ConocoPhillips, in collaboration with partner 3D Energi, has commenced drilling at the Essington-1 gas exploration well in the Otway Basin, Victoria, Australia.
This drilling, part of the Otway exploration drilling programme (OEDP), aims to explore natural gas reserves for the East Coast market.
The Transocean Equinox rig began operations on 1 November 2025 within the VIC/P79 exploration permit, located 55km offshore from Port Campbell.
Essington-1 is targeting a combined 262 billion cubic feet (bcf) of mean prospective resources within the Waarre C and Waarre A reservoirs.
The Waarre C reservoir, located at around 2,240m true vertical depth subsea (TVDSS), has a 76% chance of success and an estimated 76bcf of resources.
Waarre A, the primary target, lies at around 2,470m TVDSS and is believed to contain 186bcf of resources, with a 68% chance of success.
Direct hydrocarbon indicators support the presence of hydrocarbons in these reservoirs.
The drilling of Essington-1 is expected to last around 32 days, reaching a total depth of 2,650m TVDSS, subject to operational conditions.
3D Energi executive chairman Noel Newell said: “This marks the beginning of the Otway exploration drilling programme, one of the most exciting exploration campaigns on Australia’s East Coast in recent years.
“Essington-1 is testing stacked gas reservoirs that have the potential to transform our resource base and help underpin the future energy needs of the East Coast’s domestic gas supply.
“It is a major milestone for 3D Energi, and just the start of what promises to be an exciting drilling programme for shareholders.”
Upon completion, further evaluation including wireline logging will assess the hydrocarbon presence and reservoir quality.
Potential technical risks include fault seal leakage and high CO₂ concentrations.
Essington-1 is the first of two wells planned in the initial phase of the OEDP.
The programme aims to identify commercially viable gas reserves, with a proposal to drill up to six wells in total.
Upon completion of Essington-1, the Transocean Equinox rig will move to drill the Charlemont-1 exploration well, located 20km north-west within the same permit area.
