Gyda is a 200MMstb field, located in the North Sea Central Trough, offshore Norway. The field was discovered in 1980, and first oil was produced in 1990. It is one of the deepest, hottest and poorest quality oilfields in the North Sea. The structurally complex field contains three different fluid types, and the crude is asphaltene rich. The shallow marine sandstone reservoir is gently dipping, wedge-shaped, with an oil column of 500m. The field receives no aquifer support and is being developed by waterflood. The connate water/injection water mix has a severe scaling tendency.
Development of the field is set against a background of tight cost control within the industry generally, and within the Operating company in particular. With six wells drilled per year, a current offtake rate of 70Mstbpd, and areas of the field showing early mature performance, the challenge is to maintain production whilst keeping costs low. The development is therefore managed by maintaining maximum flexibility in drilling locations, sequence and well use, by use of appropriate technology, and by the innovative use of conventional techniques to exploit the field's characteristics.
This paper describes: 1. reservoir complexity; 2. the technologies employed to meet the reservoir management challenges; 3. development philosophy; 4. field management history; and 5. value generation.