They have confirmed a subsea development tied back to an FPSO would be feasible, and have opted for a phased drilling program. The initial focus will be on the northern part of the Sea Lion field, followed by a subsequent southern development accessing remaining parts of Sea Lion and taking in other current or future discoveries in the area.
Premier is targeting project sanction for the end of 2014, and is negotiating for a rig for a further exploration campaign next year.
To date the partners have commissioned about 70 separate studies for Sea Lion. These have included metocean studies; FPSO design, including turret design and topsides layout; flow assurance methodologies; subsea equipment design and installation; the dynamic reservoir model; artificial lift; well trajectories and completions; and export routes. The studies have either finished or are nearing completion.
Drilling on the northern area is designed to recover 284 MMbbl, with the southern area targeting a further 110 MMbbl. There is uncertainty over the possible presence of a gas cap in the western part of Sea Lion – without this, a further 65 MMbbl could be recovered via the first-phase wells.
An exploratory well will be drilled at some point to try to resolve the issue. Whatever the outcome, Premier anticipates plateau production of around 100,000 b/d.
Although an FPSO would be viable, other conceptual studies have indicated that a TLP with an integral drilling rig may offer cost savings while providing better motion characteristics and flow assurance options.
Work is under way to optimize the design specifications for both solutions, with a final concept decision to be taken at the end of this year. Timing for first oil will depend on the final scheme configuration.
During 2013, the partners have been defining and maturing leads and prospects across their north Falklands basin acreage. As a result, they plan at least three exploration wells with multiple stacked targets.
One of the wells will be on the Zebedee structure, testing the extent of the proven F2 sequence toward the south as well as the older F3 sequence. Rockhopper estimates oil in place here at 1 Bbbl.
The well on the gas cap on the western flank will also test the deeper potential Chatham prospect. Results in both cases will be incorporated into planning for the Sea Lion development.
As for the contracting strategy for the rig there are three options. First, an independent exploration campaign; second, use of the same rig for exploration and development drilling; third, sharing the same rig with other operators planning drilling programs in the area.
Rockhopper says three slots were included for the partners in a recent enquiry by another Falklands operator for a rig in late 2014 or early 2015.