Westar Resources Ltd (ASX:WSR) has kicked off its airborne electromagnetic survey (AEM) over the Opaline Well property in Western Australia’s Pilbara Mineral Field.
It’s the first time an AEM survey has taken place over the project area, where Westar is targeting both volcanic massive sulphide (VMS) and shear zone-hosted mineralisation.
The AEM program, using NRG’s ExciteTM airborne electromagnetic system will cover the entire project tenure — an area of approximately 70 square kilometres and 372 line kilometres — on 200-metre line spacing.
This survey is intended to rapidly identify discrete conductors that represent potential massive sulphide drill targets.
It will be completed by mid-late October, with final processed data to be delivered in four to six weeks after the survey is completed.
Ultimately, the AEM program marks the next step in Westar’s broader exploration campaign, which involves pinpointing priority drill targets for future programs.
Westar managing director Karl Jupp said: ” Our fieldwork and structural interpretations to date have highlighted the exciting prospectivity at Opaline Well and we are confident that the AEM geophysics proves to be a rapid and effective exploration tool that provides the key to fast-tracking VMS style target generation at the project.”
Recent fieldwork
Last month, Westar completed an initial field program and targeting exercise over the Opaline Well property.
That program returned rock chip samples results of up to 1.3 g/t gold and silver, barium, copper and zinc anomalism at the Triberton Creek prospect.
Additional rock-chip samples from the Opaline Well prospect assayed at 343 parts per million (ppm) lead, 1,080 ppm zinc and 508 ppm copper.
These confirm historical rock chips samples collected by Great Southern Mines in 1995 that returned assays of 0.35 ppm gold, 155ppm silver, 1.15% copper and 1.85% zinc in the Opaline Well prospect area.
Once complete, the AEM data will be used, together with the mapping and surface geochemistry results and interpretations, to generate plate models of electromagnetic anomalies for drill targeting.
Exploring a historical region
Situated in the Pilbara Mineral Field, the Opaline Well Project straddles the Coongan greenstone belt and western margins of the Kelly greenstone belt.
Interestingly, most of the Coongan and Kelly greenstone belts form part of the Pilbara Supergroup and consist of volcanic and sedimentary sequences.
The project area also contains several recorded historical workings, including Triberton Creek A and B, where historic rock chip samples revealed grades up to 200 g/t gold.
There’s also Opaline Well 1 and 2, where rock chip samples have returned grades between 0.25% and 1.15% copper, 0.14% to 1.85% zinc, 79 and 155 g/t silver and 0.19 to 0.41 g/t gold.
Other nearby historical mining centres include the Eidelweiss and Corboys regions.
Here, the Victory Mine enjoyed a limited production run of 1,929 gold ounces, and at Coongan Star, Consolidated Gold Mines generated 5,478 ounces of gold.