The Hewett gas field is a large natural gas and associated condensate field located under the North Sea 19 miles (30 km) off the Norfolk coast.
The field
The Hewett gas field is a
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 ...
field located in the UK North Sea. The field is named after the Hewett Ledges a sand bank feature beneath which the field is situated.
The gas reservoir is a Lower
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...
(Middle and Lower Bunter) sandstone and a Permian
Zechstein
The Zechstein (German either from ''mine stone'' or ''tough stone'') is a unit of sedimentary rock layers of Middle to Late Permian (Guadalupian to Lopingian) age located in the European Permian Basin which stretches from the east coast of Englan ...
carbonate bed at a relatively shallow depth of 3,000–4,200 feet (914–1,280 m). The Hewett structure runs north-west to south-east and is about 18 miles long and 3 miles wide (29 km by 4.8 km). It was discovered in October 1966 and extends over blocks: 48/28, 48/29, 48/30, 52/4 and 52/5. To the north are the Big Dottie, Little Dottie and Deborah accumulations, which are separate from Hewett, but are produced through the Hewett topsides facilities. The original determination of the gas in place amounted to 115 billion cubic metres.
The field was originally licensed to
Phillips Petroleum Exploration UK Ltd (then from 2001
Tullow Oil
Tullow Oil plc is a multinational oil and gas exploration company founded in Tullow, Ireland, with its headquarters in London, United Kingdom. The company is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index.
His ...
UK Ltd and from 2008 Eni UK Ltd). Production from the field began in July 1969. Gas and associated condensate are exported from the field via two 30 inch diameter pipelines to the
Bacton gas terminal
The Bacton Gas Terminal is a complex of six gas terminals within four sites located on the North Sea coast of North Norfolk in the United Kingdom. The sites are near Paston and between Bacton and Mundesley; the nearest town is North Walsham.
T ...
, Norfolk. Eni submitted plans in 2019 to decommission the Hewett field and to remove all installations.
The end of production is scheduled for late 2021.
The Hewett gas compositions and properties are as follows.
Development
The Hewett field has been developed through a number of offshore installations.
Production
The annual gas production from the Hewett field (in million standard cubic feet) was:
Decommissioning
In 2020 Eni submitted to the UK Government a proposal for the decommissioning of the Hewett field and its installations. Production from Hewett ceased in 2021.
See also
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Indefatigable gas field
The Indefatigable gas field is a large natural gas and associated condensate field located under the North Sea 60 miles (98 km) off the Norfolk coast.
The field
The indefatigable gas field is a natural gas field located in the North Sea. The fi ...
*
Leman gas field
The Leman gas field is a natural gas field located in the North Sea.The field is north-east of Great Yarmouth and is named after the Leman Sandbank beneath which it is situated. The gas reservoir is an thick Rotliegendes sandstone reservoir at a ...
*
West Sole gas field
The West Sole gas field is a natural gas and associated condensate field located under the North Sea 44 miles (70 km) off the East Yorkshire coast. The field produced Britain’s first offshore natural gas in 1967.
The field
The West Sole gas ...
*
Viking gas field
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 ...
References
{{reflist
Natural gas fields in the United Kingdom
North Sea energy