Study on complex resistivity of artificial sandstone containing conductive mineral under high pressure

Due to the complex pore structure and non-single skeleton composition, natural rock samples are more difficult to study than artificial rock samples. The standard rock samples with different mineral content and volume content were artificially synthesized by using brass powder, pyrite sand, graphite powder, epoxy resin, etc. Complex resistivity measurements were taken to the samples by using AutoLab-1000 equipment under different formation pressure conditions. The complex resistivity and the parameters of zero frequency resistivity, polarizability, and time constant of the artificial sandstone standard were derived based on Debye decomposition model. Made a discussion on relationship between parameters of the model, including volume contents of conductive minerals, connectivity, formation pressure and other factors. Formation pressure and mineral composition have been found to have a large effect on polarizability. Research results are of great significance for understanding the electrical characteristics of artificial sandstone samples under high pressure.