OSEBERG PLATFORM C PLACED ON PRODUCTION

Sept. 9, 1991
Norsk Hydro AS last week started oil production from the third platform in giant Oseberg field in the Norwegian North Sea. With a productive capacity of 110,000 b/d, Oseberg Platform C boosts field capacity to about 450,000 b/d. The field is expected to reach that production level during the fourth quarter of this year, making it the second largest oil producer off Norway. Norsk Hydro said start-up of Platform C marks completion of development of one of the world's largest offshore oil

Norsk Hydro AS last week started oil production from the third platform in giant Oseberg field in the Norwegian North Sea.

With a productive capacity of 110,000 b/d, Oseberg Platform C boosts field capacity to about 450,000 b/d. The field is expected to reach that production level during the fourth quarter of this year, making it the second largest oil producer off Norway.

Norsk Hydro said start-up of Platform C marks completion of development of one of the world's largest offshore oil fields. It required a total investment of about $5.5 billion (U.S.).

Platform C is a drilling and processing platform consisting of a steel jacket substructure with a modular steel frame deck and modules for processing, drilling, and auxiliary equipment as well as a living quarters unit with 122 berths.

Water depth at the site is 106 m. Eight production wells were predrilled using a semisubmersible rig prior to installation of the steel jacket.

Platform C went on stream about 1 month ahead of schedule and about 3 1/2 years after receiving government approval in January 1988.

GAS INJECTION

The Oseberg development includes a small adjoining field, North Gamma, which will produce gas through the first horizontal well placed on permanent production in the North Sea. The gas will be injected into the main Oseberg reservoir from Oseberg Platform C.

Through the Troll-Oseberg gas injection project, Oseberg is the first major North Sea field to use external gas resources to boost oil recovery.

The Platform C project, including North Gamma development, carries a price tag of about $1.5 billion (U.S.).

Oseberg oil production started in December 1988 from the field center consisting of Platforms A and B. Platform C lies 14 km north of the field center. Oil moves ashore through a 115 km pipeline laid in as much as 360 m of water to Sture terminal on Norway's west coast, just north of Bergen.

Oseberg field reserves are about 1.5 billion bbl of oil and 92 billion cu m of gas, making it one of the largest in the North Sea. Gas production from the field will not start until after 2000.

In the Oseberg area covering North Sea Blocks 30/6 and 30/9, Norsk Hydro has made several other discoveries that are being readied for development with facilities connected to Oseberg platforms. That will allow use of processing capacities of those platforms in the second half of the 1990s.

Norsk Hydro operates Oseberg with a 13.75% interest. Its main partner is state owned Den norske stats oljelskap AS with 65.4%. Other partners are Saga Petroleum AS and units of Ste. Nationale Elf Aquitaine, Mobil Corp., and Total.

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