Simultaneous determination of dynamic permeability and streaming potential

To accurately model oil, gas, and water reservoirs reliable information of the rock properties is required. In this research steps are taken to develop more accurate measurement methods. We present laboratory measurements of the dynamic permeability on samples consisting of capillary tubes in combination with conductivity measurements. The dynamic permeability is a measure of the fluid flow response to an applied external oscillating pressure gradient, such as exists in seismic waves. The existing theoretical framework is investigated and validated to obtain a more profound insight in the electrokinetic coupling effects. The coupling describes the response of a fluid flow due to an external applied field, as has been demonstrated in recent field tests (Exxon Mobile, (Thomson, 1993)) where a high voltage source was used to induce a seismic response which was recorded by geophones. The coupling also describes the opposite effect where a pressure field is applied to create an induced electric field. From a small sensitivity study of the coupling factor, which was computed as function of a variety of its main parameters and the frequency, we can conclude that especially the salinity, permittivity and temperature are sensitive parameters.