Offshore Europe

Jeremy Beckman • London

Total and partner DONG have sanctioned Britain's first gas-gathering system west of the Shetlands. Development of the Laggan and Tormore fields in blocks 206/1a, 205/4b, and 205/5a will incur investments of almost $3.83 billion, and also will be the UK's deepest-water project to date, in 600 m (1,968 ft) water depth.

The two fields have combined reserves of 230 MMboe of gas and condensates. Both will be developed via subsea wells, with production sent through two 140-km (87-mi) multiphase pipelines to a newly built process terminal at Sullom Voe on the main Shetland island. From here, the processed gas will head south through another new 230-km (143-mi) trunkline connecting to Total's Frigg UK pipeline, and onwards to the company's gas terminal at St Fergus, north of Aberdeen. Corus Tubes in Hartlepool, northeast England will supply over 150,000 metric tons (165,347 tons) of pipes in diameters of 18-in. and 30-in. (45.7 cm and 76 cm) for the three export lines.

The Laggan/Tormore project will provide the UK's first dedicated offshore gas trunkline system west of Shetlands.

Start-up is scheduled for 2014, with the two fields delivering 500 MMcf/d of gas at peak, and 93,000 boe/d including condensates. Total had tried to persuade other operators of stranded gas fields in the region to share the costs of a wider-ranging scheme. None came forward, although according to field analysts BritBoss, there is sufficient spare capacity in the pipelines to accommodate gas from Chevron's Lochnagar/Rosebank fields close to the Faroe Islands median line and BP's Clair Ridge project, a short distance northwest of Shetland.

Another big spender is ConocoPhillips (COP), which is set to commit to two major new projects in the Norwegian and UK sectors.

The company's latest plan to broaden development in the Greater Ekofisk Area involves adding two large wellhead platforms, one each to the Ekofisk and Eldfisk fields. The proposed 36-slot Ekofisk 2/4 Z would be bridge-linked both to existing installations at the Ekofisk field center and to a new accommodation platform, 2/4 L. The 2/4 Z platform would produce reserves from Ekofisk's southern extent, and may be supported by subsea water injector wells.

Sembcorp Marine Singapore already has picked up the $550-million contract for the 10,000-metric ton (11,023-ton), 552-man accommodation block for 2/4 L, and associated bridges, with construction due to start this summer. Aker Solutions and Mustang performed front-end engineering design for the new facilities.

In the UK central North Sea, Worley Parsons is working on FEED definition for COP's Jasmine Area gas/condensate development. WorleyParsons describes this as its first major platform award in the region. Jasmine, a high-pressure/high-temperature field discovered in 2006, will likely be the UK's largest new project since Nexen's Buzzard.

Hardware should include a wellhead platform connected to an accommodation platform, with production exported to a new riser platform with separation facilities linked to COP's Judy complex. Other reserves from BG's prospective structures north of Jasmine could further extend the scope of the development.

Over the past few years, Statoil's exploration focus on the Norwegian shelf has shifted increasingly to near field drilling of small, prospective structures. The success rate has been high, and the company now is looking to monetize four of these finds with combined reserves of over 140 MMboe as satellite tiebacks, with start-ups during 2012-13.

The fields and the proposed host platforms are Katla to Oseberg Sor, Vigdis Nordost to Snorre, Pan/Pandora to Visund or Gullfaks – all in the North Sea – and in the Norwegian Sea, Gygrid to either Njord or Shell's Draugen complex. Staale Tungevik, the company's head of reserves and business development, says Statoil's goal on fields in this category is to halve the time taken from discovery to production, and to cut development cost for these types of projects by 20-40%, compared with current levels.

Statoil also looks to up the tempo and performance of its production drilling, according to Geir Slora, senior VP for drilling and wells. The company has made progress of late, he claimed, lifting drilling progress from an average of 60 m/day (197 ft/d) in 2007 to 85 m/d (279 ft/d) currently, and rig utilization time over the same period from 80 to 85%.

But there is room for further improvement in operational efficiency and well operations quality, he added. This means in part striving for greater rig, drill installation and well service availability; recovering old wells to free up slots for new wells at some fixed drilling installations; and design changes prior to decisions on new wells in order to reduce costs and increase efficiency.

Mid-size companies are driving much of Norway's wildcat exploration at present. Among the latest efforts, BG has proven oil with its first well on North Sea permit PL 374 S, awarded under the APA 2005 licensing round. The semisubBorgland Dolphin was successful drilling the Cook formation, one of two Lower-Upper Jurassic targets. The location is in 387 m (1,269 ft) of water, 25 km (15.5 mi) northeast of the Snorre field.

In the Norwegian Sea, Centrica Resources appears to have found hydrocarbons in the potentially large Fogelberg prospect while drilling through the Mid-Jurassic Garn formation. According to partner Faroe Petroleum, the structure looks similar to Statoil's Morvin oil and gas field, 10 km (6.2 mi) to the southwest, which is due onstream towards the end of this year. Fogelberg is in license PL 433, in 280 m (918 ft) of water, 10 km north of the Aasgard complex.

Det norske oljeselskap was due to conduct a production test on the oil zone of its recent appraisal well on the Draupne field. The well in North Sea license 001 B identified a 57-m (187-ft) hydrocarbon column in the same reservoir interval intersected in the 2008 discovery well, and also "non-movable" oil in deeper Triassic formations. Draupne could form part of a new hub development in this region centered on Lundin's Luno field.

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