The Thames gas field is a depleted natural gas reservoir and former gas production facility in the UK sector of the southern North Sea. The field is located about 80 km north east of Bacton, Norfolk; the Thames production facility was in operation from 1986 until 2014.

The fields The Thames field was discovered by ARCO in December 1973 by well 49/28-4. The field is principally located in Block 48/28. The gas reservoir is a Rotliegend sandstone. At the time of start-up, the field was jointly owned by ARCO British Ltd (43.34%), British Sun Oil Co Ltd (23.33%), Superior Oil (UK) Ltd (20.00%), Deminex UK Oil & Gas Ltd (10.00%), and Canadian Superior Oil (UK) Ltd (3.33%). The field was anticipated to have recoverable reserves of 16.2 billion cubic metres (bcm).

In addition to Thames, the adjacent fields produced natural gas to the Thames facility. +Thames area fieldsFieldBlockDate discoveredReserves, bcm (note 1)Original ownerOwner in 2014Thames49/28December 197316.2ARCO & othersPerencoBure49/28May 1983Wensum49/28September 1985Yare49/28May 1969Orwell50/26aFebruary 19906.9ARCO/ TexacoTullowDeben49/281.0TullowTullowWelland NW53/4aJanuary 19848.1ARCO/Britoil/ElfPerencoWelland S53/4aJune 1984Arthur53/220033.7ExxonMobilPerencoGawain49/29a19705.55ARCOPerencoHorne53/31992Hamilton OilTullowWren53/31997ARCOTullowWissey53/041967Signal OilTullow note 1. Reserves are in billion cubic metres (bcm).

The Thames, Bure, Deben, Welland, Wensum and Yare fields are named after rivers in East Anglia and south east England.

Arthur and Gawain are part of the Arthurian gas fields.

Development The Thames field was developed by ARCO as a central 3-platform bridge linked complex. In addition to its own gas, Thames was designed to be a central hub to receive and process well fluids from the surrounding installations. Processed gas was transmitted by pipeline from Thames to the Bacton Gas Terminal, Norfolk. The main design parameters of the Thames area installations are summarized in the table. +Thames area installationsInstallation nameBlockCoordinatesWater depth, metresTypeLegsPilesWell slotsProduction toPipeline, length and diameterPipeline numberThames AP49/2853°05’02”

02°32’50”31Steel jacket66NilThames AWbridge–Thames AW49/2853°05’04”

02°32’50”31Steel jacket445Bacton89.5 km, 24”PL370Thames AR49/2853°05’02”

02°32’53”31Vierendeel tower44nilThames APbridge–Horne/Wren53/352°54’06”

02°35’57”41Steel jacket2Thames AR20.3 km 10”PL2080Bure O49/28-853°07’25”

02°25’32”35Subsea wellhead––1Thames AW9.3 km, 8”PL371Bure West49/28-1853.129177 02.40361435Subsea wellhead––1Thames AR11.2 km, 8”PL1635Orwell49/26a253°08’28” 03°02’34”33Subsea wellhead––3Thames AW34 km, 16”PL931Yare C49/2853.044933

2.57423137Subsea wellhead––Thames AW4.8 km, 8”PL372Welland49/29b53.985194 02.73659439Steel jacket31Thames AW17.5 km,16”PL674Welland NW49/29b53.089044 2.67514734Subsea wellheads––3Welland8 km, 5.8 km, 3.2 km, 8”PL676  PL677

PL678Arthur53/252°54’48”

02°14’57”42Subsea wellhead––3Thames AW29.3 km, 12”PL2047Gawain49/29a53°09’35” 02°44’06”37Subsea wellhead––1Thames AW15.4 km, 12” PL1057Deben / Thurne49/2853°06’03”

02°28’44”34Subsea wellhead––Thames AR5.2 km, 8”PL1637Wissey53/4d52°54’05” 02°45’11”39Subsea wellhead––Horne/Wren30.9 kmPL2492

In 2007 the Deben wellhead was reused for the Thurne development.

The Thames AP platform had the main process equipment which included gas compressors and liquid handling plant. The accommodation facilities for 47 crew were also located on AP. The AW platform had 5 wellheads and the reception facilities for Arthur, Orwell, Gawain, Bure, Welland and Yare fields. The AR platform had reception facilities for Bure West, Horne/Wren and Thurne fields.

In addition to the gas pipelines, there were also umbilicals between some of the installations. +UmbilicalsNameFrom – toDiameter, inchesLength, kmPipeline numberYare C umbilicalThames AW to Yare C well44.8PL373Bure O umbilicalThames AW49.3PL374Bure West umbilicalThurne to Bure West511.2PL1636Thurne flowlineThames AR to Thurne84.6PL1637Thurne umbilicalThames AR to Thurne54.5PL1638

As part of the Thames development new pipeline reception facilities and process plant was installed at the Phillips (latter Eni, Tullow) terminal at Bacton gas terminal. From the reception facilities gas passed to the former Amoco (later Perenco) site for treatment.

Gas production Gas production from Thames and the connected fields is shown in the table, data includes the peak rate and the cumulative production over the period 1986 to 2014. +Gas ProductionNameProduction startPeak flow, mcm/yPeak yearProduction endCumulative production to 2014Thames19861,600198720146,867Wensum1986199761Yare198620141,945Bure O1986291198820142,003Bure West19862014822Horne2005325200620111,238Wren2005396200720121,045Orwell19931,470199520088,618Welland NW1990931199120025,378Welland South1991389199220022,283Arthur2005858200520142,378Gawain1995929199620146,311Deben199824019992004457Thurne200712920072012209Wissey200825720092013574

Decommissioning and recommissioning A cessation of production authorisation for Thames was granted in May 2014. Perenco developed a decommissioning programme. This entailed the plugging and abandonment of all wells and removal of all structures above the seabed. Pipelines were left in situ after being flushed and filled with seawater.

In 2019 Independent Oil and Gas (now IOG) purchased the Thames gas pipeline reception facilities at the Bacton terminal. The facilities comprise an area of land within the Perenco part of Bacton where IOG’s fully owned Thames pipeline connects to the terminal. It includes gas and liquids reception equipment recommissioned for the development of IOG’s southern North Sea Core Project, across six fields. Produced gas will continue onto the main Perenco Bacton plant for final processing. In 2021 the Blythe and Southwark platforms were installed.

See also

Bacton gas terminal Arthurian gas fields Leman gas field Indefatigable gas field List of oil and gas fields of the North Sea

References