King River Resources has substantially widened the exploration lens at its historically high-grade Mindoolah gold project in Western Australia, kicking off a multi-pronged geophysics and geochemistry campaign designed to light up new drill targets well beyond the old mine workings.
The company has commissioned a high-resolution airborne magnetic survey across 260 square kilometres at the project, 70km north-west of Cue in the Murchison gold province. The expanded program follows a smaller high-resolution survey that recently defined four priority targets from previously unrecognised structures and interpreted alteration zones.
The 5939 line-kilometre survey will be flown at a tight 50m line spacing to map Mindoolah’s broader structural architecture – effectively the geological plumbing King River believes may control the gold mineralisation. North-south traverse lines will be crossed by perpendicular east-west tie lines spaced 500m apart across the broader project.
The company will zero in on shear extensions, cross-cutting structures, geological contacts, fold-shear interactions, alteration zones and possible repetitions of known mineralised trends.
In parallel, 418 soil samples will be collected next week across undisturbed priority ground around the Mindoolah Mining Centre. Samples will be taken at nominal 50m intervals along lines spaced 180m and 280m apart, targeting areas identified through recent magnetic interpretation, historical mining and drilling, geological mapping and interpreted structural corridors.
Ultrafine+ soil analysis will sniff out any subtle geochemical fingerprints associated with prospective structures and geological contacts, particularly across areas where previous systematic exploration has barely scratched the surface. The company says the new magnetic and geochemical datasets will then be combined with existing geological models and pending assays from King River’s recently completed phase one drilling to refine and rank its highest-conviction targets ahead of its phase two reverse circulation drilling campaign in October.
The overall strategy is designed to test King River’s theory that Mindoolah may represent a considerably bigger structurally controlled gold system than its historic workings suggest. Those workings have plenty of pedigree, with more than 5700 ounces historically produced at a reported average grade of 19 grams per tonne (g/t) gold.
King River Resources managing director Graham Gadsby said: “These programs will substantially expand our geochemical and geophysical coverage across the project, allowing us to map prospective shear corridors and potential alteration zones well beyond the historic mining footprint.”
With the wider hunt taking shape, King River has already lined up the drill rig. The company has secured Jarahfire Drilling as its preferred reverse circulation contractor, with mobilisation expected in early October. Phase one assays are expected before phase two drilling begins.
The airborne survey is scheduled to start early next month and take 10 days, followed by roughly eight weeks of third-party data processing and structural interpretation. That interpretation will slot in alongside the incoming soil results as King River pieces together its final targeting picture.
Earlier LiDAR and volumetric modelling added another piece to the puzzle, estimating more than 1.08 million tonnes had been excavated from historic pits as opposed to just 746,000t of dumps and stockpiles still at surface, suggesting some unaccounted-for material.
Historical mining was constrained by groundwater at depths of only 20m in places – one reason King River believes plenty of the system may remain to be tested. The opportunity extends beyond the old workings, with parts of the prospective greenstone package masked by shallow cover and stronger regional magnetic signatures that King River says may have obscured the subtle structures it is chasing.
The company interprets faults, shears and their intersections as potential pathways and traps for gold-bearing fluids. It also believes some historical drilling may have tracked sub-parallel to narrow lodes, potentially sailing straight past mineralisation and leaving tantalising gaps in Mindoolah’s gold story still up for grabs.
Mindoolah forms part of King River’s broader exploration portfolio alongside its other Western Australian projects, with the latest campaign putting the historic Murchison goldfield firmly in the company’s near-term exploration spotlight.
King River is now putting modern geophysics, geochemistry and structural interpretation to work across a much bigger slice of an old high-grade goldfield. With a vastly expanded magnetic picture taking shape and the drill crew booked for October, the company is stacking up its best targets before letting the drill bit deliver the verdict.
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By Penny Taylor
