Grosbeka appraisal finds Mid-Jurassic oil

Offshore staff

OSLO, Norway -- Wintershall Norge has completed drilling of two delineation wells on its Grosbeak oil and gas discovery in the North Sea.

Grosbeak was originally drilled in 2009 in license PL 378, the well proving hydrocarbons in the Sognefjord formation and in Brent Group Upper/Mid-Jurassic reservoir rock.

According to the Norwegian Petroleum Directorate (NPD), the two latest wells were both drilled by theSonga Dee in 359 m (1,178 ft) water depth, 2.5 km (1.5 mi) northeast of the discovery well and 10 km (6.2 mi) northeast of the Fram field.

Well 35/12-4 S was drilled in the southeastern part of the structure, encountering a 40-m (132 ft) oil column in the Brent Group (Ness formation) in Mid-Jurassic reservoir rock. Reservoir quality was better than expected, and a successful formation test was performed. The production rate was 800 cm/d (5,032 b/d) of oil with associated gas, via a 44/64-in. nozzle opening. Maximum production rate was estimated at 1,250 cm/d (7,862 b/d).

Well 35/12-4 A was drilled at the top Brent Group to study the Grosbeak’s northeastern extent. Within the upper part of the Ness formation it encountered thin alternating layers of sandstone and carbon, but no hydrocarbons.
The partners plan to assess whether the discovery warrants development with other finds in the area. However, further delineation will probably be needed, NPD says.

Songa Delta now heads to the Norwegian Sea to drill wildcat 6607/12-2 S in PL 127 for Total.

07/18/2011