Equinor’s first discovery this year made near the Troll field in the North Sea

Source: press release, 5 February 2021

Røver Nord discovery in the North Sea
Røver Nord discovery in the North Sea (illustration: Equinor)

Equinor and partners DNO Norge, Petoro and Wellesley Petroleum have struck gas and oil in production licence 923. Recoverable resources are estimated at between 7 and 11 million standard cubic metres of oil equivalent, corresponding to 44 to 69 million barrels of oil equivalent.

“It is inspiring to see how creativity, perseverance and new digital tools result in discoveries that form the basis for important value creation, future activity and production in accordance with Equinor’s climate ambitions,” says Nick Ashton, Equinor’s senior vice president for exploration in Norway.

The Røver North discovery adds to a number of discoveries in the Troll/Fram area in recent years. It started with Echino, which gave several answers in the autumn of 2019, and continued with Swisher in the summer of 2020.

Recoverable oil equivalent from these three discoveries can already measure against the total production from fields like Valemon, Gudrun and Gina Krog. And the exploration continues. Equinor and the partners have matured several neighbouring prospects. The Blasto and Apodida prospects in production licence 090 will be drilled after Røver Nord.

The first discovery this year was made in one of the most mature areas of the Norwegian continental shelf. After more than 50 years of exploration drilling there are still many unknown pieces in the geological jigsaw puzzle. For each exploration well that is drilled, a new piece is put into place.

Geologists, geophysicists and other subsurface personnel gain new insight and understanding which later forms the basis for new exploration opportunities. This is done in parallel with the ever-increasing use of new digital tools. In addition, the prospects drilled today face ever-stricter requirements for CO2 emissions per barrel produced.

“The discovery is a direct consequence of thorough subsurface work in the Troll/Fram area over many years, and shows the importance of not giving up, but starting over, looking at old issues from new angles. Exploration thus creates great values for society, at the same time as the resources can be realised in accordance with the requirements for CO2emissions through the value chain, from discovery to consumption,” says Ashton.

Exploration well 31/1-2 S and appraisal well 31/1-2 A in production licence 923 were drilled some 10 kilometres northwest of the Troll field, 18 kilometres southwest of the Fram field and 130 kilometres northwest of Bergen.

The primary exploration target for exploration well 31/1-2 S was to prove petroleum in the Brent group from the Middle Jurassic period and in the Cook formation from the Early Jurassic period. The purpose of 31/1-2 A was to delineate the discovery made in the Brent Group in well 31/1-2 S.

Both wells proved hydrocarbons in two intervals in the Brent Group. Well 31/1-2 S encountered an about 145-metre gas column in the Brent Group (Etive and Oseberg formations) and a 24-metre oil column where the oil/water contact was not encountered. A total of 50 metres of effective sandstone reservoir with good reservoir quality was found in this interval. In addition, 6 metres of oil-bearing sandstone with moderate to poor reservoir quality was struck in the upper part of the Dunlin Group.

Appraisal well 31/1-2 A struck sandstones with good to moderate reservoir quality in the Etive formation and upper part of the Oseberg formation. The lower part of the Oseberg formation contained sandstone with moderate to poor reservoir quality. An estimated total of 41 metres of effective sandstone reservoir was found in the two formations. The well proved 12 metres of oil in the Etive formation, where the oil/water contact was not encountered, and a 17-metre oil column in the Oseberg formation.

The Cook formation proved to be water-filled in both wells, but with moderate to good reservoir quality. The wells were not formation tested, but extensive data acquisition and sampling took place.

The licensees consider the discovery commercial and will explore development solutions in towards existing infrastructure.

The wells are the 1st and 2nd exploration wells in production licence 923. The licence was awarded by the Government in 2018 through the “Awards in Pre-defined Areas 2017” (APA) licensing round.

Well 31/1-2 S was drilled to a vertical depth of 3,439.5 metres below sea level and a measured depth of 3,555 metres. The well was terminated in the Amundsen formation from the Early Jurassic period. Well 31/1-2 A was drilled to a vertical dept of 3,452 metres below sea level and a measured depth of 3,876 metres. The well was terminated in the Cook formation.

The water depth at the site is 349 metres. The well has been permanently plugged and abandoned. The wells were drilled by the West Hercules drilling rig, which will now drill exploration well 31/2-22 S in production licence 090 in the northern North Sea.