Norne Oil Field
Development
The Alve find led to the discovery of the Norne oil and gas field which was proven in 1992 and brought on stream in 1997. The field has been developed with a production and storage vessel, connected to six subsea wellhead templates. Flexible risers carry the wellstream up to the vessel, which rotates around a cylindrical turret moored to the seabed. Risers and umbilicals are also connected to the turret. The ship has a processing plant on deck and storage tanks for stabilised oil.
Production
Production began from Norne in the Norwegian Sea on 6 November 1997. The Norne field produces around 70,000 barrels per day (11,000 m/d) of medium density, low sulphur, waxy North Sea crude oil. Originally, the shut down of Norne was scheduled for 2014. Nevertheless, Statoil announced in 2015 that they are considering to extend production until 2030.
Reservoir
The Norne reservoir is in Jurassic sandstones. Oil is mainly found in the Ile and Tofte formations, and gas in the Garn formation. The reservoir is found at a depth of 2,500 metres (8,200 ft) below sea level.
Recovery strategy
The oil is produced with water injection as drive mechanism. Gas injection ceased in 2005 and all gas was planned to be exported. In order to avoid rapid pressure depletion in the gas cap, gas will be injected for an extended period of time.