Highlights

  • Macallum New Energy updated prospective gas resource estimates for its 100%-owned EP 494 permit in the North Perth Basin.
  • The combined mean prospective sales gas estimate for Gadee East and Gadee West was reported at 221 PJ after interpretation of 2026 seismic data.
  • The Barberton Terrace Deep prospect was remapped at a shallower depth than previously interpreted, which the company says could reduce expected well costs.
  • All prospective resource figures remain unrisked and relate to undiscovered accumulations rather than reserves or contingent resources.
  • The company plans further well planning and a farmout process ahead of a targeted exploration drilling campaign in the second half of 2027.

Macallum New Energy Limited (ASX:MNE) is an oil and gas exploration company focused on the assessment and potential future development of its 100%-owned EP 494 and EP 511 permits in the onshore North Perth Basin of Western Australia. The latest EP 494 update reflects how seismic work completed in 2026 has changed the company's interpretation of several gas prospects, particularly Gadee East, Gadee West and Barberton Terrace Deep.

Gadee Prospects Reassessed After 3D Seismic

Macallum said its 117 square kilometre Barberton 3D seismic survey, acquired in early 2026, improved structural definition across the Gadee prospects. The company reported a combined mean prospective sales gas estimate of 221 PJ for Gadee East and Gadee West, compared with 130 PJ cited in its February 2026 prospectus.

Gadee East was assessed with a low-to-high gas range of 60 PJ to 340 PJ and a mean of 182 PJ. Gadee West was assessed at 11 PJ to 77 PJ, with a mean of 39 PJ, together with an oil range of 3 million to 30 million barrels. These figures are prospective resources and therefore depend on future exploration establishing whether Hydrocarbons are present in commercially meaningful quantities.

Barberton Terrace Deep Remapped

The company also revised the mapping of the Barberton Terrace Deep prospect, placing it about 250 metres shallower than previously interpreted. Macallum said the change may reduce the expected cost of a future well. The prospect targets Permian and Triassic sandstone intervals and carries a reported low-to-high gas range of 343 PJ to 3,134 PJ, with a mean estimate of 1,513 PJ.

Across the broader EP 494 prospect inventory, Macallum reported arithmetic totals of 570 PJ in the low case, 1,860 PJ in the best case and 5,172 PJ in the high case, with a mean of 2,506 PJ. The company noted that these totals are indicative because aggregation assumptions can affect the way low and high cases are interpreted.

Exploration Risk and Development Path

The resource estimates are unrisked and carry both discovery and development risk. Macallum reported geological chances of success of 29% for Barberton Terrace Deep, 40% for Gadee East, 29% for Gadee West, 17% for Yarra Lead and 25% for Aberfeldy, with reported development chances of 50% to 55%. Yarra remains a lead because 3D seismic coverage is incomplete, while interpretation work continues across other areas of the permit.

The company is targeting an exploration drilling campaign in the second half of 2027. It also intends to begin a farmout process to seek a strategic joint venture partner for up to two wells. Preliminary well planning covers Aberfeldy, Gadee East, Gadee West and Barberton Terrace Deep, with locations expected to be selected in early 2027.

Key Insights

The 2026 seismic programme has given Macallum a more detailed structural view of EP 494 and has led to revised prospective resource estimates across several targets. However, the figures remain estimates for undiscovered accumulations and do not represent reserves or contingent resources. The next phase will depend on further technical work, well selection, farmout progress and future drilling results.