Lodestar Minerals Limited (ASX:LSR) has confirmed and refined model conductors for priority drilling with the results of the fixed loop electromagnetic surveys (FLEM) completed over the SC-3, MC-8 and MC-9 conductors identified by the regional Xcite heli-EM survey in the Earaheedy Basin in WA.
Lodestar holds a strategic land position on the northern margin of the Earaheedy Basin, 70km north east from Rumble Resources’ major Zn-Pb discoveries. The Proterozoic sedimentary-mafic sequence within the project is stratigraphically below the Frere Iron Formation and is believed to have potential to host SEDEX, VMS-style and epigenetic, structurally controlled base metal mineralisation.
Fixed loop EM surveys over the SC-3, MC-8 and MC-9 conductors within the “Imbin corridor” have been modelled as potential massive sulphide Cu-Pb-Zn targets within the sedimentary sequence. Surface mapping indicates consistent tight to open asymmetric folding about NNW trending fold axes and later folding about east-west trending fold axes. Folds are disrupted by anastomosing NNW trending shears interpreted as NE dipping thrust faults. The models resolved by the FLEM surveys appear to be consistent with these macro structural trends.
The SC-3 conductor is located 3.5km southeast of “Main Gossan” copper prospect in an area where historic Zn and Pb anomalies were identified in rock samples2. The FLEM survey has resolved a moderate strength conductor (600m x 300m, ~1200-1500S) target dipping 15- 25deg to the N-NNE.
The MC-8 conductor is located along strike and 700m north west from the “Main Gossan” copper prospect in an area of deflection in the regional geology. The MC-8 FLEM plate model is interpreted to reflect a folded sequence with north and south dipping limbs/plates; the target plates dip 30-55deg to the SSW (900m x 300m, moderate to high conductance ~1400- 4000S) and 40-50deg to the N (600m x 150m, moderate conductance ~2000-2500S), respectively.
The MC-9 conductor is located on the southern fold limb of the ‘North Chert” prospect. North Chert is an historic prospect where surface copper and gold anomalies have been targeted by wide spaced shallow drilling, generally within the zone of oxidation. The MC-9 target also resolved into an interpreted fold with limbs/plates dipping 10-20deg to the NE (600m x 400m, moderate conductance ~1250-1750S) and 40-60deg to the SW (1000m x >600m, moderate conductance 1000-2000S).
Next Steps
- A drilling programme of ~1,000m in total is designed to intersect each of the target conductors below the base of oxidation. Requests for heritage clearance surveys and statutory approvals will be submitted and site preparation and drilling will commence once approvals are in place.
- The three FLEM conductor targets (SC-3, MC-8 & MC-9) were selected from 30 regional discrete conductors identified within the 20km by 8km area of the Xcite heli-EM survey because of proximity to known mineralisation at Main Gossan and historic geochemistry. Results from the regional UFF ultrafine fraction soil sampling are expected in coming weeks and will guide selection of targets to be tested in the main phase of exploration drilling within the Imbin corridor.
