A recent drone aeromagnetics survey by Buxton Resources (ASX: BUX) has unveiled a north-east-trending cluster of magnetic anomalies in the south-central part of the company’s 100 per cent-owned Wolverine prospect in Arizona.
The cluster is about 250m wide and its 1.2km strike coincides with the orientation of copper-molybdenum mineralised porphyry dykes, with rock chip sampling yielding 1.2 per cent copper and 383 parts per million moly next to Buxton’s permitted drill site. Management says the magnetic anomalism could be related to mafic rocks in the area and/or concentrations of porphyry “B” veins.
Such vein assemblages are seen as unique indicators of a magmatic hydrothermal transition environment where porphyry type copper, gold and moly deposits form. The age of the site’s geology puts it in the same Laramide period – about 70 million years ago – as the rocks of the main Copper Wolf porphyry system.
The overall age, outcropping mineralisation, geology, geochemistry and geophysical characteristics of the previously untested area combine to make the recently-discovered Wolverine prospect a target which Buxton describes as “compelling.”
Given the close associations between magnetics and demonstrable mineralisation, management plans to extend its geological mapping and sampling initiatives. It will also undertake initial induced-polarisation (IP) geophysical surveying across selected areas in a bid to bring to light any additional targets for future drilling.
The State’s Bureau of Land Management has issued its approval for Buxton to drill from a single prepared site to keep ground disturbance to a minimum. But the approval can typically provide for several holes in the same location.
Buxton holds about 26 square kilometres of ground at its Copper Wolf project area, with the exception of a first right of refusal held by earn-in joint venture (JV) partner IGO. The earn-in and JV agreement for the main mineralised part of Copper Wolf was signed in August 2022, with IGO having an exclusive option to earn a 51 per cent interest in the tenements by undertaking sole-funded exploration expenditure to the value of $350,000 in a 24-month period that ends in October.
Copper Wolf is surrounded by some of the most prospective and historically productive copper porphyry terrain on the planet, but has been subject to remarkably little recent exploration drilling since the 1990s, with Buxton’s 2022 airborne magnetic survey being the first geophysical work undertaken since the early 1960s.
In 1993, a non-JORC “mineral inventory” resource estimate for an area, about 74 per cent of which lies within Buxton’s ground, was produced by Orcana Resources, yielding 388.3 million tonnes at 0.83 per cent copper and 0.07 per cent molybdenum disulfide. But it was not followed up until some 14 years later by Liontown Resources, with its JORC-inferred resource from just part of the supergene zone yielding 108 million tonnes going 0.8 per cent copper and 0.03 per cent moly (0.94 per cent copper equivalent) for 864,000 tonnes of contained copper metal and 32,400 tonnes of molybdenum metal.
The old adage of “you won’t find it if you don’t look” seems to apply to the region and there is plenty of evidence that persistent searching in the Copper Wolf project area – considered “hot property” by almost any measure –will almost certainly continue to turn up targets for Buxton.
Wolverine might be the first in this locality, but by the look of similar trends and signatures at the company’s nearby Hawkeye prospect, it seems unlikely it will be the last.
Is your ASX-listed company doing something interesting? Contact: office@bullsnbears.com.au