Preparations for a PhD thesis on electric properties, as a function of pressure, temperature and water saturation, of porous reservoir- and cap-rocks saturated with gas water


This proposed PhD research project has not started yet. However, we have done preparatory studies for the research that will be undertaken from the second year by a PhD student. As a result, the research idea has been further refined and progress has been made in understanding the dynamic situation in the reservoir in course of injecting CO2 and capturing the signature of change through monitoring the electrical properties in association with the seismic properties.

From these studies it has been clear that the displacement of brine by CO2 will cause a change in the electrical resistivity and also changes in seismic velocities and amplitudes. Seismic and perhaps electrical measurements will be sensitive to the CO2 phase changes occurring at the critical point. Seismic properties may be affected by the quantity as well as the distribution of the phases. We conclude that in the lab experiments and theoretical studies to be carried out by the PhD student the sample behavior should be tested under reservoir conditions as a function of injected CO2, the phase of the CO2, and the brine salinity. This will give us a powerful tool to monitor pore pressure and the CO2 saturation.