Transocean rig just days shy of gas drilling search in Australian waters

October 29, 2025, by Melisa Cavcic

ConocoPhillips Australia (COPA), a subsidiary of the U.S.-headquartered energy giant ConocoPhillips, is only days away from hydrocarbon exploration activities in the Otway Basin off the coast of Australia, which will be undertaken by a semi-submersible rig owned by Transocean, an offshore drilling player.

Transocean Equinox rig; Source: Transocean

After securing all required regulatory approvals for the Otway exploration drilling program, the operator booked AHTS vessels from Sea1 Offshore, formerly Siem Offshore, and Transocean’s Transocean Equinox semi-submersible drilling rig to help it find more gas with the Otway project.

Following a weather-related delay, the semi-submersible began activities for Australia’s Beach Energy offshore Victoria during the quarter, with the plug and abandonment of the Geographe 1 and Thylacine 1 wells already completed. The rig will now work for ConocoPhillips before returning for the second phase of the Australian operator’s activity, scheduled for H2 FY26.

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The mobilization of the rig to the Essington-1 gas exploration well in the Commonwealth waters of VIC/P79 is underway, according to ConocoPhillips’ partner, 3D Energi, a Melbourne-based oil and gas exploration player whose subsidiary, TDO, has a 20% interest in both permits.

These drilling operations, scheduled to start on or around Saturday, November 1, 2025, target a combined 262 billion cubic feet (bcf), mean prospective resource in the Waarre C and Waarre A reservoirs, both supported by direct hydrocarbon indicators (DHIs).

This well is expected to take approximately 32 days to drill to a planned total depth (TD) of 2,650 meters true vertical depth sub sea (TVDSS), subject to operational conditions, representing an important step in 3D Energi’s strategy to deliver a new gas supply for Australia’s East Coast market.

While COPA currently holds the remaining 80% stake, the firm recently inked a deal to lower its stake to 51%, with Korea National Oil Corporation (KNOC) assuming a 29% interest.

The rig was previously expected to spud the Essington-1 well in mid-October 2025, followed by Charlemont-1 between November and December 2025.