Terrain launches geophysics blitz on WA Yalgoo gold play

Terrain Minerals has launched one of its biggest induced polarisation (IP) geophysical surveys yet at the company’s Smokebush gold and silver project, 350 kilometres north of Perth in WA, aimed at sniffing out repeats of its Lightning-style gold target.

The survey will cover the granted mining lease in the extreme north of the Smokebush project, which contains the Lightning and Monza gold deposits and untested surrounding ground. It has been designed to pinpoint parallel or linked gold-bearing structures within the same north–south shear corridor and near-granite structural setting that hosts both deposits.

Terrain has prior form with IP at Smokebush. A 2023 IP program over Lightning, which lies 50 metres west of and parallel to the Monza structure, outlined a 600m chargeability anomaly that was later drilled, delivering multiple high-grade hits, including 13m at 8.13g/t gold from 122m. 

More recently, an IP survey at Wildflower defined three targets extending more than 800m, with reverse circulation drilling completed earlier this year and assays due shortly. 

This latest IP survey is designed to keep the company’s exploration pipeline stocked as it closes in on a maiden “starter” mineral resource estimate at Lightning in July. 

Management believes its application of modern geophysics could help sharpen targeting and unlock a proper follow-up program. 

Adding to its credentials, the new survey area sits within the Mt Mulgine intrusive corridor between Lightning to the east and the historic Black Dog open-cut mine, 4km west of Terrain’s northern mining lease boundary.

The western portion of the company’s granted mining lease has not been tested with modern IP and is the largest remaining untested area within the lease. Whilst out in the field, the company will also roll out infill IP survey lines across the nearby historic Hurley prospect, 2km southeast of Lightning/Monza. 

Shallow drilling at Hurley by previous explorers returned anomalous gold, including 10 metres assaying 1.4 grams per tonne (g/t) gold from 15m depth within a 250-metre by 250-metre soil anomaly. 

Terrain Minerals executive director Justin Virgin said: “What excites us the most is that this target area has never previously been tested with modern IP, despite sitting within the same structural corridor as Lightning. The geology, structure and regional setting all suggest there is strong potential for additional parallel gold-bearing structures across the broader Smokebush system.”

Induced polarisation is a handy, rapidly deployable and non-intrusive geophysical tool that can highlight chargeable sulphide minerals often found in and around gold systems. The method can assist explorers in aligning drill targets beneath shallow cover without blindly punching holes into the ground. 

The field data acquisition is expected to take between 11 and 20 days, followed by processing and modelling through June, before drill-ready targets are reported in July alongside the company’s upcoming Lightning resource numbers.

Follow-up drilling across the broader Smokebush system is pencilled in for the second half of 2026. 

With Wildflower assays on the horizon and a fresh batch of Lightning-style targets likely to come into view, Terrain is shaping up for a busy run of news flow as it sets out to show Lightning could be the first show in a much bigger performance.

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au