Marquis has a mid-case reserves estimate of about 143 million barrels if hydrocarbons are present. Elixir estimates it has about a one-in-three chance of a commercial find.

The 21/6b-6 well was spudded on Saturday by the Bredford Dolphin semisubmersible drilling rig and is operated by farminee Century Exploration (UK) Limited.

“The well has a planned total depth of 2,000m and is prognosed to take around 18 days to drill,” Elixir said.

“The primary objective, the Palaeocene Forties-Balmoral sands, is interpreted to be reached at a depth of approximately 1,600m or around Day 12 in the drilling program. The well is being drilled as a low-cost finder well and will not be flow tested.”

Elixir, which is listed on both the Australian Stock Exchange and London's Alternative Investment Market, has a 15% interest in Block 21/6b. It is contributing 10% of the Marquis well’s estimated total cost of about £3.7 million (A$8.9 million).