Statfjord Field--A North Sea Giant

摘要: Statfjord, largest single oil field in the North Sea, is located on U.K.-Norwegian boundary between 61° and 61°30^prime N lat. Initial estimates are that about 11% of lies U.K. waters. Its discovery, March 1974, was based interpretation seismic reflection surveys extrapolation a productive regional trend. Two principle sandstone reservoirs, Middle Jurassic Brent Lower Jurassic-Upper Triassic contain reserves order 3 billion bbl within area approximately 20,000 acres (580 sq km). Reservoir properties excellent, with permeabilities darcies. The extends northeasterly 15.5 mi (24.8 km) averages 2.5 width (4 Tilted fault blocks form primary hydrocarbon trap at Statfjord as throughout East Shetland basin. structural-stratigraphic formed by westward tilting erosion major block. deltaic sands underlying continental (fluvial) truncated middle to late Kimmerian unconformities crest east flank structure which marked system. Overlying onlapping Cretaceous shales seal trap. Organically rich Upper provide an excellent source. Reservoirs have separate oil-water contacts. Normal faulting separates from southwest. Joint development Norway utilizes "condeep" type gravity platforms initial offshore loading. Development drilling 'A' platform (towed location May 1977) began 1978. First production expected 1979.