Troll B platform; Credit: Øyvind Hagen/Equinor

Fresh oil & gas discovery in North Sea brings another Troll tie-back to the table

Norway’s state-owned energy giant Equinor has made a new oil and gas discovery near the Fram field in the North Sea off Norway, using an Odfjell Drilling-owned rig. This is Equinor’s eighth discovery in the area since 2019.

Troll B platform; Credit: Øyvind Hagen/Equinor

Equinor has concluded the drilling of a wildcat well well 35/10-9 on the Heisenberg prospect in production licence 827 S, where Equinor holds an ownership interest of 51 per cent, while its partner, DNO Norge, holds the remaining 49 per cent. This is the second exploration well in this licence, which was awarded in APA 2015.

The Norwegian giant secured consent for exploration drilling in November 2022 for this prospect. The wells were drilled using Odfjell Drilling’s Deepsea Stavanger rig. The water depth at the site is 368 metres. The well was drilled 10 kilometres northwest of the Fram field and about 140 kilometres northwest of Bergen.

The Norwegian Petroleum Directorate (NPD) revealed on Thursday, 14 March 2023, that the objective of the well 35/10-9 was to prove petroleum in reservoir rocks in the Hordaland Group from the Paleogene. The well encountered a 6-metre gas column over an oil column of around 8 meters in the Hordaland Group in sandstone layers totalling 14 metres, with moderate reservoir properties.

According to the NPD, the gas/oil contact was encountered at 1,557 metres below sea level, however, the oil/water contact was not encountered. The preliminary estimates place the size of the discovery between 3.8 and 13.3 million Sm3 recoverable oil equivalent.

Based on the NPD’s statement, the licensees will consider delineation of the discovery and tie-in to existing infrastructure in the area. While the well was not formation-tested, extensive data acquisition and sampling have been carried out.

Furthermore, the well 35/10-9 was drilled to a vertical depth of 1,779 metres below sea level and a measured depth of 1,809 metres. It was terminated in the Rogaland Group from the Palaeocene. The well has been permanently plugged and abandoned.

The Deepsea Stavanger rig will now drill wildcat well 6406/5-2 in production licence 255B in the Norwegian Sea, where Equinor is the operator.

Equinor’s second discovery near Troll field in 2023

In a separate statement, Equinor confirmed that it had struck oil and gas again near the Troll field in the North Sea. The volumes are estimated between 24 and 84 million barrels of oil equivalent, with slightly more oil than gas.

The Norwegian giant claims that this discovery is considered “commercially interesting,” partly because it can utilise existing infrastructure connected to the Troll B platform. However, an appraisal well is needed to get a more precise estimate of the size before it can be concluded whether the volumes can be recovered. Therefore, the partners are considering drilling the appraisal well in 2024.

Geir Sørtveit, Equinor’s senior vice president for exploration and production west, remarked: “Our Troll exploration play keeps delivering. With discoveries in eight out of nine exploration wells, we are approaching a success rate of 90 per cent.

We plan to further explore the area, while looking at possible development solutions for the discoveries that have been made. We have a good infrastructure in the area and can quickly bring competitive barrels from here to the market at low cost and with low CO2 emissions.”

Deepsea Stavanger rig; Source: Odfjell Drilling
Deepsea Stavanger rig; Source: Odfjell Drilling

The Norwegian player points out that five of the eight discoveries – Echino South, Swisher, Røver North, Blasto, Toppand, Kveikje and Røver South – have been made in licences awarded through APA rounds. This discovery comes just over a month since Equinor together with partners made the Røver South discovery in the same area. Through acquisitions two weeks ago, Equinor increased its ownership interests in four of the discoveries made in the area.

Fifth consecutive discovery in DNO’s core area

Equinor’s partner, DNO, also confirmed the oil and gas discovery at the Heisenberg prospect in the Norwegian North Sea in a separate statement, elaborating that Heisenberg was its fifth consecutive exploration success in the Troll-Gjøa area following the 2023 Røver Sør and 2021 Røver Nord discoveries in PL923 (DNO 20 per cent), as well as the 2022 discoveries of Kveikje in PL293B (DNO 29 per cent) and Ofelia in PL929 (DNO 10 per cent).

As one of the largest acreage holders in the Troll-Gjøa area, DNO has scheduled four more exploration wells in this North Sea exploration hotspot during 2023. The next of these exploration wells, Carmen, will spud in license PL1148 (DNO 30 per cent) next month.