Total hydrocarbon volume in place: improved reservoir characterization from integration of towed-streamer EM and dual-sensor broadband seismic data

Understanding reservoir characteristics, such as porosity, water saturation, thickness and the lateral extension of the reservoir is key for the characterization of a reservoir. These parameters are important because they serve as veritable inputs for reservoir volumetric analysis, i.e. estimating the total volume of hydrocarbon in place. Seismic data provide high-resolution images of the subsurface structure, but attempts to map fluids from seismic data may be misleading due to the ambiguity between lithology-fluid and lithology effects. In contrast, CSEM (Controlled Source Electromagnetic) data constrains subsurface resistivity – a physical property that strongly correlates with the fluid content and saturation of hydrocarbon reservoirs. By carefully integrating complementary information from both types of data, the limitations of each method can be overcome and the strength of each exploited. Used together, they help to better understand the prospect and the reservoirs characteristics, ultimately de-risking exploration, and the further applications in field development and reservoir management.