The Viking gas field is a group of natural gas and associated condensate fields located under the southern North Sea about 85 miles (136 km) from the Lincolnshire coast. The field was in production from 1972 to 2018.
The field
The Viking gas field is a group of natural gas accumulations under the UK North Sea. The field is named after the area of the North Sea beneath which the field is located.[1] The gas reservoir is a Rotliegendes sandstone of Lower to Middle Permian age, at a depth of 9,100–10,200 feet (2,773–3,110 m) with a thickness of 200–500 feet (61–150 m).[2] The Viking structures run north-west to south-east and extend over Blocks 49/12, 49/16 and 49/17.[1] The field was discovered in 1965 and production started in 1972. The original gas in place amounted to 79.3 billion cubic metres.[1] Gas and associated condensate from Viking A and Viking B were both exported via the Viking A field through a 28-inch diameter pipeline to the Viking gas terminal[2] (renamed the Theddlethorpe gas terminal in 1988), Lincolnshire.
The Victor, Victoria and Vixen fields are adjacent to Viking and production from these fields is routed through the Viking offshore facilities.[2]
The Viking and Victor gas compositions and properties are as follows.[2]
Viking and Victor gas properties
Composition
North Viking %
South Viking %
Victor
Methane
89
89
91
Ethane
6
6
3.6
Propane
1.4
1.4
1.0
Carbon dioxide
2
2
2.5
Gas gravity
0.61
0.61
0.604
Mean condensate content
3–6 bbl/million cu ft
3–6 bbl/million cu ft
1.8 bbl/million cu ft
Calorific value
1030 Btu/cu ft
1030 Btu/cu ft
1020 Btu/cu ft
Ownership
The field was originally licensed to Conoco UK Ltd, later ConocoPhillips. In 2019 Chrysaor assumed the ownership of Conoco-Phillips North Sea Assets.[3] In March 2021 Chrysaor Holdings merged with Premier Oil to form Harbour Energy.[4]
Development
The Viking field was developed through a number of offshore installations. These are summarized in the following tables.[1][2][5]
Viking offshore installations
Installation
Location Block
Facility
Function
Type
Legs
Well slots
Installed
Production start
Production to
Viking A complex
49/12
AD platform
Drilling
Steel jacket
8
11
December 1970
August 1972
Viking AP
AP platform
Processing
Steel jacket
8
–
March 1971
August 1972
Theddlethorpe gas terminal
AR platform
Pipeline risers
Steel jacket
6
–
July 1971
1972
Viking AP
AC platform
Compression
Steel jacket
8
–
June 1975
February 1976
Viking AP
FD platform
Drilling
Steel jacket
4
4
July 1975
July 1976
Viking AD
Viking B complex
49/17
BD platform
Drilling
Steel jacket
8
11
May 1972
August 1973
Viking BP
BP platform
Processing
Steel jacket
8
–
June 1972
August 1973
Viking AR
BC platform
Compression
Steel jacket
8
–
June 1975
July 1977
Viking BP
BA platform
Accommodation
Steel jacket
4
–
1992
–
–
Viking CD
49/17
CD platform
Drilling and processing
Steel jacket
6
4
February 1974
December 1974
Viking B
Viking DD
49/17
DD platform
Drilling and processing
Steel jacket
8
4
May 1974
October 1974
Viking B
Viking ED
49/16
ED platform
Drilling and processing
Steel jacket
8
4
October 1974
November 1975
Viking B
Viking GD
49/17
GD platform
Drilling and processing
Steel jacket
6
4
June 1975
July 1977
Viking B
Viking HD
49/17
HD platform
Drilling and processing
Steel jacket
6
4
July 1974
April 1975
Viking B
Viking KD
49/12
KD platform
Production
Steel jacket
3
6
1998
1998
Viking BD
Viking LD
49/17
LD platform
Production
Steel jacket
3
6
1998
1998
Viking BD
Satellite fields
The satellite fields which exported gas via the Viking B complex were:[5]
Installation
Location Block
Facility
Function
Type
Legs
Well slots
Installed
Production start
Production to
Victor JD
49/22
JD platform
Production
Steel jacket
4
8
June 1984
September 1984
Viking BD
Victor JM
49/22
Subsea well
Production
Subsea
–
1995
1995
Victor JM
Victoria SM
49/17
Subsea well
Production
Subsea
–
2008
2008
Viking BD
Vixen VM
49/17
Subsea well
Production
Subsea
–
1
2000
2000
Viking BD
Production
The annual gas production from the Viking field (in millions of standard cubic feet) was:[2]
Graphs are unavailable due to technical issues. Updates on reimplementing the Graph extension, which will be known as the Chart extension, can be found on Phabricator and on MediaWiki.org.
Export from the Viking B field was originally routed to the shore terminal via Viking AR. From 2009 export was re-routed to shore via the LOGGS installation.[5]
Decommissioning
The Viking A field (Viking North) was decommissioned as uneconomical in 1991. The A field platforms (except AR) were removed in 1993–4.[5]
Viking CD, DD, ED, GD & HD ceased production in 2011–15, and were removed in 2017–18.[5]
Theddlethorpe gas terminal was permanently shut-down in August 2018. Production from all connected fields ceased.[5]