The Thistle oil field is a large oil field in the northern sector of the North Sea. The oil field, discovered in September 1972 by Signal Oil and Gas Company,[1] is produced over the Thistle Alpha platform, located 125 nautical miles northeast of Sumburgh, Shetland Islands and 275 nautical miles Northeast of Aberdeen, Scotland.
Licence P236 was awarded as part of the UKCS fourth round in 1972, and the first well on the site was drilled and completed in July 1973 when the Thistle oil field was confirmed as a commercial discovery. The oil has a gravity of 38.4°API.[2] The oil field is estimated to have a reserve of roughly 824 million barrels of oil.[3] The nearby Deveron field, also produced over the Thistle Alpha platform, was discovered in 1972 following the successful completion of a second well on the site. A 1997 seismic re-interpretation site's estimated the reserves to be roughly 61.3 million barrels of oil.[4]
Production commenced for partners BNOC, Britoil and BP on the site in 1978. Ownership of the operations licence for the site was subsequently transferred to DNO in 2003, followed by Lundin in 2004 before the de-merging of Lundin's UK assets in 2010, when EnQuest became the operator. The site is currently operated in partnership between EnQuest and BP, with EnQuest holding over 99% of the total ownership of the site.[5]