NMR MEASUREMENTS AND NUMERICAL-SIMULATION OF FLUID TRANSPORT IN POROUS SOLIDS

Pulsed magnetic field gradient stimulated echo NMR measurements are pe rformed for diffusion and flow of an aqueous phase both within a sampl e of packed spherical beads and within a 25% porosity Fontainebleau sa ndstone. The stimulated echo dependence on the gradient pulse area q i s used to derive the displacement probability distributions P-Delta(X) for fixed observation times Delta. The shape of P-Delta(X) as a funct ion of Delta is simulated for computer-generated porous media, and a g ood agreement is obtained between the experimental NMR data and the si mulations.