Gullfaks is an oil and gas field in the Norwegian sector of the North Sea operated by Equinor. It was discovered in 1978, in block 34/10, at a water depth of 130-230 meters.[1] The initial recoverable reserve is 2.1 billion barrels (330×10 6 m3), and the remaining recoverable reserve in 2004 is 234 million barrels (37.2×10 6 m3). This oil field reached peak production in 2001 at 180,000 barrels per day (29,000 m3/d). It has satellite fields Gullfaks South, Rimfaks, Skinfaks and Gullveig.[2]
The project consists of three production platforms Gullfaks A (1986), Gullfaks B (1988), and Gullfaks C (1989).[1] Gullfaks C sits 217 metres (712 ft) below the waterline and the height of the total structure measured from the sea floor 380 metres (1,250 ft),[3] making it taller than the Eiffel Tower. Gullfaks C holds the record [4] of the heaviest object that has ever been moved to another position, relative to the surface of the Earth with a total displacement between 1.4 and 1.5 million tons.[5] The platform produces 250,000 barrels per day (40,000 m3/d) of oil. The Tordis field, which is located 11 kilometres (6.8 mi) south east of Gullfaks C, has a subsea separation manifold installed in 2007 which is tied-back to the existing Gullfaks infrastructure.[6][2]
Between November 2009 and May 2010 a well being drilled from Gullfaks C experienced multiple well control incidents which were investigated by Petroleum Safety Authority Norway and summarized in a report released on 19 November 2010. The report stated that only chance prevented the final and most serious incident on 19 May 2010 from becoming a full-scale disaster.[8]
The reservoir consists of delta sandstones from the Middle Jurassic Brent Group, shallow-marine Lower Jurassic Cook Formation sandstones, and the fluvial-channel and delta-plain Lower Jurassic Statfjord Formation.[1]