By OGJ editors
HOUSTON, Mar. 17 -- Ireland government officials have approved a development plan for the Seven Heads gas field in the Celtic Sea, and Ramco Energy PLC, London, said gas deliveries are expected before Dec. 31.
Ramco operates the project with an 86.5% interest. Partners are Ireland Petroleum Developments Ltd. 12.5%, and Sunningdale Oils (Ireland) Ltd. 1%. The UK-based Innogy Holdings PLC has agreed to buy Ramco's share of Seven Heads gas production. Seven Heads is 47 km from the Cork coast (OGJ Online, Aug, 6, 2001).
The partners plan to recomplete well 48/24-5A and drill five additional production wells, starting this month. The wells will be linked to a subsea manifold and connected to the nearby Kinsale Head gas field, operated by Marathon International Petroleum Ireland Ltd.
In July 2002, Ramco signed agreements with Marathon that permit additions to, and use of, the existing Kinsale offshore facilities and pipeline to the Inch Terminal—significantly reducing capital expenditure requirements and shortening the development timetable.
The Seven Heads structure is close to the center of the North Celtic Sea basin, where it underlies Blocks 48/23, 48/24, 48/25, 48/28, 48/29, and 48/30. It is west and southwest of Kinsale Head field.
Marathon previously leased the area, and Esso Ireland Ltd. held an interest in it. The lease expired in late 1994. Marathon and Esso drilled five wells on the structure during 1974-90. Four of the wells recorded significant oil and gas shows.
Ramco completed its first appraisal well in October 2001, and it tested a maximum flow rate of 13.7 Mcfd from Upper Wealden sand, which was a higher flow rate than that recorded by any previous wells.
Third-party analysis of Seven Heads reservoir data concluded that the structure holds proven and probable reserves of more than 300 bcf of gas. The reservoir is an east-northeast striking anticline 35 km long and 8 km wide. Gas is contained within Upper Wealden sediments at 915 m.
The Seven Heads development is expected to supply Ireland with 10-15% of its gas requirement for 15 years—a significant development as the country's producing fields have begun to decline, Ramco said.
Ramco awarded the Paris-based Technip-Coflexip unit Technip Offshore UK Ltd. the pipelines and subsea infrastructure engineering, procurement, installation, and commissioning contract worth more than £35 million.
Technip Offshore will install five 8-in. infield flowlines, totaling 27 km, to tie back six wells to a central manifold. It also will install a new manifold at Seven Heads and install all subsea control umbilicals, totaling 65 km, between the remote wells, central manifold, and the Kinsale A platform. The contractor also will test and pre-commission all subsea tie-ins.