US major ConocoPhillips (NYSE:COP, ETR:YCP) has made a significant gas find at the Essington-1 exploration well in the Otway Basin offshore Victoria, with early results pointing to two substantial gas-charged Waarre reservoirs and sparking a sharp rally in junior partner 3D Energi Ltd (ASX:TDO).
Essington-1, in the VIC/P79 exploration permit about 50 kilometres offshore and 12 kilometres from existing gas production wells, was spudded at 3:15am AEST on November 1, 2025, by the Transocean Equinox rig. The 8½-inch hole section penetrated both the primary Waarre A and secondary Waarre C targets and reached total depth of 2,735 metres MDRT safely and without incident.
Wireline logging and pressure data indicate gas-bearing intervals in both reservoirs broadly in line with pre-drill expectations. In the primary Waarre A sandstone, 3D Energi reports a gross gas-bearing interval of 62.6 metres, including 58.5 metres of interpreted net pay. In the secondary Waarre C sandstone, logs point to a gross gas-bearing interval of 33.2 metres, including 31.5 metres of net pay.
Elevated gas readings in both intervals coincided with increased resistivity on logging-while-drilling tools, consistent with hydrocarbon presence. A clear gas gradient identified in formation pressure data provides further evidence of moveable gas within the reservoirs.
Confirmation to come
While the results to date are described as encouraging, the joint venture will now move to confirm reservoir performance and fluid properties. Schlumberger’s Ora intelligent wireline formation testing platform will be run across up to two zones in the Waarre A reservoir to conduct controlled drawdowns and buildups, assess mobility and connectivity, perform downhole fluid analysis to confirm hydrocarbon phase and composition, and recover representative samples for PVT and compositional laboratory testing.
The Essington-1 discovery is the first in the Otway Basin since 2021 and marks an early success in ConocoPhillips’ new exploration push in the region. The well is the first in a planned two-well program under the Otway Exploration Drilling Program, with a second exploration well scheduled to spud in December.
The market likes it
ConocoPhillips holds a 51% operating interest in VIC/P79, alongside Korea National Oil Corporation with 29% and 3D Energi with 20%. News of the discovery sent 3D Energi shares up as much as 56% in early trade as investors responded to the potential scale of the find and its implications for the company’s Otway portfolio.
Shares in TDO are currently sitting 43,48% higher (1pm) at $0.165.
The Otway campaign comes as producers race to shore up future supply for Australia’s tightening east coast gas market, with output from legacy Bass Strait fields in decline and forecasts pointing to increasing reliance on new sources of domestic gas later this decade.