Great Northern Minerals Finds Deeper Douglas Creek Gold-Copper Targets

Deep Geophysical Targets Reframe Douglas Creek

Great Northern Minerals Ltd (ASX:GNM) has found what it says are compelling new drill targets at Douglas Creek, after induced polarisation and magnetic inversion work outlined at least three undrilled chargeability anomalies. The signals are supported by surface geochemistry, including gold, copper, silver and bismuth, giving the company a more substantial exploration model than the shallow drilling completed to date.

The most important limitation is also the clearest opportunity: previous drilling averaged about 50 metres in depth and did not test the newly defined anomalies. GNM says the targets may reflect intrusive-related or skarn mineralisation at depth, although that remains a geological hypothesis rather than a discovery or resource estimate.

Magnetic Tonalite Body Extends to Depth

Three-dimensional inversion of the magnetic data indicates a strongly reverse-polarised, porphyritic tonalite body measuring about 1.5 kilometres by 500 metres and extending to an interpreted depth of roughly 1 kilometre. A separate eastern apophysis appears to sit beneath the central chargeability anomaly, where shallow drilling returned up to 18.7 g/t silver, 0.22% copper and 77.5 parts per million bismuth over a reported interval of up to 2 metres.

Rock sampling above that eastern feature returned up to 1.0 g/t gold, 0.5% copper and 1.0% bismuth, but the area has never been drilled. To the north, further chargeability anomalies along the western margin of the magnetic body are also undrilled and unsampled by soil programs; rock samples along that trend returned between 0.1 g/t and 13.6 g/t gold, alongside copper, silver and bismuth values.

North Queensland Analogies Add Geological Interest

GNM links Douglas Creek's geophysical characteristics and Permian-Carboniferous intrusive rocks to intrusion-related gold-copper-bismuth systems in North Queensland, including Mt Leyshon and Kidston. The company says Mt Leyshon also features a reverse-polarised magnetic signature and a strong IP chargeability response, with the magnetic anomaly associated with magnetite-rich alteration near the deposit.

That comparison helps explain why the new anomalies matter, but it does not establish that Douglas Creek hosts a comparable economic system. No new drilling or geochemistry was reported in this announcement, and the company acknowledged that the mineralisation style at the project remains poorly understood.

Sampling Comes Before Mid-2027 Drilling

GNM has mobilised a follow-up soil program over the southern IP anomaly and is conducting stream sediment sampling around similar reverse-polarised magnetic features to the north. It plans to use those results to rank drill targets, then begin permitting once the detailed program is confirmed.

Drill testing is expected in mid-2027, after the upcoming wet season. That timeline leaves several gates still to clear: geochemical validation, target selection, permitting and the eventual test of whether the geophysical responses contain mineralisation at depth rather than simply marking favourable host rocks.