Parts of this article (those related to remaining reserves and ongoing production) need to be updated. Please help update this article to reflect recent events or newly available information.(April 2024)
5.7×10^6 m3/d 200×10^6 cu ft/d 2.1×10^9 m3/a (74×10^9 cu ft/a)
Estimated gas in place
316×10^9 m3 11×10^12 cu ft
The Leman gas field is a natural gas field located in the North Sea 30 miles (48 km) northeast of Great Yarmouth, United Kingdom. Named after the Leman Sandbank beneath which it is situated, the gas reservoir is a 18 miles (29 km) long, 5 miles (8.0 km) wide,[2] 800 ft (240 m) thick Rotliegendes sandstone reservoir at a depth of about 6,000 ft (1,800 m).
Following its discovery in August 1966, the reservoir was divided into blocks 49/26 and 49/27 to facilitate the licensing of mineral rights. Block 49/26 has been licensed to Shell since the beginning, with Block 49/27 originally licensed to the Amoco-Gas Council joint venture before being transferred to Perenco UK Ltd. Production of natural gas and condensates began in 1968, with both products sent via pipeline systems to the Bacton Gas Terminal on the coast of Norfolk for international distribution.
The initial total proven reserves of the Leman gas field were around 11 trillion ft3 (316 km3), with a production rate of around 200 million ft3/day (5.7×105 m3).[3]
Development
The Shell Leman 49/26A (AD1, AD2, AP & AK) installation began production in August 1968. It had initial recoverable reserves of 292 billion m3.[4] It is connected to the Shell terminal at Bacton. Leman 49/26B (BT & BH) and 49/26B (BP & BD) began production in November 1970. Leman 49/26C (CD & CP) began in February 1972. Leman 49/26D began in August 1974. Leman 49/26E started in August 1983. Leman 49/26F and 49/26G began in September 1987. The Leman complex of platforms are connected to Bacton via Leman 49/26A, which is east of the Hewett complex. A decommissioned 36-inch pipeline formerly delivered gas from Leman 49/26BT to Bacton. Gas and condensate is piped to Bacton via Leman 49/26A Complex (AK, AP, AD1 and AD2).
Drilling, production (500 MMSCFD) and accommodation
Steel jacket
12
19
1971/3
September 1974
Leman BT
Leman E platform
49/26
Leman E
Drilling, production (240 MMSCFD) and accommodation
Steel jacket
6
10
January 1982
September 1983
Leman BP
Leman F platform
49/26
Leman F
Drilling, production and accommodation
Steel jacket
Leman AP
Leman G platform
49/26
Leman G
Drilling, production and accommodation
Steel jacket
Leman F
Leman BT BK BH Complex
49/26
Leman BT
Field terminal
Steel jacket
6
–
June 1970
Bacton
Leman BK
Compression (900 MMSCFD)
Steel jacket
8
–
February 1975
1975
Leman BH
Accommodation
Steel jacket
4
–
February 1981
–
–
The Shell Leman 49/26A complex also receives gas from the Corvette CV installation (Block 49/24) via a 36.6 km, 20-inch pipeline.
Block 49/27 of the Leman field is licensed to, and operated by, Perenco UK Ltd, originally by the Gas Council-Amoco. BP took over the interests of Amoco in 1998 and operated as BP-Amoco, subsequently BP. Perenco UK Ltd took over the interests of BP in the Leman and Indefatigable fields and BP plant at Bacton in 2003. The field had initial recoverable reserves of 292 billion m3.[4] It comprises the following installations, platforms and complexes: Leman 49/27A (AD, AP, AC, AQ, AX); 49/27B (BD, BP, BT); 49/27C (CD, CP); 49/27D (DD, DP); 49/27E (ED, EP); 49/27F (FD, FP); 49/27G; 49/27H; and 49/27J. Gas is routed to Bacton via two 30-inch pipelines from Leman 49/27A and Leman 49/27B.
The Leman installations developed by Amoco, now owned by Perenco, were:
Amoco (now Perenco) Leman installations
Installation
Location Block
Platforms
Function
Type
Legs
Well slots
Installed
Production start
Production to
Leman A Complex
49/27
Leman AD
Drilling
Steel jacket
8
12
August 1967
Easter 1969
Leman AP
Leman AP
Production
Steel jacket
6
–
July 1968
Easter 1969
Leman AC
Leman AC
Compression (900 MMSCFD)
Steel jacket
8
–
1975
October 1976
Bacton
Leman AQ
Accommodation
Steel jacket
4
–
March 1984
–
–
Leman AX
Compression (LP)
Steel jacket
1988
1989
Leman AC
Leman B Complex
49/27
Leman BD
Drilling
Steel jacket
8
12
May 1968
Leman BP
Leman BP
Production (171 MMSCFD)
Steel jacket
6
–
August 1968
Leman BT
Field Terminal
Steel jacket
6
–
April 1970
Bacton
Leman C Complex
49/27
Leman CD
Drilling
Steel jacket
8
12
1967
1969
Leman CP
Production (292 MMSCFD)
Steel jacket
6
–
1967
1969
Leman AP
Leman D Complex
49/27
Leman DD
Drilling
Steel jacket
8
12
1972
1973
Leman DP
Production (300 MMSCFD)
Jack up
6
–
1973
1973
Leman BT
Leman E Complex
49/27
Leman ED
Drilling
Steel jacket
8
12
1972
1974
Leman EP
Production (80-90 MMSCFD)
Steel jacket
4
–
1974
1974
Leman AP
Leman F Complex
49/27
Leman FD
Drilling
Steel jacket
8
12
1973
1975
Leman FP
Production (337 MMSCFD)
Jack up
6
–
1975
1975
Leman BT
Leman G platform
49/27
Leman G
Production (300 MMSCFD)
Steel jacket
12
1985
October 1985
Leman BT
Leman H platform
49/27
Leman H
Production (250 MMSCFD)
Steel jacket
4
4
1984
1985
Leman J
Leman J platform
49/27
Leman J
Production (250 MMSCFD)
Steel jacket
4
4
1984
1985
Leman A
The Perenco Leman 49/27A complex also receives gas from the Camelot CA installation (Block 53/1a) via a 14.5 km, 12-inch pipeline.
In the mid-1990s the glycol dehydration facilities of several installations in the Inde and Leman fields was decommissioned. This enabled the installations to become normally unattended installations (NUIs) reducing manning costs and the risks to personnel.
Production
The Leman gas composition and properties are as follows.[5]
Composition
%
Methane
95.05
Ethane
2.86
Propane
0.49
i-butane
0.08
n-butane
0.09
i-pentane
0.03
n-pentane
0.02
Hexanes
0.02
Heptanes plus
0.04
Nitrogen
1.26
Helium
0.02
Carbon dioxide
0.04
Hydrogen sulphide
Nil
Total sulphur
<0.5
Gas gravity
0.585%
Mean condensate content
1.13 bbl/cubic foot
Btu rating
1024 Btu/ cubic foot
The annual gas production from the Shell Leman field (in million standard cubic feet) was:[5]
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.
The annual gas production from the Amoco Leman field (in million standard cubic feet) was:[5]
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.