Centrica, the oil and gas operator, said yesterday a further appraisal well had been successfully drilled in the Cygnus gas field, which is potentially one of the most significant undeveloped gas fields in UK waters.
Field partner Endeavour Energy UK said yesterday that reserves estimates for Cygnus in the southern North Sea were now as high as 200million barrels of oil equivalent (boe). This is another piece of good news for Britain’s energy industry, coming just a week after EnCore Oil confirmed that fields in the Catcher area in the central North Sea could contain a huge find of possibly up to 300million barrels of oil.
Centrica owns the largest stake in Cygnus – 48.75% – while operator GDF Suez E&P UK has 38.75% and Endeavour 12.5%.
This latest Cygnus well completes the full appraisal of the field within its current field boundary and follows the successful appraisal in March of the first western area well.
Centrica said this second appraisal well in the western part of the field, had achieved a stabilised flow rate of 5,000 boe per day and had confirmed good reservoir characteristics.
It said analysis from discovery wells together with six appraisal wells and 3D seismic evaluations would allow the reserves potential of the field to be assessed as part of full field development planning.
The company said that, following the successful appraisal of the eastern area of Cygnus in 2009, the licence partners were pursuing a revised and optimised field development plan. It added that this would comprise a first phase to include the full development of the eastern area, and a phase two development of the western area. First gas from the eastern area is scheduled for 2013.
Centrica said the Cygnus field partners had also been awarded an exploration licence for the area surrounding Cygnus, which could extend the field farther.
Centrica Energy’s upstream managing director, Aberdeen-based Jonathan Roger, said: “This is potentially one of the most significant undeveloped gas fields in the UK continental shelf. It comes along at a time when developing the untapped potential of the North Sea is critical to UK energy supply security.”
Rene Montaz-Rosset, managing director of GDF Suez E&P UK, said: “In the past 18 months, four appraisal wells have been drilled and all have been successful in meeting and exceeding pre-drill expectations.”