The Greater Markham Area gas fields are natural gas reservoirs and gas production facilities that straddled, or are close to, the UK and Netherlands median line of the southern North Sea. The UK field production facilities, which export gas to the Netherlands, began operation in 1992.
The fields The Greater Markham Area gas fields are located in UK Blocks 49/4, 49/5, 49/9 and 49/10 and in Netherlands Blocks J3 and J6 of the southern North Sea. The fields are named: Markham, Windermere, Chiswick, Grove, Stamford and Kew.
Markham The Markham gas field was discovered by Ultramar in July 1984 with well 49/05-2. It is a lower Permian Leman/Slochteren sandstone, sourced from Carboniferous coal measures and is overlaid with Permian Silverpit claystone. It is a sweet gas with 83 % methane and a gas/condensate ratio of 9 barrels per million standard cubic feet (9 bbl/MMSCF) or 52.2 m3/106 m3. Recoverable reserves were estimated to be 700 Billion cubic feet (BCF) or 19.8 billion m3. Ownership of the gas was established by the UK/Netherlands Markham Treaty as 37.40 % UK and 62.60 % Netherlands.
The original licensee for Markham was a joint venture comprising Ultramar Exploration Ltd (89.50 %), DNO Offshore Ltd (8.00 %) and Ranger Oil (UK) Ltd (2.5 %.). Ownership passed to CH4 Energy Ltd in 2003, Venture Production acquired ownership in 2006. Ownership eventually passed to Centrica, then in 2017 to Spirit Energy a joint venture of Centrica plc and Bayerngas Norge AS.
Windermere The UK Windermere gas field produced gas to Markham and hence to the Netherlands. Windermere is a Rotliegend-Leman sandstone discovered in 1989 by well 49/09b-2 by Mobil (who named the field Avalon) and had an estimated gas in place of 104 BCF or 2.8 million m3.
Chiswick, Grove and Kew The Chiswick and Kew are both Carboniferous fields Chiswick has gas in place of 687 BCF or 19.45 million m3 and Kew 85 BCF or 2.41 million m3.
Development The Greater Markham Area gas fields were developed in stages. Markham and Windermere gas fields were the first to be developed in 1994 and 1996. Gas was produced by two offshore installations, detailed in the table. +Offshore platforms Markham and WindermereInstallationMarkham ST-1WindermereBlocks49/5a and 49/10b (UK),
J3b and J6 (NL)49/9bCoordinates53° 50.527’ N 02° 52.059’ E53° 49.937’ N 02° 46.364’ EOwnerSpirit EnergyIneos UK SNS LtdTypeNormally unattendedNormally unattendedWater depth, metres3135Installation date1994November 1996Jacket typeFixed steelFixed steelJacket legs43Jacket piles43Jacket weight, tonnes888382Topsides dimensions, metres26.3m x 22m30m x 30mTopsides weight, tonnes1,300452Wellheads62Export toMarkham J6-AMarkham ST-1Production startNovember 1992April 1997 The Chiswick, Grove, Kew and Stamford gas fields were developed over the period 2006-2014 by four offshore installations, detailed in the table. +Offshore installations Chiswick, Grove, Kew and StanfordInstallationChiswickGroveKewStamfordBlocks49/4a49/10a49/4c49/10cCoordinates53.939967 2.774053353.858778 2.88600053.954935 2.78448653.804192 2.836928OwnerSpiritSpiritSpiritSpiritTypePlatformPlatformSubsea wellheadsSubsea wellheadsWater depth, metres40304134Installation date2006200620142009Jacket typeFixed steelFixed steel––Jacket legs––Jacket piles––Jacket weight, tonnes650500––Topsides weight, tonnes350480––Wellheads11Export toMarkham J6-AMarkham J6-AChiswickMarkham J6-AProduction start2006200620142009 In addition to the platforms and subsea wells there were also gas and methanol pipelines and umbilicals in the Greater Markham area. +Pipelines and UmbilicalsFrom – ToCountryFluidDiameter, inchesLength, kmPipeline numberMarkham ST-1 – Median lineUKGas122.35PL992Median line – J6ANetherlandsGas123.13PL992J6A – Median lineNetherlandsMethanol23.127PL993Median line – Markham ST-1UKMethanol22.347PL993Windermere – Markham ST-1UKGas86.8PL1273Markham ST-1 – WindermereUKMethanol26.8PL1273.1-3Chiswick – J6A UK, NetherlandsGas1018.3PL2353J6A – ChiswickUK, NetherlandsMethanol1.518.3PL2354Grove – J6AUK, NetherlandsGas1013.4PL2319J6A – GroveUK, NetherlandsMethanol213.4PL2320Stamford – J6AUK, NetherlandsGas67.5PL2367J6A – StamfordUK, NetherlandsMethanol7.5PLU2368Kew – ChiswickUKGas63.1PL2974Chiswick – KewUKMethanol3.1PLU2975
Production Gas production from Greater Markham Area fields is shown in the table and the graphs. +Gas ProductionFieldProduction startPeak flow, mcm/yPeak yearProduction ceasedCumulative production to 2020 (mcm)MarkhamNovember 19929331995April 20167,877WindermereApril 19974381998April 20162217Chiswick20075692009–6915Grove20076362010–3873Kew20141752014–1053Stamford200913220092013165
Decommissioning Spirit Energy submitted a Markham ST-1 decommissioning Programme to the Oil and as Authority in 2018. Ineos Oil & Gas UK submitted a Windermere decommissioning Programme to the Oil and as Authority in 2018. Decommissioning activities entailed plugging and abandonment of the wells and removal of all structures above the seabed. The Markham topsides were taken to Lerwick Shetland for dismantling.
See also
List of oil and gas fields of the North Sea Minke, Orca, Sillimanite and Wingate gas fields
References