U.K. oilfield players Star Energy Group and EnCore have agree to expand a gas-storage feasiblity study and financing deal to cover a second and possibly a third depleted U.K. sector gas field, it was undestood Monday.

The Esmond and possibly the Gordon field will be added to the Forbes gas-storage site, in a project that aims to make storage for 150 billion cubic metres of gas, doubling U.K. capacity.

Star Energy decided last year to farm into EnCore’s Block 43/8, Forbes acreage to look at converting the field into a seasonal gas store with up to 50 bcf of working gas capacity.

The bigger study would include EnCore’s Block 43/13a (Esmond) and potentially Blocks 43/15a and 43/20a (Gordon). Star would pay £250,000 ($490,000) toward extending a low-density, 3D seismic survey to include Esmond and mayby Gordon. As with the Forbes deal, the farm-out grant Star up to 50 percent and “operatorship”.

If all goes well, Star will conduct a front-end, engineering and design study and bear the cost of drilling the first well.

Terms demand the study be completed in 2007.