Oonagalabi 2025 Geophysics and Drilling Collaborations Program Final Report (VTEM) EL 32279

Abstract

An airborne electromagnetic survey (VTEM Max) was completed over the full extent of EL32279 specifically to identify semi-massive to massive sulphide conductors that might be associated with the advanced greenfields Oonagalabi Cu-Zn-Au-Ag prospect. Oonagalabi is interpreted to have formed within a syngenetic, SEDEX-type or an epigenetic carbonate-replacement / skarn-type environment and these deposits are known globally to host high-grade conductive mineralization. Stratigraphic conductors or overburden are not present within the project and VTEM was considered the most appropriate technique to define sub-surface, sulphiderich mineralization. Other than some trial VLF lines in the 1970's, no electromagnetic technique had been completed at the Oonagalabi Project. The prospect currently has a reasonably well-defined, low-grade, disseminated sulphide zone that is estimated to host a non JORC-compliant resource of approximately 25Mt @ 0.5% Cu, 1% Zn, 0.1 g/t Au, 4 g/t Ag. In February 2025, Litchfield Minerals completed a Pole-Dipole IP survey (PDIP) that defined a +1km long, +20mV/V chargeability anomaly (to +60mV/V) that is up to 300m wide with a vertical extent exceeding 200m from surface. Historic and 2025 RC drilling clearly demonstrated that the IP chargeability anomalies are related to disseminated sulphides. This sulphide zone is hosted within the Oonagalabi Formation (dominantly anthophyllite, calc-silicate, marble and garnet quartzite) and is interpreted to host higher-grade feeder zones or remobilized sulphide mineralized zones. The PDIP survey defined extensive zones of chargeability with no geological surface expression, highlighting the importance of geophysics to improve sub-surface 'visibility'. The VTEM survey produced a high quality dataset that defined six high-priority, late-time sulphide-bearing basement conductors including four conductors within the older Aileron Province basement and two conductors within the over-thrusted and younger Irindina Province. Conductors were modelled by Kate Hine (Mitre Geophysics) and subsequent RC drilling of the VT2 conductor in late 2025 (OGRC011, OGRC019) intersected narrow zones of stringer, semi-massive and massive sulphides (pyrrhotite-chalcopyrite-sphalerite) hosted within metamorphosed mafic intrusive rocks (amphibolite). RC drilling of the VT1 conductor (OGRC012) intersected a 60m zone of weekly disseminated sulphides (pyrite-chalcopyrite-pyrrhotite) within felsic gneiss, amphibolite and an 8m wide massive quartz vein. Subsequent downhole EM and ground EM at VT1 defined two small conductors (50m strike, 1,500S and 3,000S), approximately 50m to the south and updip from OGRC012. Outside of VT1 and VT2, additional conductors within the Aileron basement are all spatially-associated with depth persistent magnetic anomalies, most likely relating to amphibolite intrusions. The two priority conductors within the overlying Irindina rocks are less well-developed than in the Aileron basement and are most likely related to Virginia-type, structurally-controlled epigenetic copper mineralisation.