U.K. GAS DEVELOPMENTS TOP ACTION OFF NORTHWEST EUROPE

Major gas field development projects by British Gas plc and Amoco (U.K.) Exploration Co. top news of activity in the U.K. North Sea.

In other recent action off Northwest Europe:

Chevron (U.K.) Ltd. stopped production from North Sea Alba field for 4 days last month to allow modifications aimed at fixing start-up problems.
Total oil and natural gas liquids production from Northwest Europe averaged 5.27 millon b/d in April, down slightly from the 5.32 million b/d recorded in March.
BP Exploration Operating Co. Ltd. selected contractors for its North Sea Cleeton field compression project. This involves construction and installation of a 2,500 metric ton compression platform to be bridge linked to the existing Cleeton process platform on Block 42/29. Highland Fabricators Ltd. of Nigg, Scotland, will build jacket, topsides, and piles. Stolt Comex Seaway Ltd., Aberdeen, will install the platform. Dresser Rand U.K. Ltd., Aberdeen, will supply compressors. Trafalgar House Offshore Services Ltd., Aberdeen, will carry out hookup and commissioning. Work is expected to take 14 months beginning in spring 1995.
Santos Europe, subsidiary of Santos Ltd., Adelaide, will buy a 32.8% interest in Anglia gas field from Conoco for an undisclosed price. If the deal passes regulatory review, it will be effective retroactive to Jan. 1, 1994. Anglia, in the southern North Sea, has been producing since December 1991. Santos said the purchase will boost its budgeted gas production for 1994 by 5.3%. The acquisition will add 1.15 million bbl of oil equivalent to Santos' production this year along with proved gas reserves estimated at purchase date of more than 50 bcf. Santos' share of gas production from Anglia has been sold under a life of field contract to Total Gas Marketing Ltd. Other joint venture participants in Anglia are operator Ranger Oil (U.K.) Ltd. 37.9% and Amerada Hess Ltd. 29.3%.

BRITISH GAS ARMADA PROJECT

British Gas won approval from U.K. Department of Trade & Industry for development of the Armada group of fields in the U.K. Central North Sea.

A L600 million single platform field development will rely on extended reach drilling for simultaneous exploitation of the three fields.

The Armada fields are Drake on Block 22/5b and Fleming and Hawkins on Block 22/5a. Total reserves are estimated at 1.2 tcf of gas and 70 million bbl of condensate.

Production is to begin in October 1997 and expected to last 20 years. Average gas production is pegged at 350 MMcfd.

Gas will be processed on Armada platform and exported via two subsea pipelines connected to the Central Area Transmission System (CATS) riser platform.

The existing CATS terminal at Tees-side will be expanded by operator Amoco in an f:80 million ($120 million) project that will connect CATS to the U.K. national gas grid for the first time.

British Gas will take 225 MMcfd of gas from Armada, and electricity generator National Power plc will take 100 MMcfd. Independent gas supplier Yorkshire Energy Ltd. will take as much as 30 MMcfd for direct sale to customers.

About 20,000 b/d of light oil will be sent from Armada platform through the BP Exploration Operating Co. Ltd. Forties pipeline to Cruden Bay.

British Gas let contracts for design of the platform topsides and jacket to London's AMEC Engineering Ltd. and John Brown Engineers & Constructors Ltd., respectively.

The platform will stand in 89 m of water, with its 6,000 ton, four leg jacket supporting 15,000 tons of topsides. Installation is scheduled for March 1997.

British Gas said 42100 million ($150 million) of the total project cost was reserved for development drilling and platform modifications after 2000.

Armada field interests are operator British Gas 46.27%, Amoco 18.2%, Fina Exploration Ltd. 11.53%, Phillips Petroleum Co. U.K. Ltd. 11.45%, Yorkshire 6.97%, and Agip (U.K.) Ltd. 5.58%.

AMOCO GAS PROJECTS

Amoco secured Department of Trade and Industry approval for a L46 million ($69 million) development of two southern North Sea gas fields.

Block 49/23 Bessemer field and Block 53/5a Davy field each will be developed with a new design of minimum facilities platform tied back to Indefatigable field.

Amoco let a L14 million ($21 million) contract to Brown & Root Highland Fabricators, London, for engineering, procurement, installation, and commissioning of the two platforms.

The Amoco Minimum Offshore Supporting Structure (Amoss) is a single leg, monotower design that Amoco says has never been used in the U.K. North Sea and offers significant cost savings over conventional four legged structures.

Engineering and fabrication work will start in August, with platform installation scheduled for March 1995. Gas production is to begin October 1995 at a total maximum 210 MMcfd.

The contract includes an option for a third Amoss platform for an unspecified field. Amoco is considering development of nearby Beaufort field via Indefatigable field facilities (OGJ, Nov. 1, 1993, p. 28).

Amoco also let a L9 million ($13.5 million) contract to British Steel plc for manufacture of 25 miles of 16 in. diameter pipeline and 25 miles of 4 in. diameter pipeline linking the platforms with Indefatigable. Allseas Marine Contractors SA, Chatel St. Denis, Switzerland, won the 4723 million ($34.5 million) contract for pipelaying, to begin in September and take 2 months (OGJ, July 4, P. 35).

CHEVRON ALBA SHUTDOWN

Production restarted June 25 from Block 16/26 Alba field, which was developed using a minimum facilities platform and floating storage unit.

During the shutdown Chevron worked on gas compression and waste heat recovery systems, process vessel instrumentation, and control software in the tanker's emergency shutdown system.

"In a minimum facilities development you can't hide anything," said Alba Asset Manager Alan Higgins. "Alba's gremlins have been out in the open from the first."

The biggest problem has proved to be control logic problems on the tanker, where a "tremendous number" of shutdowns have been executed automatically when only an alarm signal was necessary.

"We are trying to simplify the logic software," said Higgins. Alba was brought on stream in December 1993.

Chevron is assembling a team to promote third party processing, storage, and export business for Alba. Several smaller operators were said to have development prospects in the Alba area.

Higgins said the company also is looking at options for development of South Alba field. Possibilities under consideration include subsea tieback to Alba or the future Britannia development and a floating production vessel.

PRODUCTION SLIDE

The fall in production off Northwest Europe was due to reduced output from Norway, said Wood Mackenzie Consultants Ltd., Edinburgh. Norwegian oil and NGL production averaged 2.56 million b/d in April, down from 2.63 million b/d in March.

Statfjord C platform was closed down for scheduled maintenance Apr. 21 - May 4, taking the fields' average output down to 547,000 b/d in April from 621,000 b/d in March.

Snorre production was reined to an average 171,000 b/d in April from 990,000 b/d in March. This was attributed to technical problems with the first stage separator and a gas export compressor.

U.K. offshore oil and NGL production averaged 2.36 million b/d in April, up from 2.34 millon b/d in March. Onshore production was 95,000 b/d, up from 87,000 b/d in March.

Flotta terminal throughput was reduced by scheduled maintenance, to 215,000 b/d in April from 290,000 b/d in March. On May 2 Piper and Saltire fields were shut in after an explosion. Output is expected to resume in June.

Danish oil and NGL output averaged 193,000 b/d in April, the same as in March. Dutch oil output fell slightly to 61,000 b/d in April from 63,000 b/d in March.

GAS OUTPUT

Norwegian gas production averaged 3.05 bcfd in April, up from 2.9 bcfd in March. East Sleipner field production was said to have been cut in late March/early April by a flare tip problem.

U.K. gas production was 6.87 bcfd in April, down from 8.17 bcfd in March. U.K. imports of Norwegian gas during April were estimated at an average 350 MMcfd.

Dutch offshore gas production was 2.25 bcfd, down from 2.26 bcfd in March. Danish gas production fell to 479 MMcfd in April from 567 MMcfd in March, while Irish output fell to 251 MMcfd from 276 MMcfd.