|Location:||Foinaven Field, Paul B Loyd Junior|
|Water Temperature:||No data|
|Gas & Oil Company||BP|
|SERPENT Representatives:||Dr Daniel Jones|
The seabed under the Transocean drilling rig Paul B Loyd Junior located at Foinaven, West of Shetland was studied by OBE scientists as part of a scientific industrial ROV collaboration scheme involving BP, Transocean and Subsea 7. The visit highlighted the biodiversity of the seabed around the rig and gave scientists a unique opportunity to look into this relatively unknown yet very important deep sea environment.
The ROVs that are used on a day to day basis on the rig provide a very useful tool for scientists looking into this area. The ROVs are lowered from the rig complete with an underwater winch (Tether Management System) which is attached to the ROV by a 250 metre tether. The ROVs all come equipped with video camera facilities used to fly the vehicle but they may also have a wide range of tools such as highly dexterous manipulator arms, digital still cameras, sonar and a wide variety of specific tools. As a result the ROVs make ideal tools for sampling and scientific experiments.
The PBLJ is one of the deepest water drilling rigs in operation in UK waters. The seabed underneath at 507 metres deep, on the edge of the Faroe-Shetland Channel, has very rarely been studied. It is difficult to know what would be considered a ‘natural’ seabed in this area, because there have been no baseline studies prior to the drilling activity. The seabed around the oil field has large valve structures on top of the wells and pipelines connecting them scattered around the oil field. These structures provide animals with shelter, which, particularly as it is a no fishing zone, attracts large numbers of fish, predominantly Redfish (Sebastes spp.) and Saithe (Pollachius virens). Anglerfish (Lophius piscatorius) and Wolf fish (Anarhichas lupus) can also be found on the fine seabed sediment of drill cuttings around these structures.
Moving away from the structures by 10-20 metres reveals a transition from the fine drill cuttings to a more coarse seabed of sand, gravel and occasional larger boulders, probably the natural seabed type for the area. This site is home to a wide variety and surprising number of invertebrate species. Many of the larger rocks are covered with sponges and provide homes for hermit crabs, prawns and the extremely common squat lobster (Munida sarsi) while urchins, sea cucumbers (Stichopus tremulus) and brittle stars are regularly seen on the seabed.
This visit was a very sucessful trial of the use of drilling rigs and their ROV support for science. It would not have been possible without the help and support of the industrial collaborators BP, Transocean and Subsea7 and also the help of everyone on the PBLJ particularly the ROV crew.
Please contact Daniel Jones for more details about this project.