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We devise a modified Carr-Purcell-Meiboom-Gill pulse sequence that allows us to probe the apparent internal field gradient distribution of a fluid-saturated porous medium as a function of the pore size. This distribution is displayed as a two-dimensional map with one axis being the field gradient, another axis being the T2 relaxation time reflecting different pore sizes, and the vertical amplitudes being proportional to the proton population. Such a scheme of two-dimensional representation for fluid-saturated porous media can also be used for the identification of pore fluids using the contrast of their diffusion coefficients.

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The static conductivity and dielectric constant of two-component periodic composite material are calculated using the Fourier expansion technique. The composite material consists of spheres that are arranged in simple, face-centered, or body-centered cubic lattices. The spheres may be isolated to yield high porosity or pore space, or they may intercept each other, leaving small pore space in between. The effective static conductivity and dielectric constant of such structures are computed theoretically when the pore space is filled with a material that has a conductivity or dielectric constant which differs from that of the matrix of the structure.

Laboratory measurements on the elastic moduli and the acoustic attenuation of fluid-saturated porous rock cylinders are frequently affected by the boundary conditions of the rock sample, i.e., whether the curved surface of the cylindrical sample is exposed to air or properly sealed. In this paper, the analytical solutions of these problems for the extensional, torsional, and flexural modes are derived, and several numerical examples are computed. It was found that there exists an ‘‘artificial’’ attenuation caused by the open-pore boundary condition, whose relaxation frequency, in the case of extensional mode, is directly proportional to the permeability of the rock and inversely proportional to the viscosity of the pore fluid and the square of the sample radius. This attenuation exists in both the extensional and the flexural modes but not in the torsional mode.