Field partner InterOil revealed on Wednesday that wireline logging from the sidetrack well confirmed a southern extension of the neighbouring Elk-Antelope discovery with 182 vertical meters of dolomite and a vertical gross gas column of about 339 meters.

Sidetrack drilling started in September using Rig 103 owned by fellow well partner Oil Search.

"First, we intersected the top of the reservoir 36 meters higher than the original Antelope-4 penetration," InterOil chief executive Michael Hession said.

"Second,