Magnolia Field, Gulf of Mexico, USA

The Magnolia field is located approximately 180 miles south of Cameron, Lousiana, in Garden Banks blocks 783 and 784 in the Gulf of Mexico. Conoco, as operator, holds a 75% working interest in the field with Ocean Energy owning the remaining 25%.

DEEPWATER DRILLING

The field was discovered with the first well drilled by Conoco's Deepwater Pathfinder in May 1999 when it drilled on Garden Banks Block 783 in 4,700ft of water as part of a five-year, $400 million deepwater drilling programme.

The well, drilled to a depth of 16,868ft, encountered hydrocarbon-bearing sections of 150ft to 200ft net.

This was followed by Magnolia GB 783 No2 appraisal well, a 6,000ft westerly step-out from the discovery. This was drilled to a total depth of 17,435ft. The well encountered oil bearing sand in excess of 400ft net, with 300ft net in one continuous unit. After logging operations were completed, the well was sidetracked 3,000ft to the southwest to provide an additional penetration of the main pay sand. The sidetrack encountered 400ft net of oil-bearing sand. It has been estimated that in total, the field could yield more than 150 million barrels of oil equivalent in future production.

TENSION LEG PLATFORM

The Magnolia field will be developed by a Tension Leg Platform (TLP), which will be installed in 4,700ft of water, a record depth for this type of floating structure. This will be located approximately 30 miles from the existing infrastructure, which will enable Magnolia to be a regional off-take point for future developments or third party tie-ins located in Southeastern Garden Banks area.

All previously drilled wells will be converted to production wells as part of the eight wells required to bring the Magnolia Field into full production. Initial estimates have put the total development bill at $600 million.

LEAD CONTRACTORS

ABB Lummus Global Americas of Houston has been awarded the contract for design, procurement, project management and construction services for the TLP hull and associated systems. This innovative deepwater hull will consist of four circular columns connected at the bottom by rectangular pontoons. At the base of each column, a pontoon will extend outward to support two tethers, which will be connected to pile foundations on the seabed.

Alliance Engineering of Houston has been awarded the contract for topsides engineering, procurement and project management services. The topsides design will incorporate state-of-the-art lightweight design technology, which will reduce costs and preserve flexibility in future production operations.

The design capacity of the production facilities will be 50,000 barrels of oil per day and 150 million standard cubic feet of gas per day. First production from the field is anticipated in the fourth quarter of 2004, with peak production occurring in 2005.

The Magnolia TLP will be connected to the Shell-operated platform hub at Garden Banks 128, located 50 miles away, by means of two pipelines to Shell's Enchilada platform.

The 16in natural gas pipeline will be constructed and owned by Shell Gas Gathering, and will have a 275 million cubic feet per day capacity.

It will connect into the Shell-operated Garden Banks Gas Pipeline System, which will transport the gas to a variety of pipelines linked to onshore locations.

The 14in oil pipeline will be constructed and owned by Shell Pipeline Company and will have a 75,000-barrel a day capacity. It will then connect into the existing Auger pipeline system.

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