Statoil ASA proved a 25-m oil column in the D-structure of the Heimdal formation north of the North Sea’s Grane field.
Appraisal well 25/8-18 S, part of PL169, was drilled to respective vertical and measured depths of 1,863 m and 1,867 m below the sea surface in 129 m of water, and was terminated in the Shetland Group in the Upper Cretaceous.
“Well 25/8-18 S appraised the D-structure and proved substantial additional oil volumes in an excellent sandstone reservoir,” said May-Liss Hauknes, Statoil vice-president for exploration in the North Sea.
The D-structure is on the Utsira High, 7 km north of Grane field and in the immediate proximity of the Grane F oil discovery made by Statoil in 2013 (OGJ Online, May 28, 2013). The D-structure was originally penetrated in 1992 by well 25/8-4, which encountered just 1 m of oil showing about 6 million bbl. That discovery was made by Norsk Hydro Produksjon AS.
“This is a result of a recent reevaluation of the area done by the partnership. New seismic and improved subsurface mapping have given us new confidence in the D-structure and allowed to mature it towards a drilling decision,” Hauknes added.
Gro Aksnes, Statoil vice-president for area development in Operations West, said, “Tie in to the nearby Grane field is one of the development solutions that will be evaluated for the discovery.”
The estimated volume of the discovery is 30-80 million bbl of recoverable oil.
The well, drilled by Transocean Inc.’s Transocean Leadersemisubmersible drilling rig, will be permanently plugged and abandoned. The rig will proceed to carry out permanent plugging of discovery well 25/11-16 (Svalin), also in PL169.
Statoil operates PL169 with 57% interest. Partners are Petoro AS with 30% and ExxonMobil E&P Norway AS with 13%.
