Magnus oilfield
Encyclopedia
The Magnus oilfield is a large oilfield in the United Kingdom
's zone of North Sea
. It is located 160 kilometres (99.4 mi) north-east of the Shetland Islands
. The field is located mainly in Block 211/12a. Resources are estimated to total 1.54 Goilbbl of oil, of which 869 Moilbbl are recoverable reserves.
. The discovery was made 2709 metres (8,887.8 ft) below the seabed in the younger sands of the Late Jurassic
by the semi-submersible
drilling rig
Sedco 703. Similarly to several other fields in the area, the field was named after the Viking saint–Magnus of Orkney.
Fabrication of the Magnus structure began in 1980 at Highland Fabricators' yard at Nigg Bay
in the Cromarty Firth. The jacket of the Magnus platform, the main oil export pipeline to the Ninian Central Platform
, and the Northern Leg Gas Pipeline
to Brent A
were installed by 1982.
In May 1996, the production started at the South Magnus field. First oil from the field was achieved in August 1983.
The enhanced oil recovery
project was proposed in 2000. It was implemented in 2003.
. The Magnus jacket is the largest single piece steel structure in the North Sea. It was designed, manufactured and installed by John Brown Offshore. The original system also included seven subsea producing wells which were later turned around to water injection duty.
The produced oil is transported by a 91 kilometres (56.5 mi) long 24 inches (609.6 mm) pipeline to the Ninian Central platform, and further to the Sullom Voe Terminal
. Produced natural gas from Magnus, together with gas from the Thistle and Murchison fields, is transported by a 79 kilometres (49.1 mi) long 20 inches (508 mm) pipeline to Brent A and further through the FLAGS
to St Fergus in Aberdeenshire
.
and Schiehallion
to the Sullom Voe terminal where liquefied petroleum gas is added to natural gas. This gas stream is then transported by another pipeline to the Magnus platform where it is reinjected into the Magnus reservoir to aid pressure support and increased oil recovery. It is expected to increase the recoverable oil reserves by 50 Moilbbl and extend the field life to beyond 2015. The project cost around £320 million.
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
's zone of North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
. It is located 160 kilometres (99.4 mi) north-east of the Shetland Islands
Shetland Islands
Shetland is a subarctic archipelago of Scotland that lies north and east of mainland Great Britain. The islands lie some to the northeast of Orkney and southeast of the Faroe Islands and form part of the division between the Atlantic Ocean to the west and the North Sea to the east. The total...
. The field is located mainly in Block 211/12a. Resources are estimated to total 1.54 Goilbbl of oil, of which 869 Moilbbl are recoverable reserves.
History
The Magnus oilfield was discovered in March 1974 by BPBP
BP p.l.c. is a global oil and gas company headquartered in London, United Kingdom. It is the third-largest energy company and fourth-largest company in the world measured by revenues and one of the six oil and gas "supermajors"...
. The discovery was made 2709 metres (8,887.8 ft) below the seabed in the younger sands of the Late Jurassic
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...
by the semi-submersible
Semi-submersible
A semi-submersible is a specialised marine vessel with good stability and seakeeping characteristics. The semi-submersible vessel design is commonly used in a number of specific offshore roles such as for offshore drilling rigs, safety vessels, oil production platforms and heavy lift cranes.The...
drilling rig
Drilling rig
A drilling rig is a machine which creates holes or shafts in the ground. Drilling rigs can be massive structures housing equipment used to drill water wells, oil wells, or natural gas extraction wells, or they can be small enough to be moved manually by one person...
Sedco 703. Similarly to several other fields in the area, the field was named after the Viking saint–Magnus of Orkney.
Fabrication of the Magnus structure began in 1980 at Highland Fabricators' yard at Nigg Bay
Nigg Bay
Nigg Bay is a large relatively shallow sandy bay, consisting of mudflat, saltmarsh and wet grassland, located at the north east coast of the Cromarty Firth and is 5 miles to the east of Invergordon, in the district of Ross and Cromarty and is in the Scottish council area of Highland.During low...
in the Cromarty Firth. The jacket of the Magnus platform, the main oil export pipeline to the Ninian Central Platform
Ninian Central Platform
The Ninian Central Platform is an oil platform in the North Sea. When constructed in Loch Kishorn, Scotland in 1978 the 600,000 tonne platform was the world's largest man-made movable object before being towed to its current position and fixed to the sea floor.It is a circular concrete gravity...
, and the Northern Leg Gas Pipeline
FLAGS
The FLAGS pipeline is a natural gas pipeline in the North Sea which is used to transport liquids and associated gas from the following fields:* Cormorant A* North Cormorant* North West Hutton...
to Brent A
Brent oilfield
The Brent field is an oil field located in the East Shetland Basin north-east of Lerwick, Shetland Islands, Scotland at the water depth of . The field operated by Shell UK Limited was once one of the most productive parts of the UK's offshore assets but is now nearing the end of its useful...
were installed by 1982.
In May 1996, the production started at the South Magnus field. First oil from the field was achieved in August 1983.
The enhanced oil recovery
Enhanced oil recovery
Enhanced Oil Recovery is a generic term for techniques for increasing the amount of crude oil that can be extracted from an oil field...
project was proposed in 2000. It was implemented in 2003.
Reserves
Magnus field's reserves are estimated to contain 1.54 Goilbbl of oil, of which 869 Moilbbl are recoverable reserves.Technical description
The field is developed by a single central combined drilling and production platformOil platform
An oil platform, also referred to as an offshore platform or, somewhat incorrectly, oil rig, is a lаrge structure with facilities to drill wells, to extract and process oil and natural gas, and to temporarily store product until it can be brought to shore for refining and marketing...
. The Magnus jacket is the largest single piece steel structure in the North Sea. It was designed, manufactured and installed by John Brown Offshore. The original system also included seven subsea producing wells which were later turned around to water injection duty.
The produced oil is transported by a 91 kilometres (56.5 mi) long 24 inches (609.6 mm) pipeline to the Ninian Central platform, and further to the Sullom Voe Terminal
Sullom Voe Terminal
The Sullom Voe Terminal is an oil and liquefied gas terminal at Sullom Voe in the Shetland Islands of Scotland. It handles production from oilfields in the North Sea and East Shetland Basin...
. Produced natural gas from Magnus, together with gas from the Thistle and Murchison fields, is transported by a 79 kilometres (49.1 mi) long 20 inches (508 mm) pipeline to Brent A and further through the FLAGS
FLAGS
The FLAGS pipeline is a natural gas pipeline in the North Sea which is used to transport liquids and associated gas from the following fields:* Cormorant A* North Cormorant* North West Hutton...
to St Fergus in Aberdeenshire
Aberdeenshire
Aberdeenshire is one of the 32 unitary council areas in Scotland and a lieutenancy area.The present day Aberdeenshire council area does not include the City of Aberdeen, now a separate council area, from which its name derives. Together, the modern council area and the city formed historic...
.
Enhanced oil recovery project
To increase the recoverable oil from the field and to extend the field life, an enhanced oil recovery (EOR) project was implemented. The EOR project involved importing gas from the two West of Shetland fields FoinavenFoinaven oilfield
Foinaven oil field is deepwater oil development approximately west of the Shetland Islands. Together with Schiehallion, Loyal and Clair fields it forms the area generally termed as the West of Shetland.-Field description:...
and Schiehallion
Schiehallion oilfield
The Schiehallion oilfield is a deepwater offshore oilfield approximately west of the Shetland Islands in the North Atlantic Ocean. The Schiehallion and adjacent Loyal field were jointly developed by BP on behalf of the Schiehallion field partners; BP, Shell, Amerada Hess, Murphy Oil, Statoil and...
to the Sullom Voe terminal where liquefied petroleum gas is added to natural gas. This gas stream is then transported by another pipeline to the Magnus platform where it is reinjected into the Magnus reservoir to aid pressure support and increased oil recovery. It is expected to increase the recoverable oil reserves by 50 Moilbbl and extend the field life to beyond 2015. The project cost around £320 million.