The firm, which bought Aberdeenshire-based Reach Oil & Gas in 2011, acquired the stake in the Trent East field from Perenco.
Pending permission from the UK government, Trap will spend £5 million on drilling and will eventually share the abandonment costs of the well.
Trent East is thought to contain between 35 and 60 billion cubic feet of natural gas.
Finance director David Kemp said Trap planned to re-open the original appraisal well and hoped to prove reserves at the very top of that range. It would then return and complete a sub-sea link to Perenco’s main Trent field in order to recover the gas.
The company is keen to become an operator, and has now bought into three fields where it aspires to carry out the work. Kemp said Trent East will probably be the first.
He said: “It’s an important milestone for us. It will broaden our scope and reach when we look to other deals.”
The company could use its $20 million (£12.7m) debt facility to fund the work, although it may have enough cash from its interest in the Athena field.
Kemp said Trap is also looking to trade some of its North Sea assets as it develops its portfolio.