Johan Sverdrup Johan Sverdrup is one of the five largest oil fields on the NCS and one of the most important industrial projects in Norway for the next 50 years. Martin Linge The Martin Linge development is located 42 kilometres west of Oseberg. Equinor became operator of the field on 19 March 2018. With estimated recoverable reserves of 8bn barrels, Clair oil field is the biggest oil field in the North Sea and Europe. Image courtesy of Chevron Corporation. Discovered in 1974, the Statfjord field started producing in 1979 and holds has approximately 4.2bn barrels of oil. However, 94% of known oil is concentrated in fewer than 1500 giant and major fields. Most of the world's largest oilfields are located in the Middle East , but there are also supergiant (>10 billion bbls) oilfields in Brazil, Mexico, Venezuela, Kazakhstan, and Russia.