Three-dimensional geoelectrical surveys are widely used to map the subsurface in areas with complex geology. Field survey methods using offset pole–dipole and dipole–dipole arrays have been proposed large efficiently. However, it has found that negative apparent resistivity values sometimes encountered contrasts, particularly when offsets between current electrodes potential dipoles used. The v...

The present study explores the applicability and effectiveness of an optimization technique applied to electrical resistivity tomography data. procedure is based on Jacobian matrix, where most sensitive measurements are selected from a comprehensive data set enhance least resolvable parameters reconstructed model. Two existing inversion programs in two three dimensions modified incorporate this...

We present a heuristic, semiphenomenological model of the anomalous temperature (T) dependence of resistivity ρxx recently observed experimentally in the quasi-one-dimensional (Q1D) organic conductors of the (TMTSF)2X family in moderately strong magnetic fields. We suggest that a Q1D conductor behaves like an insulator (dρxx/dT < 0), when its effective dimensionality is one, and like a metal (d...

Low resistivity in argillaceous sandstone reservoirs may be attributed either to the effect of microporosity, or to specific effects due to clays and/or to conducting minerals. In the frame of a study on pore lining chlorite bearing sandstones, from different hydrocarbon reservoirs, measurements of cation exchange capacities and specific surface areas have been performed, on whole rocks as well...