Bow said Depco Drilling's coring rig moved to Orallo South-1 earlier in the week to re-enter the hole, which was suspended in April due to unsatisfactory drilling operations by the previous drilling contractor.

At 6am local time today, the current depth of the well was 460m and was drilling ahead to a revised total depth of 550m, the company added.

Orallo South-1 is designed to determine the Walloon Coal Measures thickness and gas contents required for the Don Juan joint venture reserves certification program.

Following completion of Orallo South-1, the rig will move to the Carnarvon-4 exploration core hole.

The Don Juan CSM partners are Bow (55%) and Victoria Petroleum (45%).