Offshore staff
LONDON -- Production from Jubilee, Ghana’s first deepwater oil development, has climbed to around 50,000 b/d since the field came on stream in late-November, according to operator Tullow Oil.
Currently four wells are in service and full capacity of 120,000 b/d should be attained within six months as the remaining five producer wells are completed and come on line. On January 5, the crew achieved the first lifting of Jubilee crude oil, a 650,000 bbl cargo.
Water is being injected into two of the producing wells at a rate of 75,000 b/d, and a further four water injectors will be completed this year to maintain production levels. Gas compression commissioning has started onboard the FPSO, with gas injection to the reservoir due to start next month.
Late last year, planning started for Phase 1a of the Jubilee development, which will comprise five to eight infill wells. This phase will again maintain production rates and extract further reserves. Tullow expects an investment decision to be taken this summer following analysis of reservoir performance and submission of plans to Ghana’s government.
In September, Kosmos Energy, operator of the West Cape Three Points permit, submitted a Declaration of Commerciality for the Mahogany-East discovery (ex-Southeast Jubilee), and development planning is in progress.
The Mahogany-East reservoirs are extensive but generally thinner than in the main Jubilee reservoirs, Tullow says, and will require either a standalone development or a tie-back to the existing Jubilee field subsea infrastructure.
In the Tullow-operated Deepwater Tano license to the west, the recent Tweneboa-3 appraisal well uncovered further gas condensate pay, confirming the Greater Tweneboa Area resource potential.
The Deepwater Millennium rig has since moved to drill the top-hole section of the Tweneboa-4 appraisal and will then spud a first appraisal well on the Enyenra discovery (ex-Owo). Results of the Enyenra-2A should be known by end-February.
Tullow says the appraisal and testing programs are designed to determine the extent and connectivity of the fields and to provide rock and fluid data to refine development studies. The focus is on optimizing recovery of both the light oil discovery at Enyenra and maximizing liquid and gas recovery at the extensive Tweneboa.
Assuming a successful conclusion to the ongoing drilling program, the partners will file a Declaration of Commerciality for the Enyenra and Tweneboa areas with Ghana’s government later this year, to be followed by the submission of a Plan of Development in the first part of 2012. Pending approvals of this plan and project sanction, first production is likely before end-2014.
Currently the Atwood Hunter is drilling the Teak-1 exploration well in the West Cape Three Points block, with results expected in February. The partners then plan to drill other Upper Cretaceous prospects over a sequence up to mid-2011, when the exploration period for the license expires.
The partners have exercised their right to apply for a new West Cape Three Points license. In Deepwater Tano, the partnership agreed a 25% relinquishment of non-prospective acreage within the licence earlier this month.
Farther north-west along the West African Transform Margin, Tullow is a participant in the recent Mercury-1 light oil discovery off Sierra Leone, drilled by the Deepwater Millennium rig.
Anadarko is designing an appraisal program to be combined with the potentially high-impact Montserrado exploration well (Cobalt prospect) in the partners’ deepwater acreage offshore Liberia. First, however, rig capacity has to be secured.
01/28/2011
