Equinor and its partners in the Gullfaks field will invest NOK2.3bn ($269.5m) for the drilling of seven new wells in order to improve oil recovery in the North Sea field by 17 million barrels.

Gullfaks-recovery

Image: Illustration of the Gullfaks field. Photo: courtesy of Equinor ASA.

Located in block 34/10 in the Tampen area in the northern part of the North Sea, the Gullfaks field, which is contained in water depth of 130-220m, has been in production since December 1986.

Equinor with a stake of 51% is the operator of the offshore field which is regarded as the fourth largest oil field in Norway after the Statfjord, Ekofisk, Oseberg fields. The other partners in the Gullfaks oil field are Petoro and OMV with stakes of 30% and 19%, respectively.

An amended plan for development and operation (PDO) of the oil field has been submitted by Equinor to the Norwegian Ministry of Petroleum and Energy. Under the plan, the partners will drill the seven wells in the Shetland Group, a carbonate reservoir located above the main reservoir of the Gullfaks field.

Equinor development and production Norway executive vice president Arne Sigve Nylund said: “Our ambition is to maintain profitable production from the Norwegian continental shelf (NCS) for several decades. Wells that can be drilled fast and at a low cost, near existing infrastructure, will be a major contributor.”

According to Equinor, drilling on Gullfaks is challenging because of the carbonate reservoir. However, a well test undertaken in 2012 proved that the carbonate reservoir also had an oil production potential.

Since 2013, the Gullfaks partners have invested over NOK1bn ($117.1m) in production wells in the formation, which, till date, have produced an excess of six million barrels of oil from Shetland/Lista phase 1, said Equinor.

The partners believe that they can potentially extract more oil from the Shetland Group by using water injection for which the amended PDO has been prepared.

As part of the Shetland/Lista phase 2 development, seven horizontal wells will be drilled by using existing drilling facilities on the Gullfaks field.

Nylund said: “These formations that used to pose a challenge are now due to producing at a break-even below USD 30 per barrel – I find that to be a nice bonus from Gullfaks.”

Equinor said that although the oil produced from Shetland/Lista is a small contribution to the total reserves of Gullfaks, it is still a significant contributor to the remaining field potential.

The Norwegian oil and gas giant further said that the project also deepens its knowledge of production from carbonate reservoirs, which it can implement in other parts of the world.