ConocoPhillips, in partnership with 3D Energi, has begun drilling operations at the Essington-1 gas exploration well located in the Otway Basin off the coast of Victoria, Australia.
The drilling campaign, initiated on November 1, 2025, forms part of the broader Otway Exploration Drilling Program (OEDP) aimed at uncovering new natural gas resources to supply Australia’s East Coast domestic market.
The Essington-1 well lies within the VIC/P79 exploration permit, approximately 55 kilometres offshore from Port Campbell.
The Transocean Equinox drilling rig is conducting the subsea drilling activity, targeting stacked gas reservoirs at depths of roughly 2,240 to 2,470 meters true vertical depth subsea (TVDSS).
The principal reservoirs targeted are the Waarre C and primary Waarre A formations, with combined mean prospective resources estimated at 262 billion cubic feet (bcf) of natural gas.
The Waarre C reservoir, positioned around 2,240 meters TVDSS, holds an estimated 76 bcf of prospective resources with a 76 per cent chance of success, while the primary target Waarre A reservoir at 2,470 metres TVDSS is projected to contain 186 bcf of resources with a 68 per cent success probability.
Direct hydrocarbon indicators identified during pre-drilling analysis support the presence of hydrocarbons in these reservoir formations.
The drilling phase of Essington-1 is expected to extend over approximately 32 days, subject to operational conditions, reaching a total depth target near 2,650 metres TVDSS.
Following this well, the Transocean Equinox rig plans to move within the same permit area to drill Charlemont-1, the second of at least two wells planned in this initial phase of the program.
This exploration campaign represents one of the first significant offshore drilling efforts in the East Coast waters in nearly seven years, as existing gas fields in regions such as the Bass Strait face depletion risks.
The program aims to secure gas supply amid rising demand and potential shortages forecasted for Victoria and the broader eastern Australian market before the end of the decade.
3D Energi holds a 20 per cent interest in the project and benefits from carried drilling costs by ConocoPhillips, which operates with a majority 80 per cent stake in the permits.
3D Energi’s executive chairman, Noel Newell, described Essington-1 as a milestone, highlighting the potential for these stacked reservoirs to transform the resource base supporting the future energy needs of the East Coast’s domestic gas market.
The program operates under stringent environmental oversight, with all necessary regulatory approvals secured from Australia’s National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA).
The Environmental Plan for the drilling program was approved in February 2025, ensuring responsible operations to minimise marine impact.
This renewed exploration initiative reflects ConocoPhillips and partners’ commitment to addressing Australia’s energy transition by bolstering domestic natural gas resources.
Natural gas remains a critical component in ensuring affordable, reliable energy during the transition towards lower emissions and carbon neutrality.
