The Greater Markham Area gas fields are
natural gas
Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...
reservoirs and gas production facilities that straddled, or are close to, the UK and Netherlands median line of the southern
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea, epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the ...
. 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
Ultramar is an Eastern Canadian gas and home fuel retailer, with its head office located in Montreal, Quebec. Ultramar operates gas stations and home fuel delivery in Ontario, Quebec, and Atlantic Canada.
History
British oil company Ultramar ...
in July 1984 with well 49/05-2. It is a lower
Permian
The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last ...
Leman/Slochteren sandstone, sourced from
Carboniferous coal measures and is overlaid with Permian Silverpit claystone. It is a sweet gas with 83 %
methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Ea ...
and a gas/condensate ratio of 9 barrels per million standard cubic feet (9 bbl/MMSCF) or 52.2 m
3/10
6 m
3. Recoverable reserves were estimated to be 700 Billion cubic feet (BCF) or 19.8 x 10
9 m
3.
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 CH
4 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
The Rotliegend, Rotliegend Group or Rotliegendes (german: the underlying red) is a lithostratigraphic unit (a sequence of rock strata) of latest Carboniferous to Guadalupian (middle Permian) age that is found in the subsurface of large areas in wes ...
-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 x 10
6 m
3.
Chiswick, Grove and Kew
The Chiswick and Kew are both Carboniferous fields Chiswick has gas in place of 687 BCF or 19.45 x 10
6 m
3 and Kew 85 BCF or 2.41 x 10
6 m
3.
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.
The Chiswick, Grove, Kew and Stamford gas fields were developed over the period 2006-2014 by four offshore installations, detailed in the table.
In addition to the platforms and subsea wells there were also gas and methanol pipelines and umbilicals in the Greater Markham area.
Production
Gas production from Greater Markham Area fields is shown in the table and the graphs.
The production profile, in mcm/y, of the Markham field was as shown.
The production profile, in mcm/y, of the Windermere field was as shown.
The production profile, in mcm/y, of the Chiswick field was:
The production profile, in mcm/y, of the Grove field was:
The production profile, in mcm/y, of the Kew field was:
The production profile, in mcm/y, of the Stamford field was:
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
This list of oil and gas fields of the North Sea contains links to oil and natural gas reservoirs beneath the North Sea. In terms of the oil industry, "North Sea oil" often refers to a larger geographical set, including areas such as the Norwegi ...
*
Minke, Orca, Sillimanite and Wingate gas fields
References
{{reflist
North Sea energy
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea, epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the ...
Natural gas fields in the Netherlands
Natural gas fields in the United Kingdom