Wintershall Norge AS has made an oil discovery near the Vega Sør Field in the northeastern North Sea, the Norwegian Petroleum Directorate (NPD) said in a news release Dec. 10.

Wildcat 35/11-18’s target was to prove petroleum in Middle Jurassic reservoir rocks (the Brent Group) and Upper Jurassic reservoir rocks (sandstones in the Heather Formation), NPD said. Encountering a 275-m thickness of moderate to good reservoir quality in the Brent group, the well proved light oil in the Tarbert and Oseberg formation with columns of 11 m and 3 m, respectively.

In addition, Wintershall said appraisal well 35/11-18 A—which investigated the extent of the reservoir and the hydrocarbon columns—was drilled about 450 m south of the discovery well. The appraisal well proved gas and oil in two Upper Jurassic (the Heather formation) sandstones with net thicknesses of 33 m and 24 m, respectively, with poor to good reservoir quality, the NPD said.

The well encountered oil throughout the Brent group, which is 270 m, with moderate to good reservoir quality and encountered a 46-m column of light oil in the Lower Jurassic (the Cook formation), NPD said in the release. Preliminary estimates place the size of the discovery between 1 and 3 million standard cubic meters of recoverable oil.

Extensive data collection and sampling have been carried out, including two formation tests in the Cook and Oseberg formation in 35/11-18 A. The tests show good flow properties with stable flow pressure and low pressure drop, with good permeability, according to the release.

Well 35/11-18 was drilled to a measured depth of 3,759 m below the sea surface, while the appraisal well was drilled to a measured depth of 4,020 m below the sea surface. Water depth at the site is 366 m. The wells have been permanently plugged and abandoned. The partners in PL 248 will now evaluate the results, NPD said.

Offshore