The wells were drilled about 20 km west of the discovery well 7220/11-1 (Alta) and about 50 km southwest of the discovery well 7220/8-1 Johan Castberg.
The primary exploration target for wildcat well 7219/12-2 S was to prove petroleum in Early Jurassic reservoir rocks (Nordmela formation). The secondary exploration target was to prove petroleum in Late Triassic/Early Jurassic reservoir rocks (Tubåen formation). In wildcat well 7219/12-2 A, the primary exploration target was to prove petroleum in Early Jurassic/Middle Jurassic reservoir rocks (Stø formation). The secondary exploration target was to prove petroleum in Late Triassic/Early Jurassic reservoir rocks (Tubåen formation).
Well 7219/12-2 S encountered a total gas column of 22 m in the Nordmela formation, of which about 20 m were in sandstone layers with good to moderate reservoir quality. Aquiferous sandstone layers were encountered in the Tubåen formation with good reservoir quality and in the Fruholmen formation with varying reservoir quality from good to poor. Gas/water contact was encountered. Preliminary estimates indicate that the size of the discovery is less than 0.5 billion sm3 of recoverable gas and the assessment is that the discovery is not profitable.
Well 7219/12-2 A encountered aquiferous sandstone layers in the Stø and Nordmela formations, with good reservoir quality. The well is classified as dry.
The wells were not formation-tested, but extensive data acquisition and sampling have been carried out.
These are the fourth and fifth exploration wells in production licence 533. The licence was awarded in the 20th licensing round in 2009.
Well 7219/12-2 S was drilled to a vertical depth of 1829 metres and a measured depth of 2075 metres below the sea surface, and was terminated in the Fruholmen formation in the Upper Triassic. Well 7219/12-2 A was drilled to a vertical depth of 1618 m and a measured depth of 1878 m below the sea surface, and was terminated in the Nordmela formation in the Lower Jurassic.
Water depth is 337 m. The wells will now be permanently plugged and abandoned.
Wells 7219/12-2 S and 7219/12-2A were drilled by the Leiv Eiriksson drilling facility, which will now proceed to drill wildcat well 7219/12-3 in the same production licence.
Read the article online at: https://www.oilfieldtechnology.com/drilling-and-production/24112017/minor-gas-discovery-and-dry-well-northwest-of-722011-1-alta-in-the-barents-sea/