Jubilee moving towards first oil

Offshore staff

ACCRA -- The FPSO Kwame Nkrumah is moored above the deepwater Jubilee field, having arrived in Ghana last month.

According to partner Tullow Oil, much of the subsea equipment has also been installed bar the risers, which will be tied into the FPSO during July and August. The vessel and subsea system will then undergo integration, commissioning and testing ahead of first oil in November or December.

The semisub Eirik Raude is on more complex well completion operations. There were problems with the first completion arising from a downhole mechanical failure, necessitating a workover. However, the partners aim to recover lost time by having the Sedco 702 work in parallel with the Eirik Raude.

At start-up, production should be around 60,000 b/d of oil, rising to 120,000 b/d over the following three to six months. Tullow estimates the Jubilee Phase 1 development cost at $3.35 billion, around $200 million up on the original budgeted figure.

Work also continues on the next phases of the field’s development which will extend plateau output. Under Phase 1a, five to eight infill wells will be tied into the current infrastructure. Up to 20 more wells will follow under Phase 1b, but this will entail expansion of the subsea facilities.

Tullow says the timing of these phases will depend on the performance of both the early wells and the FPSO, but sanction is likely within the next two years.

On Ghana’s West Cape Three Points deepwater license, Tullow says results from the successful Mahogany-5 appraisal well are being incorporated into the field model. Development planning is under way for the southeast Jubilee area, which could take in both independent and satellite development options.

Later in the year, the Atwood Hunter will drill the Teak exploration prospect on West Cape Three Points, with further wells to follow on other Turonian and Campanian targets.

In the Tullow-operated Deepwater Tano license, the Sedco 702 is drilling the potentially high-impact Owo-1 prospect, a 60-day operation including a planned side track. This well is testing 1,400 MMboe upside in the Greater Tweneboa area.

Next up for the rig will be a well on the Onyina prospect in the same license, likely to spud in August. Then the rig will transfer to Jubilee for development work.

Late this year and into 2011, Tullow plans to resume appraisal of the Tweneboa structure with the Tweneboa-3 and Tweneboa-4 wells. This program will include a drillstem test to obtain further data regarding hydrocarbons and reservoir characteristics in support of the current development studies.

Elsewhere in Tullow’s interests off northwest Africa, 3D seismic surveys have been completed over Cote d’Ivoire blocks CI-103 and CI-105. One well is scheduled for both blocks during 2011.

And off Liberia and Sierra Leone, processing of 10,000 sq km (3,861 sq mi) of 3D data is nearing completion, the aim being to define an inventory of drilling prospects. Tullow expects a three-well campaign to start in the next nine months.

The wells will target the same plays opened by the Jubilee and Odum discoveries and extended by the Tweneboa and Venus-B finds. The Cobalt prospect off Liberia, Tullow points out, exhibits a similar seismic character to Jubilee.


07/07/2010