The East Shetland Basin is a major oil-producing area of the North Sea between Scotland and Norway. It extends from 60°10′ N to 61°45′ N and 1°36′ E to 3°0′ E. It is 111.3 km north–south and at its maximum 55.8 km east–west.[1]
Oil produced in the UK area is landed at Sullom Voe Terminal in the Shetland Islands. Associated gas flows via the FLAGS pipeline to St Fergus Gas Terminal.
Formation
editThe North Sea Basin is a major oil and gas producing area that has been exploited by Denmark, Norway and the United Kingdom. The basin was formed in the Mesozoic period by tectonic activity during the break up of Eurasia and North America.[2] The northern area of the basin, where significant oil reserves are situated, is known as the Viking Graben. Tilted fault blocks and basins at the northern end of the Viking Graben is the area known as the East Shetland Basin.[2] The oil fields are located at the crests of the blocks, which are of the Triassic to Middle Jurassic age. The source of the oil and gas is the Upper Jurassic (Kimmeridge Clay) shales.[2]
Oil and Gas Fields
editThe UK East Shetland Basin includes the following oil and gas fields and accumulations:[3]
Quadrants and Blocks
editThe UK part of the East Shetland Basin extends over the following Quadrants and Blocks:[1]
- 210/15, 210/20, 210/24, 210/25, 210/30
- 211/7a, 211/8, 211/11 to 211/15 (inclusive), 211/21 to 211/30 (inclusive),
- 2/5, 2/10, 2/15
- 3/1 to 3/20 (inclusive), 3/24
To the East of the UK/Norway median line the East Shetland Basin extends over the following Norwegian Quadrants:[1]
- 25, 30, 31, 33, 34, 36.
This includes the following fields: Statfjord, Snorre, Alpha, Beta, Delta, Gullfaks.
Hydrography
editAs the northern limit of the North Sea the East Shetland Basin plays an important role in the inflow and outflow of water to and from the North Sea.[4] The East Shetland Atlantic Inflow is an alternating inflow of water from the North Atlantic current and the continental shelf edge Slope current. These enter the East Shetland Basin from the north and flow anti-clockwise.[4] The alternating flow affects the salinity of the water which in turn affects the population of zooplankton species such as Calanus finmarchicus which increase in the Spring. Part of the Slope Current enters the East Shetland Basin from the north east and flows south to the east of the north-flowing Norwegian coastal current. The Fair Isle Current originates on the east of the Shetland Islands and flows south in an anti-clockwise pattern.[4]
East Shetland Platform
editThe East Shetland Platform is the area between East Shetland Basin and the Shetland Islands. It includes Quadrants 1, 2, 209 and 210. The Platform includes rocks of the Palaeozoic and Triassic successions which have significant variation of thickness. This may indicate areas where hydrocarbons are trapped.[5]
See also
editReferences
edit- ^ a b c Department of Trade and Industry (1994). The Energy Report. London: HMSO. pp. Plate 6. ISBN 0115153802.
- ^ a b c Miles, Jennifer A (1990). "Secondary Migration Routes in the Brent Sandstones of the Viking Graben and East Shetland Basin: Evidence from Oil Residues and Subsurface Pressure Data". American Association of Petroleum Geologists Bulletin. 74 (11): 1718.
- ^ "Oil and Gas Authority: Oil and Gas Activity". Oil and Gas Authority. Archived from the original on 26 January 2019. Retrieved 22 November 2019.
- ^ a b c Turrell, W R (1996). "Hydrography of the East Shetland Basin in relation to decadal North Sea Variability". ICES Journal of Marine Science. 51: 899–900, 914–5.
- ^ "The East Shetland Platform – a platform to further explore". Retrieved 12 December 2023.