ConocoPhillips has achieved exploration success with the Charlemont-1 wildcat in the Otway basin offshore Australia, its second well in the current campaign. The well, targeting the Charlemont B Prospect in permit VIC/P79, intersected probable hydrocarbons across three Waarre sandstone formations (A, B, and C). This result is significant as gas was not anticipated in the Waarre C formation prior to drilling.

Operational Details and Evaluation

Drilling at Charlemont-1 was paused after unexpectedly intersecting gas in the Waarre C zone above the primary target. Operations resumed with a modified well design but were concluded prior to the planned total depth after encountering higher-than-anticipated formation pressures at 2753 metres. Elevated gas readings were recorded across the Waarre A, B, and C sandstone intervals. Further wireline logging is required to evaluate the nature, extent, and potential connectivity of the hydrocarbons in these reservoirs. Operations and formation evaluation are ongoing and likely to finish at the end of January 2026, with evaluation results expected by the end of the current month.

Commercial and Development Implications

The presence of gas in all three Waarre reservoirs de-risks up-dip prospects on the Charlemont trend. If successfully appraised, this cluster could be among the largest gas pools in the Otway basin. A preferred development concept is already being considered, involving two operators with nearby facilities who have expressed interest in processing the gas. The joint venture partners must integrate the results of Charlemont-1 and the earlier Essington-1 discovery into their geologic model before making commercial decisions. The JV has options for further drilling with the Equinox rig, and a decision on a subsequent well is pending.

Exploration Programme Context

The current Otway exploration drilling programme includes a first phase of up to six exploration wells in the Vic/P79 permit, where ConocoPhillips is operator with a 51% interest, partnered with Korea National Oil Corporation (29%) and 3D Energi (20%). A second phase of up to four optional wells in the T/49P permit is contingent on the outcomes of the first phase.