Potential applications of time-lapse marine CSEM to reservoir monitoring

Three different oil field production settings are identified where time-lapse marine CSEM could find reservoir monitoring application. One of these settings, low salinity water injection, is given particular attention in this work. We generate time-lapse CSEM amplitude data from a 3D fluid flow simulation model by converting the dynamic changes to resistivity changes, and then employing 1D–dipole forward modelling for an in-line acquisition geometry. We utilise a rock physics model that accounts for heterogeneity, and takes into consideration the time variations in the salinity and temperature profile to calculate the vertical resistivity for each simulator cell. The modelling uses as a guide a full field model for a North sea turbidite reservoir into which low salinity water is injected. Measuring the three amplitude components of the CSEM survey, it is concluded that time lapse CSEM has the potential to be used qualitatively to monitor the evolution of low salinity water injection.