Atlantis Deepwater Oil and Gas Platform, Gulf of Mexico, United States of America
October 11, 2012
Considered one of BP’s most technically challenging projects ever, the Atlantis platform is the deepest moored floating dual oil and gas production facility in the world. Weighing in at 58,700t, it is also one of the largest. BP is operator of Atlantis with 56% ownership, and its partner in the venture, BHP Billiton, has a 44% working interest.
The platform is located 190 miles south of New Orleans in 7,070ft (2,150m) of water, the field itself occupying five blocks – Green Canyon 699, 700, 742, 743 and 744 – with water depths ranging between 4,400ft and 7,100ft (1,338m and 2,158m).
“The Atlantis platform is the deepest moored floating dual oil and gas production facility in the world.”
Initially producing at a daily rate of around 10,000 barrels of oil, Atlantis reached plateau production by the end of 2008. It has a production capacity of 200,000 barrels of oil and 180 million cubic feet of gas a day.
The field has estimated oil reserves of 635,000 million barrels of oil equivalent.
Atlantis deepwater platform production and development
The Atlantis platform employs an integrated semi-submersible design, with the production quarters platform supported by a separate dedicated mobile offshore drilling unit.
In addition to the semi-submersible platform, field development uses a network of wet-tree subsea wells – with the potential for more than 18 to be tied back to Atlantis – while development drilling and well completion involved Global Santa Fe’s submersible rig, Development Driller II, a long- term development unit.
Transporting the oil and gas to existing shelf and onshore interconnections uses the Caesar and Cleopatra pipelines, respectively, which form part of the largest-capacity deepwater line ever built – the Mardi Gras transportation system, which is 65% BP-owned. BHP Billiton has a 25% equity share in the component Caesar pipeline and a 22% stake in Cleopatra.
Crude from Atlantis is transported to the Ship Shoal 332B platform, from where the multiple pipeline connections allow it to reach major US markets and interconnections. Natural gas is channelled along Cleopatra to the Ship Shoal 332A platform, where it interconnects with the Manta Ray gathering system, before being transported to Louisiana along the Nautilus gas transportation system.
The topsides layout consists of three production/utilities modules, amounting to a lift weight of 14,125t. Duffy & McGovern supplied the accommodation, including sleeping and office modules, laundry facilities, recreation areas and galleys, with associated sewage and fresh water tanks. The finished installation has a main power generation capability of 63MW.
Future of Atlantis
BP has a long record of major deepwater developments in the Gulf of Mexico. The start-up of the BP’s long-delayed Thunder Horse platform in 2008 – some three years behind schedule – promoted this still further. It is the largest offshore platform in the world – with a capacity to produce 250,000bpd and 200 million cubic feet of gas a day – and when combined with Atlantis, add around 6.5% to total US production.