STATOIL SETS WORLD MARK FOR HORIZONTAL DRILLING WITH WELL IN NORTH SEA

Norway's Den norkse stats oljeselskap AS has set a world horizontal drilling record in its prolific Statfjord field in the Norwegian North Sea. Statoil's C39 well, drilled from the Statfjord C platform, has a horizontal section of 7,035 ft and is producing about 30,000 b/d. It has a measured depth of 17,567 ft and a true vertical depth of 7,035 ft.

Nov. 18, 1991

3 min read

Norway's Den norkse stats oljeselskap AS has set a world horizontal drilling record in its prolific Statfjord field in the Norwegian North Sea.

Statoil's C39 well, drilled from the Statfjord C platform, has a horizontal section of 7,035 ft and is producing about 30,000 b/d. It has a measured depth of 17,567 ft and a true vertical depth of 7,035 ft.

Statoil said the well cut three fault blocks south of the platform. It ended in a zone that had not been drilled before. This was not productive, but Statoil said it provided considerable geological information. The three fault blocks hold a total of 88.2 million bbl of reserves but could not have been economically developed with three wells, Statoil said.

Earlier this year Statoil set a world record for an extended reach well, also drilled from the Statfjord C platform. The well had a lateral reach of 19,905 ft, measured depth of 23,786 ft, and true vertical depth of 8,850 ft (OGJ, Apr. 15, p. 31).

DRILLING PROGRAM

Statoil has spudded a second horizontal well in the field. The A24, being drilled from the Statfjord A platform, will produce from a number of fault blocks south of the platform. The horizontal section will not be to world record standards.

The drilling program on the three platforms in the field will continue until 1996. About half of the new wells could be horizontal and the balance either extended reach or more normally deviated holes. The exact number of wells to be drilled has not been decided.

The C39 was spudded on June 24 and completed in 97 days. Statoil made considerable use of simulators in planning the well, which used normal horizontal techniques and equipment.

The limit of horizontal drilling has not been reached with this well, said Oystein A. Haaland, drilling engineering manager in Statoil's Stavanger operations.

Statfjord, astride the median line between British and Norwegian waters, is the biggest oil field in the North Sea.

It held original reserves of 3.35 billion bbl and at the end of September 2.185 billion bbl had been produced. Production currently averages about 775,000 b/d.

Statoil's partners in the field are Mobil Development Norway AS, Norske Conoco AS, Esso Norge AS, AS Norske Shell, Saga Petroleum AS, Amoco Norway AS, Amerada Hess Norge AS, Enterprise Oil Norge Ltd., Conoco (U.K.) Ltd., Chevron U.K. Ltd., and BP Exploration.