Arthurian gas fields

Arthurian gas fields
CountryUnited Kingdom
RegionSouthern North Sea
Location/blocksQuadrant 48, 49, 53
Offshore/onshoreOffshore
OwnerMobil (initially)
Field history
Discovery1967 - 2003
Start of production1989
Production
Producing formationsRotliegendes sandstone

The Arthurian gas fields are small natural gas producing areas in the UK sector of the southern North Sea, their names are associated with the legend of King Arthur. The fields started gas production from 1989 and several are now depleted and have been decommissioned.

The fields

Mobil instigated the field naming convention using characters, people, places and objects associated with the legendary British King Arthur. Mobil applied it to its gas fields across the southern North Sea. The Arthurian fields span Quadrants 48, 49 and 53 from Arthur in the south east to Excalibur in the north west.[1]

The Arthurian fields and the reservoir parameters are as follows.[1] [2] [3] [4]

Arthurian fields reservoir parameters
Field Block Coordinates Gas reservoir Gas reserves (see note below) Discovered Original licensee(s)
Arthur 53/2b 53/1d 53.032447 2.390328 3.7 bcm 2003 ExxonMobil
Avalon 49/09b 104 bcf December 1989 Mobil
Camelot North 53/1a Lower Permian Leman sand Rotliegendes 2.30 bcm November 1967 Mobil North Sea Ltd
Camelot Central South 53/1a 7.20 bcm June 1987 Mobil North Sea Ltd
Camelot North East 53/2 52.972000 2.21444 Permian 0.90 bcm March 1988 Mobil North Sea Ltd
Excalibur 48/17a

48/18a

53.465083 1.344583 Rotliegendes 7.1 bcm 1988 Mobil North Sea Ltd
Galahad 48/12 53.546722 1.360611 153 bcf Mobil
Gawain 49/29a 53.171136 2.701406 Leman sands 196 bcf 1970 ARCO
Guinevere 48/17b 53.414833 1.273639 Permian 2.07 bcm 1988 Mobil North Sea Ltd (25.5%)
Lancelot 48/17a 48/18a 53.41002 1.375306 Permian 5.60 bcm 1986 Mobil North Sea Ltd
Malory 48/12d 5.543611 1.244167 Rotliegendes 35 bcf 1997 Mobil
Mordred 48/12b Superior
Tristan 49/29b Permian 0.80 bcm May 1976 Mobil (60%)
Tristan NW 49/29 Granby

Note: bcm = billion cubic metres, bcf = billion cubic feet

Developments

The fields were developed with an array of platforms and subsea completions. Production from the fields was principally routed via existing infrastructure to the onshore Bacton gas terminal.[1] [4] [5] [6] [7] [8]

Arthurian fields offshore installations
Field Water depth, metres Field installations Export to Export pipeline, length and diameter (inches) Production started Decommissioned Current or last operator
Arthur 42 3 Subsea wells Thames 49/28A 18.2 miles, 12” 2005 2014 Esso
Avalon (developed as Windermere) 35 Fixed steel Markham 6.8 km, 8" April 1997 April 2016 Ineos
Camelot North 15 Fixed steel CA Leman 27A 9 miles, 12” October 1989 2011 ERT, Perenco
Camelot Central South 15 October 1989 2011 Perenco
Camelot North East 43 Fixed steel CB Camelot CA 1 mile, 6” December 1992 2002 (reused)
Excalibur 27 Fixed steel EA Lancelot 5 miles, 12” October 1989 2017 Perenco
Galahad 20 Fixed steel monotower Lancelot 16 km November 1995 Operational Perenco, Chieftan, Premier Pict
Gawain 37 Subsea Thames 49/28A 9.6 miles, 12” October 1986 2014 Perenco
Guinevere 17 Fixed steel Lancelot 4 miles, 8” June 1993 Yes Perenco
Lancelot 21 Fixed steel Bacton 40 miles, 20” (LAPS) June 1993 Operational Perenco
Malory 21 Fixed Steel Tee on Galahad -Lancelot pipeline 10” October 1998 Operational Perenco
Mordred 20 Subsea well Galahad
Tristan 37 Subsea drilled from Welland Welland & Thames Nov 1992 2014 Silverstone
Tristan NW Subsea well Davy 15.5 km, 6” 2008 2010 Granby, Silverstone

The pipeline from Lancelot to Bacton is known as the LAPS pipeline (Lancelot Area Pipeline System).[1]

The Lancelot installation also provided an export route for gas from the Durango and Waveney fields.[7] [8] [9]

Field Waveney Durango
Block 48/17c 48/21
Installation Fixed steel platform Subsea wellhead
Water depth, metres 23
Operator ARCO then Perenco Bridge North Sea Ltd
Reservoir Rotliegend Rotliegend
Gas reserves, billion cubic feet 84
Production start 1998 2008
Export to Lancelot Waveney
Pipeline, length and size 7.65 km, 10-inch 14.7 km, 6-inch
Pipeline number PL1639 PL2555

Production

The peak and cumulative production of gas from the Arthurian fields was as follows.[1] [9]

Arthurian fields peak and cumulative gas production
Field Peak production, bcm per year Peak year Cumulative production to 2014, million cubic metres (mcm)
Arthur 0.858 2005 2,378
Camelot North 0.20 1990 921
Camelot Central South 0.60 1990 6,015
Camelot North East 0.10 1993 498
Excalibur 0.53 1994 6,449
Galahad 0.707 1997 4,579
Gawain 0.929 1996 6,311
Guinevere 0.27 1994 2,728
Lancelot 0.93 1993 8,640
Malory 0.668 1999 4,045
Tristan 0.20 1992 1,062
Tristan NW 0.026 2008 45
Windermere (formerly Avalon) 0.438 1998 2,112

The gas production profile from Camelot Central South (in mcm) was as follows:[9]

The gas production profile from Lancelot (in mcm) up to 2014 was as follows:[9]

The gas production profile from Excalibur (in mcm) up to 2014 was as follows:[9]

The gas production profile from Gawain (in mcm) up to 2014 was as follows:[9]

See also

References

  1. ^ a b c d e Department of Trade and Industry (1994). The Energy Report. London: HMSO. ISBN 0115153802.
  2. ^ "Camelot gas fields". abarrelfull.wikidot.com. Retrieved 21 November 2021.
  3. ^ "Lancelot complex gas fields". abarrelfull.wikidot.com. Retrieved 21 November 2021.
  4. ^ a b "The Gawain gas field". Retrieved 21 November 2021.
  5. ^ "Multiple platforms facing removal after cessation at North Sea gas complex". 11 February 2015. Retrieved 21 November 2021.
  6. ^ "Gawain field decommissioning" (PDF). Retrieved 21 November 2021.
  7. ^ a b "Perenco UK SNS Environmental Statement 2019" (PDF). Retrieved 21 November 2021.
  8. ^ a b "Oil & Gas Authority installations". Retrieved 21 November 2021.
  9. ^ a b c d e f "Oil and gas field data". 6 October 2016. Retrieved 22 November 2021.