... Waxman-Smits and dual-water models of electrical conductivity in shaly sands account for the dual conductive pathways formed by pore brine and clay mineral exchange cations, while Archie?s equations describe the electrical conductivity behavior of shale-f Schwartz formation factor...

.... montmorillonite equivalent conductance clay exchange site Upstream Oil & Gas Waxman clay concentration shaly sand clay mineral log analysis exchange cation conductance conductivity cation counterion quadrature conductivity mobility well logging concentration binding energy Symposium...

... salinity. The excess conductivity is due to exchange cations concentrated in a diffuse layer near the clay surfaces. To account for the excess conductivity, the classical models rely on core or log determinations of Qv, the charge concentration of the exchange cations per unit pore volume. For log...

..., and in agreement with experimental data is the last one. well logging three-resistor model assumption heterogeneousmodel exchange cation particle conductivity Upstream Oil & Gas Waxman conduction path matrix log analysis shaly sand formation equation geometrical factor curvature...