Discovered in 2008 by Maersk Oil, Culzean is a HPHT gas condensate field in the East Central Graben area of the central North Sea, located 260 km off the coast of Aberdeen. It consists of lean gas accumulations in sandstone of the Jurassic Pentland formation and the Triassic Skaggerak formation. Because the two deep reservoirs are sitting beneath traditional reservoirs that play in the North Sea, and beneath the Merganser chalk diapir as well, the area had long remained in obscurity. Fully assessing the area had represented quite a challenge.
The already available seismic obtained from conventional Narrow Azimuth streamer (NAZ) data was not sufficient in terms of data quality. So, a High Density Ocean Bottom Cable (HDOBC) acquisition survey was acquired in 2010/2011. This Full Azimuth data provided a better delineation of the reservoirs by enhanced illumination around the salt diapir.
With resources estimated in the order of 300 million barrels of oil equivalent, Culzean is the largest UK gas field to be sanctioned for quarter of a century. First gas was achieved on June 7, 2019 and is expected to provide 5% of total UK gas demand in the years to come.
Total & Maersk Oil
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