Eirin Gas Field Development, North Sea

Eirin is an Equinor-operated gas field located in North Sea, around 9km northwest of the Gina Krog project. Equinor owns 78.2% stake in the field, while Kuwait Foreign Petroleum Exploration Company- subsidiary KUFPEC Norway holds the remaining 21.8%.

Discovered in 1978, Eirin was long part of the Gina Krog Field development. But it was subsequently put on hold.

Equinor submitted a Plan for Development and Operation (PDO) of the gas field in September 2023 to the Ministry of Petroleum and Energy of Norway.

It is estimated that the Eirin Field development will entail a total investment of more than NOK4bn ($360m).

Production from the field is expected to start in 2025.

Once operational, Eirin field will become a new source of gas supplies to Europe. It will also extend Gina Krog’s productive life from 2029 to 2036.

Eirin Field Location

The Eirin field is located in the North Sea, around 250km west of Stavanger, Norway, towards the north of the Sleipner and Gina Krog field.

The field lies in Production Licence (PL) 048 E at a depth of approximately 4,000m. Water depth in the region is around 120m.

Discovery and Appraisal

Eirin was proven as a gas field in 1978.

In August 1978, the 15/5-2 exploration well was drilled by semi-submersible rig Treasure Seeker in the Ve Sub-basin in the North Sea, north of Gina Krog Discovery and Sleipner Vest Field.

The wellbore was located some 7km northwest of 15/5-1, which discovered Gina Krog field.

The main objective of drilling the well was to know the presence of hydrocarbons in Middle Jurassic Bajocian deltaic sandstones and Middle to Late Jurassic Bathonian/Callovian transgressive sandstones.

The well was drilled to a total depth of 4,322m in the Triassic Hegre Group. It penetrated two sandstone intervals with hydrocarbons.

Between 4,035m and 4,055m, a thin Early to Middle Bathonian sandstone was penetrated in the Jurassic.

At 2,792m and 2,828m, weak oil was observed in the Tor Formation. Oil was also found between 3,488m and 3,517m in the Lower Hod and Blodøks formations, and in the Rødby Formation between 3,707m and 3,723m.

In the Triassic region, the logs showed the presence of hydrocarbon saturation (gas) in the sandstones.

Assessing the results, it was classified as a discovery.

The wellbore 15/5-2 R was the re-entry of 15/5-2 wellbore. It was also drilled by Treasure Seeker in November 1979 for production test from the Triassic Reservoir.

In the Triassic Hegre Group, a production test was conducted over perforated intervals from 4,142m to 4,146m and 4,148m to 4,152m.

This test resulted in 304,120sm³ gas and 17.6sm³ liquid hydrocarbons per day.

Eirin Field Development

The Eirin field holds estimated recoverable reserves of 27.6 million barrels of oil equivalent, mostly gas.

It will be developed as a subsea facility and will be tied back to the Gina Krog Platform located in the North Sea.

The development will also include an option for expansion for two to four wells in order to accommodate tie-ins for future discoveries in the area.  The subsea system will be tied-back to Gina Krog via a production flowline and an umbilical.

Initial processing of hydrocarbons produced by Eirin will take place at Gina Krog platform.

Sleipner A facility will receive the condensate obtained from Eirin through a planned oil pipeline from Gina Krog. The facility will also process the rich gas.

The sales gas will be exported to the market through Gassled and the unstabilised condensate will be transported to the terminal at Kårstø.

The production from Eirin will have low carbon dioxide emissions (three kilos of carbon dioxide per barrel of oil equivalents) due to the electrification of Gina Krog and the partial electrification of Sleipner.

Contractors Involved

In June 2023, Equinor awarded a Letter of Award (LOA) to Aker Solutions for the subsea production system and control umbilical for the Eirin Field. This is subject to the Final Investment Decision (FID), approval by Equinor and KUFPEC Norway, and final project negotiations.

The scope of the contract includes a full subsea production system with two vertical subsea trees, one two-slot template including manifold with HIPPS, a control system, a control umbilical and other ancillary equipment.

The deliveries for the order, valued between NOK500m and NOK1.5bn, are expected in 2024 and 2025.

In October 2013, Norwegian-based subsea contractor Ocean Installer selected GE Oil & Gas to provide subsea tie-in connection systems for the offshore field.