Date:     Tuesday 1st March, 2011.
Venue:   Valpark Chinese Restaurant
Time:     11:30am - 1pm

Reservoir Distribution and Prediction- Linked Deltaic, Shelf and Slope Depositional Systems - Dr. Grant Wach

Linked depositional systems on active and passive margins provide a variety of opportunities for accumulation of reservoir quality sands, but preservation and continuity of these deposits can be problematic. Continuity of reservoir is subject to depositional and stratigraphic control, in addition to the inherent structural complexity of the margin, coupled with syntectonic activity.

 Studies of petroleum systems formed in depositional environments ranging from deltaic to deepwater fans, including examples from offshore West Africa, the Gulf of Mexico, South Africa,  the Caribbean, South America and offshore Atlantic Canada, will illustrate reservoir complexities both on a basin scale, and at the field scale. At the basin scale, seismic and well log data sets are used to discern the presence of reservoir quality rocks and to develop a stratigraphic framework to use for predicting reservoir where little data exists. At the field scale the complex heterogeneities, i.e. baffles and barriers that may limit oil and gas production (reservoir performance) will be illustrated.

 We need to understand the stratigraphy and depositional environments within a basin before exploration begins. This provides the framework for future development work. To maximize resource recovery, we must model reservoirs with greater accuracy. This can only be achieved through multi-disciplinary, collaborative research particularly with our colleagues in engineering.

 Our preferred approach is to integrate analogous outcrop and subsurface data with iterative studies that incorporate regional basin scale parameters (e.g. plate movements and provenance) down to the microprobe (e.g. complex mineralogy and effective porosity).  Shallow seismic analogs are used for understanding and characterizing deeper reservoirs that are poorly imaged in the seismic data. Seismic data from the shallow time interval has better resolution to provide the critical stratigraphic and architectural detail. Integration with analog outcrop studies increases our “resolution” of these deeper targets. Data and interpretations from outcrop studies provide a sense of scale for reservoir systems where only sparse data are available.

Grant Wach is Professor of Petroleum Geoscience in the Department of Earth Sciences at Dalhousie University and has been a Visiting Professor for the Petroleum Geoscience Programme at U.W.I. Prior to his Dalhousie appointment in 2002 he was Geoscience Research Associate at Texaco Upstream Technology (now Chevron) in Houston, Texas. At Texaco he was a specialist in nonmarine and deepwater depositional systems, reservoir characterization, sequence stratigraphy, clastic sedimentology and core description for business units, operating affiliates and partners worldwide. He has considerable exploration and commercialization experience in West Africa, the Far East, the Americas and Western Europe. 

While at Texaco he had the pleasure of working on several studies with Petrotrin and Trinmar on the Phase II Exploration Study under the direction of Winston Ali; and the Soldado Extension Study (S-745). Off the East Coast Marine Area he was worked with BG on the Dolphin and Starfish fields. He is an active member of the Geological Society of Trinidad and Tobago giving lectures and leading field seminars.

 Dr. Wach began his petroleum industry career in 1979 with Syncrude in the oilsands of northeastern Alberta. This provided a unique opportunity to spend several years working, literally, inside a complex oil reservoir. His undergraduate degree is from the University of Western Ontario, M.Sc. from the University of South Carolina and D.Phil. from the University of Oxford. In the past he has also worked for the Ontario Geological Survey and Exxon Production Research Company (now ExxonMobil). He has numerous articles, abstracts and technical reports in several areas of sedimentology and stratigraphy. He has lectured and led field seminars at several universities and for industry worldwide.