OFFSHORE EUROPE

Nov. 1, 2002
Norsk Hydro is pressing for a subsea-shore production system for Ormen Lange, the largest outstanding gas field development in the Norwegian Sea. A floating production platform remains in the running, however, and dual studies will continue through to next month's proposed concept deadline.

Jeremy Beckman
London

Subsea solution for Ormen Lange?

Norsk Hydro is pressing for a subsea-shore production system for Ormen Lange, the largest outstanding gas field development in the Norwegian Sea. A floating production platform remains in the running, however, and dual studies will continue through to next month's proposed concept deadline. The platform, with onboard processing, would export production through existing pipelines to Norway's west coast.

Hydro admits this option may be more economic in capex terms, but the long-distance subsea option with associated onshore treatment plant would score in terms of health, safety, and the environment. The presumed landfall site is Nyhanna. If all goes according to plan, the field should be onstream by October 2007, with compression being added around a decade later.

In the North Sea, Hydro has gained Norwegian government backing for a $360-million gas export scheme on Visund, scheduled to start up in 2005. Currently, gas from the field is used to drive oil production through the Visund semisubmersible platform. This arrangement will be maintained by stepping up the gas injection rate, which will in turn require installation of a new injection module in addition to a gas export module. Supplies will be piped through a spur link to Statoil's Kvitebjørn export pipeline, which will be laid directly to the process terminal at Kollsnes.

BG is progressing toward first gas from its five-field Juno project, the hub of which is the Minerva platform, built and recently installed by Heerema.

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Statoil recently claimed that Kvitebjørn, due onstream in fall 2004, would emit very low levels of nitrogen oxide and carbon dioxide, compared with other Norwegian offshore installations. This is due partly to use of the high reservoir pressure to drive the gas to the shore, thereby limiting energy requirements on the platform. Also, the wellstream temperature will be exploited to process produced condensate, obviating the need for substantial heat treatment equipment.

Wintershall builds Dutch base

Clyde Netherlands has changed hands yet again, having shuttled in quick succession between Gulf Canada Resources and Conoco. But while Conoco never concealed its disinterest in Clyde, the new owner, German company Wintershall, is more committed to the Dutch sector, claiming the new assets will propel it to third largest producer on the Dutch shelf.

The package includes 12 operated Dutch North Sea platforms and various undeveloped discoveries in blocks such as Q4, L16, and M1. Assuming ratification from the authorities in Germany and The Netherlands, Wintershall plans to integrate both companies' operations in The Hague into a center of excellence for its offshore activities.

Like the other newly merged super-majors, ConocoPhillips was determining its core offshore arenas. In Northwest Europe, the focus is now on existing production strongholds in Norway and the UK. Of these, the biggest is Ekofisk, where two redundant platforms are up for removal – the 36/22A and 37/4A booster stations for the Ekofisk-Teesside oil pipeline. Seven heavy-lift consortia are currently working on concepts, one of which will be selected next year. ConocoPhillips has also invited tenders for a new platform and two bridge links for its Ekofisk Growth project. The 10,000-ton installation will feature 30 well slots and partial processing capability.

In the UK southern gas basin, the company recently brought onstream Hawksley, the first of five subsea tiebacks to the Murdoch MD platform, and also what it says is the first UK Carboniferous subsea developments. The project, known as Caister Murdoch System III, will initially tie in 500 bcf of new reserves, with a new compression module added later to double capacity both for existing fields and future tie-ins. ConocoPhillips is also a partner to ChevronTex-aco on the Alba Extreme South development in the northern North Sea, which started up last month. Eventually, seven new subsea wells will be in place, including a water injector, helping to sustain production through the Alba Northern platform at a plateau rate of 100,000 b/d.

Ireland seeking drilling revival

Unprecedented field development activity off Ireland (Corrib/Seven Heads) is not being matched by frontier exploration drilling. The only recent spud was on Shell's deepwater Dooish prospect, following a string of unproductive wildcats by various operators off Ireland's west coast. In an attempt to stoke up interest, Ireland's government is to table new frontier acreage every six months in the deepwater Porcupine basin. However, other under-explored basins (Donegal, Erris, Rockall, and Slyne) will not be parceled off for the time being.

The UK government has also announced a fresh initiative to try to stimulate drilling on neglected (fallow) UK North Sea acreage. A group of blocks and undeveloped discoveries, amounting to 39 assets, is being promoted on the License Information for Trading website www.uklift.co.uk. The Fallow Register also lists the relevant license holders contact details. New opportunities will be added as other fields are classified "fallow." The government/industry partnership Pilot has a long-term target to activate 250 blocks and discoveries in this category.

DNO taps further oil in Heather

Norwegian independent DNO is inching toward development of the West Heather oilfield in the UK northern North Sea, first discovered in 1977. This follows a successful appraisal well on the Northern Area, part perforated over a 150-ft section of Brent reservoir. On test, the well flowed 6,000 b/d through a 48/64-in. choke, at a wellhead pressure of 640 psi.

Recoverable reserves from West Heather and the nearby North Terrace structure have now been upgraded to 45 MMbbl, and that figure may rise following the partners' decision to bring forward the third appraisal well, spudded last month by the semi Glomar Arctic IV. This is targeting a bottom-hole location between the two previous wells on West Heather. A strong result could tip the balance to a fast-track subsea tieback to the Heather platform 7 km to the east.

DNO is becoming practiced in reviving large fields in decline. It took on Heather with the platform facing decommissioning. Now it has concluded deals with BP and ConocoPhillips for 99% of two other "tail-end" fields, Deveron and Thistle, plus various interests in local oil and gas trunklines. DNO is aiming for a repeat job on the ageing Thistle platform on the lines of its work on Heather, but final responsibility for decommissioning both sets of facilities will revert to BP and ConocoPhillips.

Danish gas link bid

Danish Oil and Natural Gas wants to build a 40-km, 30-in. pipeline to take gas from Tyra in the Danish North Sea to the B11 compression platform serving the Norpipe trunkline between Ekosfisk and Emden, Germany. The proposed new link, which could be in place by 2004, is also part of DONG's longer-term plan to secure access for Denmark to European gas supplies.

DONG has also farmed into the Statoil-operated F006 license on the Faeroese shelf through snapping up ConocoPhillips' 20% share. DONG is already partnering Amerada Hess on a well drilled recently on UK block 204/16 by the drillship West Navion, at the southern end of the Faeroe-Shetland channel. Amerada hopes to prove up an extension of Marjun, the only discovery to date in Faeroese waters.