Ekofisk and Early North Sea oil

This chapter offers information on the expansion of the offshore oil industry in two new discoveries in the North Sea. The North Sea in 1969 and 1970 finally yielded two huge oil discoveries—Ekofisk in the Norwegian sector and the Forties in the U.K. sector. Phillips Petroleum, the discoverer of Ekofisk, and British Petroleum, the discoverer of the Forties, both employed the most experienced offshore construction company in the North Sea, Brown & Root, to generate new answers. Ekofisk and the Forties presented technical, economic, and political challenges to the offshore industry. The technical challenge began with the move from about 100 feet of water and wave heights of perhaps 45 feet in the southern North Sea, to depths of 200-500 feet and waves of 75-100 feet in the central North Sea. The North Sea presented another challenge— metal fatigue. One response to such considerations was the basic redesign of the traditional steel jacket. Two important new features emerged for structures in the northern North Sea— the "node" and the "cluster" pile. Both innovations were in response to the increased loads imposed by the deck and the wave. Phillips hired Brown & Root to search for the most efficient way to get started at Ekofisk and suggested converting the 300-foot jack-up rig “Gulftide,” which they had under lease, into a temporary production facility. Phase 1 at Ekofisk required much trial and error to create a temporary production system, but little time was lost to experimentation. Phase 1 began during the winter of 1970-71. As oil from the Gulftide flowed to market, planning and construction of the permanent facilities of Phase II went forward. Brown & Root's work included designing, fabricating, and installing the U.S. portion of fabrication of the twelve-pile field terminal platform jacket, the "A" and "B" drilling and production platforms, the flare structure and deck, several bridges and connecting platforms, and the pipeline system.