Statfjord turns 40Statfjord A platform top view. Source: Harald Pettersen, Equinor

Statfjord turns 40

Statfjord A was one of the very first fields Equinor operated, after taking over from Mobil in 1987. Production began on November 24, 1979.

Statfjord is a field in the Tampen area in the northern part of the North Sea, on the border between the Norwegian and UK sectors. The Norwegian share of the field is 85.47%.

Statfjord was discovered in 1974, and since the field has produced 5.1 billion barrels of oil equivalent. Statfjord’s gross revenues are well over NOK 1675 billion during those 40 years of production.

The field has been developed with three fully integrated concrete facilities: Statfjord A, Statfjord B and Statfjord C. Statfjord A, centrally located on the field, came on stream in 1979. Statfjord B, in the southern part of the field, in 1982, and Statfjord C, in the northern part, in 1985. The satellite fields Statfjord Øst, Statfjord Nord and Sygna have a dedicated inlet separator on Statfjord C.

Statfjord and nearby fields with subsea templates. Source: Artist’s impression, Equinor (Statfjord Industrial Heritage)

Statfjord produces oil and associated gas from Jurassic sandstone in the Brent and Statfjord Groups, and in the Cook Formation. The Brent and Statfjord Groups have excellent reservoir quality. The reservoirs lie at a depth of 2,500-3,000 m (6×24 km size) in a large fault block tilted towards the west, and in several smaller blocks along the eastern flank.

Simplified reservoir model at Statfjord. Source: Equinor (Statfjord Industrial Heritage)

Thanks to active subsurface work, efficient drilling and well operations, and well operated installations Statfjord successfully increases production for the fourth consecutive year in 2019.

451 wells have been drilled so far on the field.

Statfjord is still producing oil. However, the most important decision after the turn of the millennium was made in 2005. Through the Statfjord Late Life project, the field was converted from an oil field to a gas field by reducing the reservoir pressure.

NOK 23 billion was invested, and production was maintained during the conversion process. The work included the drilling of 70 new wells and extensive modifications to the platforms.

The high recovery factor is largely thanks to the Statfjord Late Life project, lifting the horizon towards 2025. This means that the old oil giant Statfjord will still be producing when a new giant, Johan Sverdrup, has started its 50-year production.

“Statfjord actually taught the Norwegian oil industry to stand on its own legs and has been key to the development of gas transport solutions in the North Sea. The field has produced more than two billion barrels of oil more than we ever thought possible when we began. That’s largely due to all the talented people who have worked on this great field for 40 years,“ Hege Flatheim, director of Statfjord says.

Press release