Equinor makes marginal oil, gas discovery in North Sea

Equinor Energy AS made a small oil and gas discovery at the Ringand prospect in North Sea production license (PL) 923/923B about 17 km west of Troll field in 304 m of water. 

Preliminary reserve estimates at the discovery are 2-12 MMboe, and thus, the find is likely uncommercial for development in isolation, Equinor said in a release Dec. 17. However, PL 923 borders Troll øst and the Fram area and Equinor will consider development solutions to tie Ringland back to existing infrastructure.

Previous commercially profitable discoveries in the area include 31/1-2 S (Røver Nord) and 31/1-3 S (Røver Sør), which lie within a 25-km radius from the Equinor-operated Troll B platform, a likely host candidate, partner DNO ASA said in a separate release. 

Geological information

Well 31/1-4, the seventh in the license, was drilled by the Deepsea Atlantic drilling rig to a vertical depth of 3,772 m subsea, according to a release by the Norwegian Offshore Directorate (NOD). The well was terminated in the Amundsen formation in the Lower Jurassic. 

The primary exploration target for the well was to prove petroleum in Middle Jurassic reservoir rocks in the Ness, Etive, and Oseberg formations. The secondary exploration target was to prove petroleum in Lower Jurassic reservoir rocks in the Cook formation, NOD said. 

The well encountered a 112-m gas column in the Ness, Etive, and Oseberg formations, as well as a 16-m oil column in the Oseberg formation.

There were 14 m of poor-quality sandstone reservoir in the Ness formation and 46 m of sandstone reservoir in the Etive and Oseberg formations, with poor-to-moderate quality.

In addition, a 13-m gas column was encountered in sandstone with moderate reservoir quality in the Drake formation. The well encountered a 6-m aquiferous sandstone layer with moderate reservoir quality in the Cook formation.

The gas-oil contact was encountered at 3,489 m and the oil-water contact was encountered at 3,505 m below sea level.

The well was not formation-tested, but extensive data acquisition and sampling have been carried out. It has been permanently plugged.

Equinor is operator at PL 923/923B (60%) with partners DNO Norge AS (20%) and Petoro AS (20%).