Jeremy Beckman • London
Total adds Alwyn satellites
Total has discovered a new field in its Alwyn Area production stronghold in the UK northern North Sea. An exploration well on the Islay prospect tested gas and condensate from the Brent reservoir at a rate of 8,800 boe/d.
Islay is in a water depth of 120 m (394 ft) in block 3/15, just east of the 170 MMboe Jura field, which came on stream in May following a tie-in to the Forvie North subsea manifold. From there, the gas heads through an existing pipeline to the Alwyn North platform.
The Jura bundle under tow to the Alwyn Area.
Total developed Jura at a cost of $300 million via two high pressure subsea wells, with temperatures of up to 125° C (257° F). They are linked to Forvie North through a 3-km (1.86-mi) bundle housing an 8-in. (20.3-cm) super-duplex flowline, chemical injection, hydraulic and electrical control lines, with a towhead at either end.
The towhead manifold connected to the Jura wells is the largest assembled to date by Subsea 7 at its site in northern Scotland, weighing around 513 tons (465 metric tons). The dimensions and weight of this structure necessitated construction of a special road and beachhead landing facility in Sinclair Bay for transportation of the towheads to the bundle launch site.
The bundle assembly includes a subsea high integrity protection system (Hipps), reportedly a first for a pipeline bundle; a cryogenic cooling spool; a multiphase flow meter; check valves; and pressure and temperature transducers.
Thistle to host Don developments
Lundin Petroleum’s Thistle platform in the far north of the UK sector will receive and transport oil from the Southwest Don and West Don fields, both due onstream next spring. Operator Petrofac recently secured UK government sanction for its £360 million ($711 million), seven-well development plan, under which the semisubmersible platformNorthern Producer will process fluids from both fields.
Initially, the oil will be offloaded to a tanker, but a few months later, there will be a switch to pipeline export via a newly laid line to Thistle for onward shipment to Sullom Voe, Shetland, through the Brent trunkline system.
Lundin embarked on an overhaul of the Thistle facilities last year as part of a plan to extend the Thistle field life. The program involves reinstallation of the platform’s disused drilling rig, with new drilling and workover activity lined up for this year and next to lift production. Detailed engineering is now under way on modifying the topsides to receive fluids from the two fields, which have combined proven and probable reserves of over 57 MMbbl, according to Petrofac’s partner Valiant Petroleum.
Thistle is one of several mature production centers that may benefit from a change to the UK’s petroleum revenue tax (PRT). The government plans to remove PRT liability for potential incremental projects on 30 existing fields approved before March 1993. According to UK Business Secretary John Hutton, the cumulative benefit could be an increase in the UK’s oil production of 20,000 b/d.
StatoilHydro finds gas in Galtvort
StatoilHydro has proven gas in a previously undrilled area of the Norwegian Sea. Exploration well 6407/8-4 S encountered hydrocarbons in the Jurassic Garn formation while drilling the southern segment of the Galtvort prospect in 266 m (873 ft) of water, 9 km (5.6 mi) northwest of the Shell-operated Draugen field.
Location of the Galtvort gas discovery in the Norwegian Sea.
The semisubmersibleWest Alpha went on to drill a side track targeting the Garn and Ilie formations in an up-dip location. This is the first well in production license 348, awarded in 2004 under Norway’s Pre-Defined Areas round.
Also in the Norwegian Sea, StatoilHydro has government approval for its development plan for the 1.75 bcm Yttergryta gas field, discovered last July. FMC Technologies is supplying the single-well horizontal subsea tree, flow control module, and associated items for the tieback to theAasgard B semisubmersible platform.
Production, due to start next spring, will be regulated by demand on the platform. Yttergryta’s gas will be used to dilute incoming gas from the Smorbukk satellite, which has a higher carbon dioxide content.
Other field news in brief…
London: Ithaca Energy has contracted Bluewater Energy Services to develop its Athena oilfield in the UK central North Sea with the Uisge Gorm FPSO. Using a floater will cut capital outlay by around $200 million, and accelerate first oil by up to one year, Ithaca claims, compared with the alternative option of a subsea link to Talisman’s Claymore field. The FPSO should also accommodate higher flow rates, allowing more rapid depletion. First oil should be achievable at the end of 2009, at around 21,000 b/d.
Copenhagen: DONG Energy has contracted Bladt Industries in Aalborg to build a production platform for its 17 MMbbl Nini East oil field in the Danish North Sea. Like existing installations on the Nini/Cecilie fields, this will be an unmanned satellite exporting its oil to the Siri platform for further treatment. Acergy will manage associated pipeline installations. The estimated cost of the development is DKK2.1 billion ($442 million).
Dublin: The Irish Marine Institute is acquiring 2D seismic for Island Oil & Gas over the Old Head and Schull gas discoveries in the Celtic Sea. The vessel Celtic Explorer is conducting the surveys, designed to target a south-easterly extension to Old Head and to identify low risk exploration prospects close to both fields. Island expects to issue a declaration of commerciality for a joint development of the fields later this year, with first production targeted for 2010.
