ConocoPhillips has paused drilling operations at the Charlemont-1 exploration well in the Otway basin offshore Australia after encountering gas significantly earlier than anticipated. The well intersected significant gas shows in the Waarre C reservoir approximately 160 metres above the primary target, the Waarre A reservoir. This occurrence was unexpected, as the pre-drill evaluation did not predict gas at this shallower depth of 2552 metres, and the pressures encountered were higher than forecast.

Operational Response and Well Details

Drilling is temporarily halted while the operator evaluates potential adjustments to the well design, including options to proceed to the primary target. The Charlemont-1 well, located 55 kilometres offshore Port Campbell in 110 metres of water, was spudded on 10 December using the Transocean Equinox rig. It was initially planned to drill to a depth of 2830 metres over 32.9 days, targeting a gross mean prospective resource of 93 billion cubic feet in the Waarre A reservoir.

Program Context and Risks

This is the second consecutive wildcat in ConocoPhillips' Otway exploration drilling programme, following the Essington-1 well drilled in November. The full programme includes a first phase of up to six exploration wells in the Vic/P79 permit. A potential second phase comprises up to four additional optional wells in the T/49P permit, contingent on the outcomes of the first phase. Prior to drilling, technical risks for Charlemont-1 were identified, including potential fault seal leakage that could reduce gas saturation, and elevated carbon dioxide concentrations associated with deep-seated fault systems.

Partnership Structure

The joint venture partners in the Vic/P79 permit are operator ConocoPhillips (51% interest), Korea National Oil Corporation (29%), and 3D Energi (20%).