Macallum New Energy Lifts Gadee Gas Estimate 70% and Seeks Partner for 2027 Drilling
Key Takeaways
- Combined Gadee East and West Mean Prospective Gas Resource has risen 70% to 221 PJ from 130 PJ in the February 2026 IPO Prospectus, driven by the 117 km² Barberton 3D seismic survey.
- Barberton Terrace Deep carries 1,513 PJ of gas at a 29% Pg, and revised mapping places it 250m shallower, lowering the expected well cost.
- Gadee East shows an anomalous seismic amplitude, but with no nearby well it may not be possible to separate gas from wet sands without drilling.
- MNE will start a farmout to find a joint venture partner for up to two wells in H2 2027, with a well location decision expected in early 2027.
- A 12-month permit extension pushes the EP 494 well commitment to November 2028, giving MNE buffer beyond its H2 2027 target.
Gadee gas resource lifts 70% after Barberton 3D seismic
Macallum New Energy (ASX:MNE) has updated the Prospective Resource estimates for its 100%-owned EP 494 exploration permit in the onshore North Perth Basin. The headline is a 70% increase in the combined Gadee East and Gadee West Mean Prospective Gas Resource, now 221 PJ versus 130 PJ in the MNE IPO Prospectus of 23 February 2026.
The update follows interpretation of the 117 km² Barberton 3D seismic survey, acquired in early 2026, plus advanced reprocessing of the Mogumber North 2D survey acquired in 2022. MNE also intends to start a farmout process to find a strategic joint venture partner for drilling of up to two wells in H2 2027.
Andy Furniss, Chief Executive Officer
“…The Company’s focus and deep technical knowledge of the Perth Basin has delivered a mature portfolio of opportunities in an unprecedented timeframe with a combined Mean Prospective Gas Resource in excess of 2,500 PJ…”
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Updated EP 494 Prospective Resource estimates
A Prospective Resource is an estimate of petroleum in an accumulation that has not yet been drilled. The table below shows the Jurassic-age targets, all stated as gross unrisked mean volumes and 100% net to MNE.
Jurassic targets de-risked
| Prospect or lead | Status | Gas Mean (PJ) | Liquids Mean | Pg / Pd |
|---|---|---|---|---|
| Gadee East | Prospect | 182 PJ | Condensate 1.36 MMbbl | 40% / 55% |
| Gadee West | Prospect | 39 PJ | Oil 15 MMbbl (condensate 0.29 MMbbl) | 29% / 55% |
| Yarra | Lead | 199 PJ | Oil 25.1 MMbbl (condensate 1.50 MMbbl) | 17% / 55% |
Pg is the chance of geological discovery, and Pd is the chance of development once a discovery is made. Low Pg figures are normal for undrilled targets, which is why drilling matters so much.
The 3D data now defines Gadee as two separate fault blocks containing multiple stacked reservoir sands. The seismic amplitude response at Gadee East is anomalous relative to background levels, and the anomaly appears to conform to the area of maximum closure.
There is a catch. With no nearby well for calibration, it may not be possible to discriminate gas sands from high-quality wet sands without drilling a well.
Yarra remains a lead because a data gap persists over the interpreted structural crest. Additional 2D seismic data may be required before drilling to position the well optimally.
Barberton Terrace Deep: Permian and Triassic scale
Barberton Terrace Deep (BTD) carries a gross unrisked Mean of 1,513 PJ gas plus 6.81 MMbbl condensate, with Pg of 29% and Pd of 50%. The company describes BTD as “possibly the largest undrilled Permian and gas prospect in the Perth Basin”.
- The best estimate (2U) for the Permian reservoirs has reduced, but this has been largely offset by a new Triassic-age target in the Lower Lesueur Sandstones.
- The 1U-3U range has narrowed due to improved confidence from the enhanced seismic data.
- Revised mapping positions the prospect 250m shallower than previously imaged, which reduces the exploration well cost.
A narrower range means the estimate is less spread out, which suggests the reprocessed data has given the technical team firmer footing.
Understanding Prospective Resources and risk
Prospective Resources are quantities of petroleum estimated, as of a given date, to be potentially recoverable from undiscovered accumulations. Nothing has been proven until a well tests the target.
The volumes here are “unrisked”, meaning they do not incorporate the chance of geological discovery (Pg) or the chance of development (Pd). Think of them as the size of the prize if everything works, not a forecast.
The 1U, 2U and 3U labels are the low, best and high estimates under SPE-PRMS (2018). They correspond to P90, P50 and P10, meaning a 90%, 50% and 10% probability respectively that the stated volume will be equalled or exceeded.
The Mean is the arithmetic mean of the full probability distribution and is not, in general, equal to the 2U Best Estimate. That is why Gadee East shows a Mean of 182 PJ against a best estimate of 150 PJ.
Molyneux Advisors Pty Ltd, a Perth-based independent petroleum advisory firm, prepared the estimates using a probabilistic method. The totals are different: the arithmetic Total 1U and 3U figures are simple sums, and the announcement says they should be treated as indicative rather than as rigorously derived probabilistic aggregates.
For investors, drilling is what converts estimates into discoveries. Further exploration, appraisal and evaluation are required to determine the existence of a significant quantity of potentially moveable hydrocarbons.
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Path to drilling in H2 2027
The announcement sets out the following next steps:
- A farmout process to identify a strategic joint venture partner/s.
- Well planning studies for Aberfeldy, Gadee East, Gadee West and BTD.
- A decision on a specific well location, expected in early 2027.
- Continued processing of the Condor 2D seismic survey, acquired in May 2026, with updates to be provided in a future announcement.
MNE has also received a 12-month extension to the EP 494 permit work program from DMPE. This extends the well commitment until November 2028, although the company states it remains committed to a timeline targeting H2 2027.
For you as an investor, the picture is a portfolio the company describes as de-risked and drill-ready, aimed at the predicted WA domestic gas shortages from 2030. A joint venture partner could potentially share drilling costs, which matters for a company still at the exploration stage.
The strategic position is clear: MNE holds 100% of EP 494, a multi-prospect portfolio, and a defined timetable to bring a partner in and drill.
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