluid or of the volume of fluid injected is modeled from initial values selected a priori for absolute permeability (K) and the residual gas saturation and porosity (Φ), and during the adjustment stage, the value of the absolute permeability and of the porosity of the rock fragments is iteratively adjusted so as to obtain the best possible adjustment between the modelled pressure or injected volume evolution and the measured evolution of the pressure or of the volume injected in the chamber.