IOG has a 50% operated working interest in the Nailsworth field, with the remaining 50% interest held by CalEnergy Resources (UK) Limited (CER).

Please see page 10 of the Annual Report 2022 for a statement of reserves & resources.


Nailsworth was discovered by Shell/Exxon in 1987. Two further appraisal wells were drilled in 1989-90 and a further well was drilled by Century Exploration in 2009.


Nailsworth lies 19km north of the Southwark field. Nailsworth is expected to be developed as part of the Saturn Banks Project – Phase 2, with up to three hydraulically stimulated development wells drilled by a jack-up rig through a suitable Normally Unmanned Installation platform, to be linked to the main Saturn Banks Pipeline export route via a new pipeline connection.