UK's Cygnus tagged with 500 bcf-1.2 tcf of gas

July 7, 2010
Further appraisal success has confirmed GDF Suez E&P-operated Cygnus as one of the largest gas fields discovered in the UK North Sea southern gas basin, said Endeavour International Corp., Houston.

By OGJ editors
HOUSTON, July 7
-- Further appraisal success has confirmed GDF Suez E&P-operated Cygnus as one of the largest gas fields discovered in the UK North Sea southern gas basin, said Endeavour International Corp., Houston.

Endeavour said, “Analysis of the results from Cygnus well data combined with seismic data has led to a reserve estimate in the five appraised fault blocks ranging from a low case of 500 bcf to an upside of 1.2 tcf.”

The 44/12a-5 appraisal well achieved a stabilized flow rate of 29 MMscfd of gas from 94 ft of perforations in the Permian Leman reservoir (OGJ Online, Apr. 15, 2010).

In addition, the Department of Energy and Climate Change has awarded Cygnus field participants interest in P1731 covering blocks 44/11b and 44/12b. This new license contains additional fault blocks that form a northerly extension of the Cygnus structure that are yet to be appraised by drilling.

“The additional fault blocks falling mainly in the new license could add material volumes once drilled,” Endeavour added.

Cygnus interests are GDF Suez E&P 38.75%, Centrica 48.75%, and Endeavour 12.5%.

Besides its 12.5% interest in blocks 44/11a and 12a, Endeavour holds 17.24% in blocks 44/11b and 44/12b.