Integrate Interpretation of EM and GeoStreamer Data to Improve Reservoir Characterization

September’s First Break carries a PGS paper which describes a geophysical reservoir characterization workflow that seeks to integrate elastic and electric attributes derived from the inversion of seismic and CSEM data to deliver an estimate of hydrocarbons in place, with a case study from the Barents Sea. 

The integration of complementary geophysical data is a technically challenging process, but overcoming these challenges can bring significant rewards. Broadband GeoStreamer® seismic and Towed Streamer EM derived properties, when integrated within a rock physics framework can deliver an estimation of the total hydrocarbon volume in place within a reservoir.

PGS employed the workflow on Skrugard (Johan Castberg) in the Barents Sea, demonstrating both the application of Towed Streamer EM data in frontier exploration and improving reservoir characterization for delineating fluid distribution.

While seismic data are particularly well suited to resolving structure and aiding understanding of rock properties, CSEM is sensitive to increased resistivity caused by the presence of hydrocarbons.

Recent drilling activity in the Barents Sea has highlighted the value of evaluating both seismic and resistivity data prior to exploration drilling. While a structure identified on seismic may look promising, the absence of a strong resistivity anomaly could mean a sub-commercial discovery.

The article demonstrates PGS’ capabilities for handling the challenge of complex background resistivities, imaging an embedded small thin reservoir, and discriminating reservoir fluids by combing the strengths of seismic and CSEM data through quantitative integration. The final product of the reservoir characterization process can produce an estimate of the total volume of hydrocarbon in place within a reservoir.

Further detail, including data examples, are available. To find out more please contact em@pgs.com

Reservoir characterization workflow for calculation of hydrocarbon volume estimate