Charlemont-1 Gas Discovery Raises Questions on Commercial Viability and Next Steps
3D Energi has confirmed a new gas discovery at the Charlemont-1 well in Victoria’s Otway Basin, reinforcing the prospectivity of the Charlemont Trend and the potential for increased domestic gas supply.
- Gas discovered in Waarre C sandstone with 16 Mol% CO2 concentration
- Probable hydrocarbons detected in Waarre A sandstone pending further analysis
- Charlemont-1 discovery supports continuity of gas charge along Charlemont Trend
- Second gas find in Otway Exploration Drilling Program, following Essington discovery
- Well to be plugged and abandoned; further evaluation required before development
A Significant Step in Otway Basin Exploration
3D Energi Limited (ASX, TDO) has announced a promising gas discovery at the Charlemont-1 exploration well, located offshore in Victoria’s Otway Basin. The find, within the Waarre C sandstone, was confirmed through the recovery of a gas sample containing a preliminary 16 Mol% concentration of CO2, comparable to nearby La Bella gas field levels. This discovery was unexpected and highlights the potential for further resources within this geological unit across the Charlemont Trend.
Encouraging Signs in Multiple Reservoirs
Beyond the Waarre C sandstone, preliminary petrophysical data indicate probable hydrocarbon presence in the primary target, the Waarre A sandstone. Elevated gas readings and resistivity logs suggest hydrocarbons may be present, though confirmation awaits more detailed analysis. The lack of a continuous gas column across the Waarre units points to a complex reservoir system that will require further study to fully understand.
Validating the Charlemont Trend’s Prospectivity
The Charlemont-1 well sits at the down-dip end of a prospect chain extending to the La Bella gas discovery about 7 kilometres east. The presence of gas at both ends of this trend, combined with consistent seismic amplitude anomalies in the intervening prospects, strengthens the case for a gas-charged system along the entire Charlemont Trend. This continuity is a positive signal for future exploration and potential resource development in the region.
Strategic Implications for the East Coast Gas Market
Charlemont-1 marks the second gas discovery within the Otway Exploration Drilling Program (OEDP), following the recent Essington find. The program’s infrastructure-led approach appears effective in identifying new gas resources close to existing production and processing facilities. Executive Chairman Noel Newell emphasised the strategic importance of these discoveries for supplying Australia’s tightening domestic gas market, though he cautioned that further technical and commercial evaluations are necessary before development decisions can be made.
Next Steps and Outlook
With wireline logging complete, Charlemont-1 will be plugged and abandoned in line with environmental approvals. The Transocean Equinox rig will move on to other operations, while 3D Energi considers the potential for Phase 2 drilling under the existing Environment Plan. No decisions on further wells or development have been made yet, underscoring the need for continued analysis to assess commercial viability and optimal development pathways.
Bottom Line?
Charlemont-1’s discovery strengthens Otway Basin’s gas prospects but leaves key commercial questions open.
Questions in the middle?
- What will detailed petrophysical analysis reveal about hydrocarbon volumes in Waarre A and C sandstones?
- How might the 16 Mol% CO2 concentration impact the economics and processing of the gas?
- Will 3D Energi proceed with Phase 2 drilling, and what timeline might that follow?
