Effect of porosity, pore size and permeability on the complex relative permittivity of sandstone

The measurement of the frequency dependences of the complex relative permittivity (CRP) of fully or partially saturated with distilled water rocks with different petrophysical characteristics is carried out. NMR relaxometer is used to determine the rocks pore size and porosity. There are two relaxation areas on the frequency dependence of CRP at partial saturation. Simulation was carried out by the two relaxation model of the Cole-Cole. High-frequency relaxation is due to the polarization at the water-air interface. The low-frequency relaxation is due to the polarization at the water-mineral interface. The model parameters are related to the petrophysical characteristics of the rocks. Analysis of the NMR response showed that water redistribution between large and small pores occurs with a decrease of the water content. It also affects the dielectric spectra.