MORE WELLS DUE ON PRODUCTION IN U.K., NORWEGIAN N. SEA FIELDS

More production equipment is in place in the North Sea.

Here's what has happened:

Texaco Ltd. installed three subsea structures in 450 ft of water in Strathspey field on U.K. Block 3/4a.
Elf Petroleum Norge AS completed installation of subsea equipment on three wellheads comprising the Lille Frigg development, due for start-up in January 1994. Lille Frigg lies in Norwegian Block 25/2a, east of the main Frigg field in Block 25/1a.
Tim Eggar, U.K. energy minister, inaugurated Elf Enterprise Petroleum Ltd.'s Piper B oil and gas complex on Block 15/17, about 120 miles northeast of Aberdeen. The complex holds production facilities for Piper, Saltire, and Chanter fields. Elf Enterprise is a partnership of Elf Aquitaine 66 2/3% and Enterprise Oil 33 1/3%.

STRATHSPEY

Texaco emplaced a 950 metric ton subsea production manifold in Strathspey field using Saipem U.K. Ltd.'s M7000 heavy lift vessel.

At the same time, Stolt Comex Seaway Ltd., Aberdeen, installed a launcher unit and subsea isolation valve skid near Central Ninian platform on Block 3/3.

Dolphin Drilling Ltd., Aberdeen, began completion work on one of two remote wells that lie more than 1 mile from the Strathspey manifold. The field is due on stream in the fourth quarter.

Strathspey is one of three subsea field developments tied back to Chevron U.K. Ltd.'s Ninian complex by other operators. Strathspey reserves are estimated at 80 million bbl of oil and 330 bcf of gas, with a further 10 million bbl of natural gas liquids expected.

Other fields producing through Ninian are Lyell, operated by Conoco (U.K.) Ltd., and Staffa, operated by Lasmo plc (OGJ, Apr. 12, p. 32).

LILLE FRIGG

The three Elf wells will be tied back to Frigg platform this summer. Lille Frigg is Norway's first high temperature/high pressure development using subsea technology.

Lille Frigg reserves are estimated at 23 bcf of gas. The main Frigg field reserves originally were placed at 6.4 tcf of gas. Production began in 1977.

Elf has also begun predrilling four wells for Froy field development on Blocks 25/2a and 25/5. Froy will be developed using an unmanned steel platform, exporting oil via Oseberg platform in Block 30/5a. Gas sales have not been arranged, but exports most likely will move through Frigg.

Froy field reserves are estimated at 100 million bbl of oil and 120 bcf of gas. Production is to start in January 1995. Five more wells will be drilled from the platform, making five producers and four water injectors.

PIPER COMPLEX

Combined oil and gas flow from Piper, Saltire, and Chanter fields will rise gradually to a 130,000 b/d plateau. All went on stream this year-Piper B Feb. 3, Chanter Apr. 26, and Saltire May 23.

Piper is destined to hit 73,000 b/d, Chanter 10,000 b/d, and Saltire 45,000 b/d. In addition, the fields will produce a combined 80 MMcfd of gas by yearend.

Piper B oil production moves by pipeline to Elf Enterprise's terminal at Flotta, Orkney Islands. Gas is processed on the Piper B platform, then shipped to the U.K. through the Frigg gas system.

The three fields hold estimated reserves of 322 million bbl of oil and 127 bcf of gas. They were developed by a combine led by Elf Enterprise Caledonia Ltd. 36.5%, Texaco Britain Ltd. 23.5%, Lasmo North Sea plc 20%, and Union Texas Petroleum Ltd. 20%.

Elf Aquitaine said design of the Piper B and Saltire A platforms incorporates significant advances in safety technology, including free fall lifeboats and emergency shutdown valves, subsea and on deck, on all hydrocarbon pipelines.

There are two escape routes from every point on the platforms. It is designed so that at least one will be available and safe for at least 60 min in an emergency.

In addition, design of the Saltire platform includes facilities to control operations remotely from Piper B platform.