The Noatun gas and condensate discovery is located in the Haltenbanken Area in the Gimsan Basin of the Norwegian Sea.
The asset, discovered in 2008, is operated by Equinor Energy.
The discovery is situated around 15km north of the Njord Field in the Production Licence (PL) 107D. It is expected to be tied in to Njord with expected start-up beyond 2025.
Noatun Discovery Ownership
In 2008, PL 107 licensees were E.On Ruhrgas (30%), Equinor (20%), ExxoMobil (20%), Gaz de France (20%), and Petoro (7.5%).
The Noatun ownership eventually changed to Wintershall Dea Norge (45%), Neptune Energy (22.5%), Equinor Energy (20%), Petoro (7.5%), and Vår Energi (5%).
In May 2024, Equinor and Petoro signed a value-neutral asset swap agreement in the Haltenbanken Area.
As per the agreement, there will be a series in ownership adjustments in multiple assets. This includes Equinor acquiring Petoro’s 7.5% interest in Noatun.
The deal, subject to multiple regulatory approvals and approval by the Norwegian Parliament, will increase Equinor’s stake in the offshore discovery to 27.5%.
Noatun Discovery and Appraisal
At Noatun, gas and condensate were confirmed in September 2008.
The exploration well 6407/7-8, located in the Gimsan Basin, was drilled to prove hydrocarbons in the Ile and Tilje Formations (Noatun C Prospect).
A pilot hole of 8.5-inches was drilled to a depth of 810m and the well was drilled with the semi-submersible installation West Alpha to a total depth of 5,138m in the Early Jurassic Formation.
It penetrated rocks of Quaternary, Tertiary, Cretaceous, and Jurassic age. It was the eighth exploration well drilled in production licence 107.
No shallow gas was discovered while drilling the pilot hole. Gas/condensate was discovered in the Fangst and Båt Groups.
Gas readings were high in the Tertiary and were maximum in the Rogaland Group. Oil was found in the 4,972m to 5,085m and 5,112 to 5,127m intervals in the base Tilje and Åre Formations.
In September 2008, the wellbore was plugged to 4,000m and permanently abandoned as a gas/condensate discovery.
The wellbore was not subjected to drill stem test, but a sidetrack was prepared to know about the water/hydrocarbon contact.
The wellbore 6407/7-8 A was drilled and sidetracked with a kick-off point at 3,900m in September 2008 for appraising the discovery.
The drilling objective of the wellbore was to prove economical hydrocarbons in the structure and define the water/hydrocarbon contact.
The 6407/7-8 A was drilled with the semi-submersible installation West Alpha to a total depth of 5,227m in the Early Jurassic Åre Formation.
From the kick-off point, the wellbore was drilled with Versatherm oil-based mud to the total depth of 5,227m. The drilling also confirmed gas and condensate in the Fangst and Båt Groups.
The results showed no water/hydrocarbon contact. The Spekk Formation and the sections of the reservoir showed high gas readings without any oil.
No fluid samples were taken from the wellbore and its cores were left uncut. In November 2008, the wellbore was permanently abandoned as a gas/condensate appraisal well.
Noatun Discovery Reserves and Development
According to Norwegian Offshore Directorate’s resource estimates, the Noatun Discovery contains 9.9 million standard cubic metres (Sm3) of oil equivalent.
This includes 1.2 million Sm3 of oil, 5.4 million Sm3 of gas, and 3.3 million Sm3 of Natural Gas Liquids (NGL).
Noatun is planned to be developed as a possible sub-sea tie-back field.
The project will be tied-back at the sub-sea level to the Njord Field around 2025. The proposed drainage strategy for the project is pressure depletion in the Lower Jurassic Reservoir.
Commencement of commercial operations at the Noatun Discovery depends upon the available gas capacity on the Njord A.
Contractor Involved
The West Alpha semi-submersible installation was used for drilling the discovery and appraisal wells. The responsible company for the rig is North Atlantic Norway.