Mt Ridley Project
The Company’s Mt Ridley Project is comprised of four tenements (100% owned) in the highly prospective Albany-Fraser Province approximately 60kms north-east of Esperance in the highly prospective Albany-Fraser Belt of Western Australia. The town of Esperance is well equipped with road, rail, gas and a deep-sea port ideally suited for any company exploring in this part of the Albany-Fraser aiming to go into production. (Figure 1). The company is actively targeting nickel-copper sulphide deposits in the province, the site of Independence Groups’ world class Nova Nickel-Copper Mine.
Figure 1: The Mount Ridley Mines Ltd Albany-Fraser Range exploration portfolio.
The Mt Ridley project area most likely represents a previously unidentified Fraser Zone crustal element with what appear to be identical geochemical, geological and geophysical characteristics to the tectonic terrane that hosts the Nova nickel-copper sulphide ore body some 180 kilometres to the northeast (Figure 2).
The Mt Ridley Nickel-Copper sulphide project has demonstrated potential for discovery of magmatic nickel-copper sulphide. The geology and geochemistry of the varitextured and nickel-copper sulphide mineralised mafic-ultramafic intrusive-hosted systems drilled to date on the project offer significant encouragement to continue exploration efforts. The tenor of sulphides intersected to date at 3.5-4% nickel in sulphide show the project hosts true magmatic nickel-copper sulphide systems. It remains for further exploration to find sufficient accumulation of such sulphides as to be economic.
Detailed geophysical magnetic and gravity survey results
acquired to date are high quality and show detailed information
that will be used for target selection to identify other potential
Figure 2: Regional gravity image showing the extension of the important gravity corridor into the company's tenure, Albany-Fraser Range Province.
Many such targets have been identified from the geophysical data and remain to be tested (Figure 3). Of the limited number tested so far, three have identified magmatic nickel-copper sulphides hosted in varitextured mafic-ultramafic intrusive bodies with geochemical signatures characteristic of the other intrusive suites identified elsewhere within the Fraser Zone that host magmatic nickel-copper sulphides, including Nova. These data sets offer a powerful first pass prioritisation tool for exploration for this type of deposit.
Figure 3: Reduced to pole magnetic image showing priority target locations interpreted from the magnetic data. Different colours represent different magnetic characteristics to be tested for potential intrusive complexes.
Each of the targets will be progressively field checked with an appropriate combination of air core and diamond drilling and deep penetration ground electromagnetic surveys. The company is utilising ground based high-powered moving and fixed loop electromagnetic surveys, as well as borehole electromagnetic surveys, over high priority targets as this represents the best proven technique to detect magmatic nickel-copper sulphide accumulations.
While maintaining primary focus on the core nickel-copper sulphide potential, the area is also considered prospective for Broken Hill-type Lead-Zinc deposits, and although of a lesser priority exploration should remain opportunistic to gold. The regional gneissic country rock sequences that host the mafic-ultramafic intrusive bodies share many similarities with terranes around the world that host Broken Hill style mineralisation. Base metal prospectivity is interpreted to be greatest at the transition from magnetically complicated areas to areas that are magnetically quiescent on the flanks of the central gravity high feature, as this may represent the transition from active rifting to sag-phase sedimentation analogous to the Broken Hill orebody setting in NSW. Exploration activity will test this prospectivity alongside the high-priority nickel-copper sulphide exploration program.