PATERSON RANGE PROJECT, WESTERN AUSTRALIA

Avira holds two tenements in the Paterson Province of Western Australia, a highly prospective Neoproterozoic metasedimentary basin which is host to several world-class mines such as Nifty and Telfer. Recent exploration success at Winu by Rio Tinto and at Haverion by Greatland Gold has reinvigorated interest in the province.

 Avira’s strategic review identified the Paterson Province as being one of the least explored and most prospective geological terranes for discovery of significant copper and gold ore bodies.

Avira Resources sought entry into the Paterson province after the discovery of Haverion by Greatland Gold. As a consequence of this focus on the region, Avira identified open tenure and pegged Throssel Range E45/5567 as well as completing the purchase of Mount Macpherson E45/5572 in late 2019 (Refer previous ASX announcements). Avira notes that joint venture activity in the Paterson Province has seen expenditure commitments made by mining majors (through JVs on junior mining company tenements) exceed $50M in the past 12 months. 

Encounter Resources (ASX:ENR) announced it had entered into an earn-in  and Joint Venture arrangement with IGO Limited covering Encounter’s Yeneena copper-cobalt project in the Paterson Province. The agreement commits IGO to fund up to A$15m in exploration expenditure to earn a 70% interest in Yeneena.Both of Avia’s projects border the ENR/IGO Yeneena project. Additionally the south western boundary of Mount Macpherson is in close proximity to the magnetic anomaly associated with Encounter’s Aria Prospect. The Vines fault appears to extend into the Throssel Range prospect’s southern border with the Yeneena Project.

Avira conducted and completed geological mapping, ground based geo-chemical soil sampling and an airborne geo-physical EM survey.

The company received the data and results from the high-resolution helicopter borne Xcite^tm electromagnetic and magnetic survey. The survey defined 152 conductive anomalies and coincident magnetic responses in the subsurface geology of the project areas with several extensive anomalous responses encountered on multiple flight lines. Eighty six conductive anomalies occur on the Throssel tenement and sixty six on the Mount Macpherson tenement.

Several of these anomalies continue for several kilometres along strike within interpreted structures. These anomalies are defined by discrete late-time conductors, modelled at shallow depths which are potentially caused by sulphide mineralisation. Avira considers these are compelling structural and geophysical targets for further exploration.

Data was collected and processed by specialist geophysical consultancy Southern Geoscience Consultants Pty. Ltd. (SGC). Individual line profiles were visually inspected after processing and a series of anomaly picks generated. SGC has identified strong (red), moderate (Yellow) and weak (blue) conductors (figure 2) and defined a series of targets (figure 3). A tabulation of SGC’s targets is presented in the appendix, table 2.

 

Figure 2. strong (red), moderate (yellow) and weak (blue) EM Anomalies defined by SGC, on RTP magnetic imagery

 

Figure 3 Priority target zones highlighted by SGC from Paterson EM survey, on channel 25 conductivity image

 

Pipeline Target (SGC_5572_1 & 3)

Several subtle mid to late time EM anomalies are present on E45/5572, with a significant and extensive anomaly present along approximately 8 kilometres of strike through the tenement (figure 4) with 3 kilometres of conductor identified as ‘high priority’ by SGC (refer table 1).

The EM anomaly is coincident with a linear magnetic anomaly. The Pipeline Target has not been tested by Avira’s soil geochemistry and is concealed by wind-blown sand, alluvium, laterite and sand dunes. A broad early to late time conductive response is present to the immediate south-west of the Pipeline Target and is likely related to the laterite horizon.

Figure 4.  Channel 20 conductivity response over E45/5572 and Avira Resources interpreted targets

 

Gwardar Target (including SGC_5572_3)

A sinuous magnetic and conductive response is present within the broad laterite response with several conductive targets identified by the geophysical interpretation. Collectively these anomalies continue for approximately nine kilometres as elevated magnetism coincident with mid-time conductivity features. 

The anomaly is potentially related to sulphides within bedrock due to the coincidence of magnetic and conductive responses. The sinuous shape of the anomaly suggests that it is potentially folded and controlled by stratigraphic features in the basement. Geological mapping within this area has shown considerable deformation.

Extensive mid-time EM responses are present in the tenement with a NNW trend (SGC_5572_4), and are up to several hundred metres strike length. These anomalies coincide, broadly, with a set of tight, sheared out folds within the area. Other discrete late time responses in the south-east of the tenement (SGC_5572_2) occur in lateritised and covered terrain and require follow-up geophysics and in-fill geochemistry.

 

Throssel Range

The EM survey flown over the Throssel Range tenement has shown several discrete but subtle late-time responses that occur across one to three flight lines. These responses are associated with north-east structural corridors where the interpreted and mapped structures cut the conductive stratigraphy of the Tarcunyah Group (figure 3).

SGC’s target picks include SGC_5567_5, a strong conductor associated with possible demagnetisation and SGC_5567_3, a ~700m long mid-time response on 3 flight lines associated with a lithological contact within the prospective structural corridor.

Anomalies have been returned from the Archaean basement (SGC_5567_4) in an area mapped as greenstone (dolerite). Conductivity here is associated with a lithological contact and persists ~700m across 3 flight lines. The area has not been mapped or sampled and requires additional ground truthing.

The Avira EM survey has significantly improved the resolution of magnetic data over the project and has highlighted a significant NE trending structural feature (Pipeline Target) on E45/5772 which has coincident mid to late time conductors and magnetic anomalism (figure 4).

The Pipeline Target is interpreted to be caused by magnetic and conductive minerals within a NE trending fault structure. The conductive mineral is thought to most likely be pyrrhotite a magnetic sulphide that can explain coincident magnetic and EM anomalies. Pyrrhotite is known to be associated with base metal sulphide mineralization at other base metal prospects within the Paterson province and on this basis Avira considers that the Pipeline and Gwardar targets are prospective for base metal sulphide mineralization.

Within E45/5567 Throssel Range magnetic data has identified a north east structural trend which defines compartments of rock with varying conductivity. Avira Resources interprets this to potentially be caused by alteration of sulphides within the stratigraphy or deeper weathering. Subtle late time conductors exist on the contacts of the major stratigraphic units within the NE structural corridor,  and may represent sulphide mineralisation (Figure 3).

 

Follow Up Exploration

 The Company has now compiled the data from the initial exploration program including all available geological, geochemical and geophysical information. On interpretation of these results the Company is planning to undertake a ground based Moving Loop EM survey on priority areas of interest including; Pipeline, Gwardar and other Priority 1 Conductors.

The Company has received preliminary and incomplete soil sampling results and is planning on completing coverage over the tenements priority targets identified from the recent EM survey.

Planning is well underway with the Company’s geophysical consultant, with a crew scheduled to mobilise to site within four to six weeks to begin data collection with final results expected by the end of the Quarter.  

This focused ground-based program is designed to delineate priority RC drill targets within the areas of interest. The company intends to mobilise a drill rig and crew as soon as practicable pending receipt and interpretation of the geochemistry and geophysical data generated from this program.

The Company has begun preparing a Programme of Works, and (if required) a Heritage Clearance Survey to open up access tracks and base lines to support drilling activities. The timing of drilling will be contingent upon receipt of all land access and heritage clearances and satisfactory weather conditions.