Print this pagePSUsing Chemostratigraphy to Identify Reservoirs with Optimal Deliverability to Increase Gas Production from the Carboniferous (Pennsylvanian) of the United Kingdom Southern North Sea*
By
Georgina Doughty1, Tim Pearce2, and Duncan McLean3
Search and Discovery Article #40213 (2006)
Posted September 27, 2006
*Adapted from poster presentation at AAPG Annual Convention, Houston, Texas, April 9-12, 2006.
Click to view poster in PDF format (~4.3 mb).
1ConocoPhillips (UK) Limited, Aberdeen, United Kingdom ([email protected])
2Chemostrat Limited, Llanfyllin, United Kingdom
3Sheffield University, Sheffield, United Kingdom
Abstract
The application of the latest chemostratigraphic techniques (Pearce et al., 2006) has significantly advanced ConocoPhillips' understanding of the stratigraphic architecture of the UK Carboniferous Southern Gas Basin, in particular UK Quad 44- the heartland of the UK Carboniferous gas producing area. It has led to a focus on key reservoir intervals and ultimately contributed to exploration and development success.
Gas is currently produced from Westphalian A, B, and C/D reservoirs, which span approximately a 10-my. period and encompass a wide range of fluvial and lacustrine depositional environments. The latter record shifts in climate and sediment supply in a variety of high and low accommodation space settings. The resultant stratigraphic architecture is complex and predicting high net-to-gross, high deliverability section away from well control is a major challenge.
Decades of exploration and standard subsurface analysis have improved significantly the understanding of these varied depositional environments and therefore the prime reservoir intervals within them. More recently however, the identification and differentiation of very similar sand units through the application of chemostratigraphy has proved invaluable when used in conjunction with conventional palynology, well and seismic correlation predictive techniques. This integrated approach to reservoir prediction has enabled optimal well placement of both exploration and development wells, resulting in higher deliverability wells and efficient reservoir drainage. A case study, “exploration to development of the Munro field Block 44/17b,” is used to illustrate the high impact of the new chemostratigraphic scheme, which has improved reservoir prediction and allowed exploration to focus on the highest deliverability reservoirs.
Selected Figures
Reference
Pearce, Timothy J., Duncan McLean, John H. Martin, Georgina Doughty, and David Wray, 2006, Chemostratigraphy and its role in a multi-disciplinary stratigraphic approach to the exploration and development of Upper Carboniferous (Pennsylvanian) gas ields in Southern North Sea: Search and Discovery Article # (AAPG Annual Convention abstracts) (http://www.searchanddiscovery.net/documents/2006/06088houston_abs/abstracts/pearce.htm).