Geophysical Reservoir Monitoring: Where We Are!

Peter Engbers¹, Mohamed Al-Mughairy²*, Fahad Al-Kindy², Helmut Friesacher³, Nasser Al-Touqi², Saeed Al-Yarubi², and Issa Al-Quseimi^2
1BSP, Malaysia
²PDO
³Shell EPE, Aberdeen
*[email protected]

In our land environment, areal reservoir monitoring is not just 4-D seismic. It can best be achieved by a combination of various geophysical techniques integrated with well-based surveillance methods. These techniques include active seismic (surface and downhole), passive seismic (microseismic), surface deformation (GPS and satellite), electromagnetic induction, and gravity measurements. Enhanced oil recovery (EOR) projects are the prime candidates for the application of geophysical reservoir monitoring techniques because of the expected large acoustic effect and the large potential value. With EOR techniques becoming ever more important the use of reservoir monitoring techniques will increase significantly. Over the years several blockers for time-lapse (4D) seismic have been identified including: (1) limited changes of acoustic properties at seismic scale caused by low yearly production rates, (2) poor sweep, (3) stiff carbonate matrix, (4) dense surface infrastructure, (5) small areal scale of an injection pattern, (6) lack of suitable baseline surveys, and (6) difficult reservoirs. The critical success factor for those geophysical reservoir-monitoring projects is the full integration with the well-based monitoring data into the dynamic reservoir model. Involvement at the beginning of a field development program by geophysicists is essential for the success of such projects, as tailor-made solutions require adequate attention for project management, scoping, justification, technical design, tendering and contracting. Based on recent experiences a five-step approach evolved for geophysical reservoir monitoring projects. These include: (1) opportunity screening and selection of relevant technologies, (2) detailed design, (3) implementation, (4) data acquisition and processing, and (5) detailed integrated interpretation.

AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain