"While recognising this well is only the first in our WA-390-P Permit, the result is very encouraging," president of exploration and production John O'Connor said.

Glencoe-1, the first of four exploration wells the company is drilling on the permit this year, was drilled in 1121m of water by the semi-submersible rig Jack Bates.

Following the completion of the Glencoe-1 well, the Jack Bates rig will move 14km east to drill Briseis-1, which will test a separate structure.

Hess has a 100% interest in the 780,000-acre permit, which it secured last year with a 16-well drilling commitment that set new Australian work and financial obligation records.

WA-390-P is next to the giant Jansz/Io discovery, held by the Gorgon partners, Chevron Australia, Shell Development Australia and ExxonMobil, and due west of the Greater Gorgon gas field.