A consortium led by BG Group has found an oilfield in the North Sea, just over 60 miles off the coast of Norway, which its exploration partner estimates could run to as much as 150 million barrels.
The test well is north-east of the Snorre field, on an extension of the Tampen Spur which has proved to be an oil reservoir from the Jurassic period between 145 and 200 million years ago.
The UK group is loath to make predictions about the potential scale of the field until further tests have been run. But Revus Energy – the Norwegian exploration and production group that, along with Germany's RWE-Dea, makes up the consortium holding the concession for the Jordbaer prospect – says initial investigations yielded a rate of 7,500 barrels per day.
"This discovery is very promising and of great importance to Revus," Harald Vabø, the Revus chief executive, said. "It is too early to estimate how much oil has been discovered in this well bore, but we do believe that as a consequence of the discovery, there is a relatively high probability this area could contain enough oil and gas to double Revus's current reserves and contingent resources."
Revus estimates the whole Jordbaer area contains up to 480 million barrels, of which around one third, or 150 million barrels, could be in the latest successful well.
Despite the optimism from its partners, BG Group remains reticent. "This well is a key play and the results we have seen so far are encouraging, but it is too early to draw any conclusions on the size and scale of the reservoir," a spokeswoman said.
The exploration drilled to 4,057 metres below the sea bed, under 400 metres of water, using a semi-submersible "Bredford Dolphin" facility. The well will now be permanently plugged and abandoned. Development of the site will involve drilling new wells.