Helix Resources Ltd (ASX:HLX) is preparing for new drill testing after undertaking ongoing, aggressive target generation and drill testing work aimed to make new copper discoveries in the Cobar-Nyngan area of central NSW.
A programme to test a series of prospective copper targets at the Fiveways and Quanda-Hermidale target areas, located on the Collerina Trend, utilising a mixture of diamond core and reverse circulation (RC) drilling has recently been completed.
Whilst downhole geophysical surveys are due to be completed shortly, to date, no significant copper mineralisation was observed in the geological logging. All assays are pending.
The drill rig is now mobilising to the Black Range target located at the northern end of the Rochford Trend.
Fiveways
At Fiveways, a 253.2 metre (m) deep diamond core hole (FWDD004) tested a new target, CSV1, identified in turn by airborne and then ground based electromagnetic (EM) surveys.
The hole intersected a sequence of deformed psammite, pelite and mafic schist lithologies with zones of intense shearing, and significant chlorite alteration. Trace to weak iron and copper sulphide mineralisation is associated with the shearing. A strongly sheared graphitic black shale was intersected at the predicted target depth.
The black shale unit is the likely source of the conductivity anomaly; however, the shearing and associated alteration is certainly significant and relevant in assessing the regional copper potential. Drill core processing and logging of FWDD004 is in progress.
Quanda-Hermidale
The Quanda-Hermidale targets comprise three basement conductors detected by airborne and ground-based EM surveys, supported by regional anomalous magnetic data. Two RC holes were planned for each conductor, however one hole was abandoned at 132m due to swelling clay and recollared approximately 200m to the southeast. A total of seven holes were therefore completed for a total 1,230m.
The RC holes intersected transported clays down to depths of 27m to 42m followed by weathered psammite to 55m to 75m and a variably chlorite-altered mafic unit with magnetite-rich zones to the end of hole.
No significant sulphide mineralisation was intersected, however minor pyrite is present in some holes. There was no obvious source for the modelled basement conductors. The association of chlorite alteration and magnetite are common features of mafic units proximal to copper mineralisation elsewhere in the district and further studies are planned to assess the significance of this association.
Logging of the RC holes has been completed and samples have been submitted to the laboratory for analysis with results expected in four to six weeks.
Three holes were cased with PVC in preparation for downhole EM (DHEM) surveys on the CSV1, CNV1 and CNV3 conductors. The DHEM surveys are expected to be completed in September.
The drill rig will now move west to the Rochford trend for initial drilling in the Black Range area at the historical copper workings and a new gold target. The Black Range copper target holes will be surveyed with downhole EM to guide future drill targeting. Follow-up drill holes will be planned after results are received. Drilling is also planned for the recently upgraded Bijoux3 prospect, pending receipt of recent infill auger results and regulatory approval.
Fiveways and Quanda are the first of a series of targets we are testing with drilling,” Managing Director, Mike Rosenstreich, said.
“At Fiveways, whilst we still have to undertake the detailed geological work, downhole EM and assaying, I suspect the black shale intersected in the drill hole explains the conductive anomaly. The alteration and deformation intersected are certainly noteworthy and with the regional geochemical sampling work may further illuminate copper potential in this broader area.
“The Quanda-Hermidale targets were valid, greenfield targets – we drilled them and at this stage cannot explain the conductive anomalies. We will assess the results in total with lithogeochemical data before any final decisions on any follow-up work.
“Importantly, we now move onto the next target area – Black Range, on the Rochford Trend to undertake the first stage of target evaluation drilling ahead of a short break in the drilling.
There is much promising copper target generation work in progress creating a pipeline of targets for Helix to test. That is what we are focused on doing and I look forward to providing further updates.”
