Discriminating between Commercial and Residual Hydrocarbon Saturation Integrating Pre-stack Seismic and CSEM

We present an example from the Hoop area of the Barents Sea showing a sequential quantitative integration approach to integrate seismic and CSEM attributes using a rock physics framework, which allows us to discriminate between commercial and non-commercial (residual) hydrocarbon saturation. A dataset consisting of 2D GeoStreamer® seismic and towed streamer electromagnetic data that were acquired concurrently in 2015 by PGS provide the surface geophysical measurements used in this study. Two wells in the area: Wisting Central (7324/8-1) and Wisting Alternative (7324/7-1S) provide calibration for the rock physics modelling and the quantitative integrated analysis. In the first stage of the analysis, we invert pre-stack seismic and CSEM data separately for impedance and anisotropic resistivity respectively. We then apply the multi-attribute rotation scheme (MARS) to estimate rock properties from seismic data. This analysis verified that the seismic data alone cannot distinguish between commercial and non-commercial hydrocarbon saturations. Therefore, in the final stage of the analysis we invert the seismic and CSEM derived properties within a rock physics framework. The inclusion of the CSEM-derived resistivity information within the inversion approach allows for the separation of these two possible scenarios. Result show excellent correlation with known well outcomes.