title: Effects of microgeometry on the permittivity of impregnated porous media.
abstract: We propose a new approximative relation for the low-frequency dielectric permittivity of liquid-filled porous materials. In this formulation, effects of microgeometry are included through the so-called [Formula: see text] parameter. Our measurements on salt-water-impregnated artificial sandstones support the new relation. We also show that the high permittivities at low frequencies reported earlier for brine-impregnated sintered glass spheres (Nøst  et al 1992  Phys. Scr. T  44 67) may be due to effects at the solid - liquid interface in the `bulk' porous material. The latter results are also in agreement with our proposed relation.
authors.affiliation: Physics Department, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Nettelblad
authors.forename: G A
authors.initials: GA
authors.lastname: Niklasson