Helvellyn was discovered in 1985 and was acquired by MOG in 2001 from BP.
The field has been developed by a single subsea well tied back to the Perenco operated Amethyst A2D platform from where gas is exported to Dimlington.
Gas Production began in February 2004, and 19bcf of gas had been produced up to end 2017. There are estimated remaining reserves of c.1bcf. No further development activity is currently contemplated at Helvellyn.