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ActivEX’s Cloncurry Copper and Gold Project (total 1,091 km2) is located in northwest Queensland, near the town of Cloncurry. ActivEX Limited holds 100% interest in 13 tenements (EPMs 14955, 15285, 17313, 17805, 18511, 18073, 17454, 18852, 18053, 25192, 25194, 25454 and 25455).
ActivEX’s Cloncurry Copper and Gold Project is situated within the Eastern Succession of the Mount Isa Inlier, which is a highly prospective geological terrane containing numerous major deposits. These include Iron Oxide Copper Gold, skarn style Cu-Au, and Merlin-style Mo deposits (Table 1).
Table 1. Major deposits within the Eastern Succession, Mount Isa Inlier
The Project includes a number of established targets, with several drilling programs already completed by ActivEX.
Significant drilling intersections from the Florence Bore South #2 prospect include:
Significant drilling intersections from the Sterling prospect include:
Significant drilling intersections from the Saddle Ridge prospect include:
ActivEX has also completed ground based surveys at other prospects, including geochemistry, mapping, and geophysics.
Exploration targeting concepts include:
ActivEX’s Cloncurry Copper and Gold project is located south of Cloncurry in northwest Queensland (Figure 1).
The area is pastoral land utilised predominantly for cattle grazing and is accessed from the Barkly Highway, secondary bitumen and formed gravel roads (Duchess and Selwyn Roads) and by station tracks.
The tenements lie predominantly on the Duchess and to a lesser extent the Cloncurry 1:250,000 sheet areas, centred on longitude 140°46’ E and latitude 21°17’ S, see Figure 2. The areas cover the Marraba, Malbon, Cloncurry, Mount Angelay and Selwyn 1:100,000 sheet areas.
Figure 1. Cloncurry Copper and Gold Project Location
The Cloncurry Copper and Gold Project tenure comprises nine granted Exploration Permits and six Exploration Permit Applications in North-West Queensland with an area of 1103.95 km2 (Figure 2). The holdings have been divided into four discrete areas based on geography, geological setting and target styles.
Table 2. Summary of individual tenement details
Figure 2. Cloncurry Copper and Gold Project tenements
There are three Native Title Claims present in the project area. The northern Projects are covered by the title claims of the Kalkadoon and Mitakoodi Peoples and the Selwyn Project is partly covered by the claim of the Yulluna People. Right to Negotiate access agreements are in place with the Kalkadoon and Yulluna People.
Since the 1960s extensive mineral exploration has been carried out in the Cloncurry district. Despite the intensity of exploration, there have been remarkably few drilling campaigns carried out on the ActivEX projects. Drilling has been carried out from 1991 to 1997 principally by Arimco and MIM. Furthermore, the historical work programs have been carried out in a piece-meal fashion covering only a small proportion of the tenements. There is therefore significant potential for undiscovered ore bodies.
The following table is a brief summary of previous work (full summaries are provided in annual reports).
Table 3. Summary of historical exploration
The Cloncurry Copper and Gold project is located within the Proterozoic Mount Isa Inlier, which comprises variably metamorphosed metasediments, metavolcanics and intrusives. The Mount Isa Inlier is subdivided into the Eastern and Western Fold Belts, which unconformably overly the magmatic craton of the Kalkadoon-Leichhardt Block.
The Eastern Fold Belt stratigraphy has been subdivided from west to east into three tectonic zones: the highly deformed Mary Kathleen Zone, the less deformed Quamby-Malbon Zone, and the complex Cloncurry-Selwyn Zone (Figure 3). ActivEX’s projects lie predominantly in the Quamby-Malbon Zone with minor overlap into the Cloncurry Selwyn Zone.
The stratigraphy of the Mount Isa Inlier can be broadly defined by three “cover sequences” that are bounded by regional scale unconformities (Foster & Austin 2008). Cover sequence 1 outcrops solely in the Kalkadoon-Leichardt Belt and cover sequences 2 and 3 outcrop in both the Eastern and Western Fold Belts (Foster & Austin 2008). Cover sequence 1 is largely comprised of pyroclastic volcanics (Foster & Austin 2008). Cover sequence 2 is rich in calc-silicate rocks with lesser volcanic rocks (Foster & Austin 2008). Cover sequence 3 is dominated by siliciclastic rocks, including some black shales and volcanic units are also present (Foster & Austin 2008). ActivEX’s projects are hosted by Cover Sequence 2 units (Florence and Bulonga Projects) and Cover Sequence 3 units (Selwyn East and Cloncurry fault Projects). The Proterozoic rocks of the Mount Isa Inlier are bounded by the Georgina, Eromanga, and Carpentaria sedimentary basins, which onlap the Proterozoic rocks.
The Mount Isa Inlier has undergone a complex history of deformation and metamorphism, which has been widely debated and is poorly understood. The Isan Orogeny began at ca. 1600Ma and involved several deformation events, producing varying degrees of metamorphism. Three major ductile deformation events were described by Bell (1983, 1999), named D1, D2, and D3, based on work in the Western Fold Belt. D1 was interpreted to have produced E-W oriented folds and thrusts, D2 produced N-S folds and steeply dipping regional foliation, and the latest D3 resulted in folds and crenulations striking mainly NNW. Numerous workers have argued for and against this sequence, and proposed several variations, mostly involving additional deformation events.
Rubenach et al. (2008) have proposed a similar sequence for the Eastern Fold Belt, based on work mostly in the Cloncurry-Selwyn Zone. The earliest recognised foliation is sub-parallel with the bedding and was interpreted to be mainly extensional, with the event being named Dbp. D1 produced E-W folds with steep axial surfaces, best preserved in the area north of the Snake Creek Anticline. D2a produced N-S folds with mainly steep axial planes and the most intense foliation in the region (S2a). D2b resulted in small-scale folding with N-S axes, shallow axial plains, and top-to-the-west sense of shear. This event appears to have been very localised. The D3 event is recognised by almost all workers, and produced NNW-trending folds with steep axial surfaces, as well as crenulations and reactivation of S2a. The final recognised event, D4, resulted in NE-trending folds with steep axial surfaces, and further reactivation of S2a. Associated regional metamorphism varies from lower greenschist to upper amphibolite facies.
Various intrusive phases were emplaced during the Early to Middle Proterozoic, including the Williams and Naraku Batholiths, the Eastern Selwyn Range early granite suite, the Wonga Granite, and the Lunch Creek Gabbro. The earliest known tectonism to affect the Eastern Fold Belt was the Wonga extension event, occurring between 1750-1735 Ma (Holcombe et al., 1991; Pearson et al., 1992). This was accompanied by the intrusion of numerous granite plutons in the Mary Kathleen (Burstall, Wonga Suites) and Cloncurry-Selwyn Zones (Gin Creek Granite).
The Williams (Mt Angelay, Squirrel Hills, Mt Dore Yellow Waterhole Granite) and Naraku (Mt Margaret, Mavis, Malakoff granite) Batholiths intruded the Eastern Succession during the later stages of the Isan Orogeny, 1530-1500Ma (NWQMEPR 2011) and is believed to be related to significant copper mineralization in the Eastern Fold Belt (and is synchronous with the emplacement of the Mt Isa copper deposits). The Eastern Fold Belt has been affected by extensive metasomatism that is thought to be a product of widespread magmatic activity contributing fluids and heat with brittle faults acting as fluid conduits.
Figure 3. Regional geological setting
Figure 4. (LHS) - Aerial magnetics (TMI) over Florence Area, showing the outline of the Wimberu Granite Figure 5. (RHS) - Location of major prospects
ActivEX exploration activities over the Cloncurry Copper and Gold project have included:
Exploration has been concentrated at the Florence Bore North and Florence Bore South prospects and the immediate surrounds (Green Valley, Dandy Extended and Sterling prospects). The intersection of significant copper-cobalt gold mineralisation has focussed ActivEX’s attention in these areas.
ActivEX has identified several prospects consisting of outcropping haematite-copper oxide-granite breccias, which are typical of IOCG deposits such as Ernest Henry and Roxby Downs. These prospects are located within the Wimberu Granite (Figure 4).
ActivEX has completed a broad-spaced gravity survey over some of these prospects, with the aim of identifying areas of haematite breccia. Thirteen priority targets (i.e. IOCG and intrusive related) have been identified in the gravity data; the majority have yet to be followed-up (Figure 6) e.g. utilizing infill geophysical surveys, detailed geochemistry or drilling.
Figure 6. Published regional gravity data with ActivEX detailed gravity survey and gravity targets
The Saddle Ridge prospect is located in the south of the Project area and was initially drilled by MIM in the mid 1900’s. Best results from this program returned 40m @ 0.32% copper, 195g/t cobalt and 0.08g/t gold in hole MA002 from 24 metres. ActivEX has since completed detailed geochemistry, which defined an anomalous area of at least 5km in length and still open to the north. The structure is also interpreted to extend a further 8km northeast to the Young Australia copper mine.
ActivEX has completed an initial phase of drilling consisting of four RC holes, for a total of 550m. Best results included:
• 35m @ 0.85% Cu and 207 g/t Co, Including 6m @ 3.2% Cu, 206 g/t Co and 0.21 g/t Au.
• 40m @ 0.25% Cu, 96 g/t Co.
Further drilling is required to resolve the geology and extent of this prospect.
Previous drilling by Arimco had defined two Starra style targets in the Florence area based on magnetic anomalies and magnetite associated copper/gold mineralisation located in the contact aureole of the Wimberu Granite. Arimco drilled 5 holes at Florence Bore and 9 holes at Trump returning up to 4m @ 3% Cu, 0.3g/t Au from Florence Bore and 12m @ 2.9% Cu, 0.38g/t Au from Trump.
The Brightlands tenement (EPM 18511) contains a number of outcropping mineralized structures, with quartz vein and copper oxides. These have not yet been investigated by ActivEX.
The Selwyn East Project was initially the subject of several competitive EPM applications lodged in 2008. EPM 18073 was finally granted in September 2011 and additional ground was applied for in 2013. Highlights of this area include:
Walk up drill targets (no previous drilling)
Anomalous copper, uranium and rare earths associated with structurally related skarns, dolerites and granite contact
Anomalous molybdenum associated with black shale hosted structures and potential for Merlin-style mineralisation
The Selwyn East project area was targeted due to the occurrence of smaller fertile intrusives such as the Mt Dore and Yellow Waterhole Granites and the proximity to the mineralised structures through Starra, Mt Dore and Mt Elliott (see Figures 7 and 8). The application was made before the discovery of the Merlin high grade molybdenum/rhenium deposit in 2008. A few occurrences of mineralisation were known in the EPM area, however there had been little previous exploration and the area was virtually un-explored.
Initial exploration activities by ActivEX targeted geophysical anomalies identified on figures 7 and 8, in particular magnetic and uranium channel anomalies.
Figure 7. (LHS) Selwyn East area: Regional geological setting shown by airborne magnetic (TMI) Figure 8. (RHS) Regional structure shown by radiometrics (U2/Th)
Principal targets in the area were IOCG and skarn targets similar to Starra and Mt Elliott/Swan respectively and therefore magnetic and radiometric anomalies were investigated. Reconnaissance geology and rock sampling were carried out which quickly highlighted the Heathrow and JFK Gossans. These gossan occurrences had not previously been discovered and occur in an area where strong uranium signature was identified in preliminary work using the magnetic and radiometric surveys data.
The Heathrow area was immediately targeted for further work and a SAM survey was completed over the Heathrow and JFK area followed by Niton and MMI geochemical surveys. The targets are now ready to drill in this area.
Heathrow and JFK The Heathrow and JFK prospects consist of partially outcropping gossans that contain elevated copper in rock chip samples. SAM surveys have defined major north-north-east trending magnetic anomalies over the gossans, suggesting there is significant extent to the prospect (e.g. longer than 600m for Heathrow).
The gossans are interpreted to represent magnetite-rich skarns, hosted by a structural zone.
The SAM survey also highlighted a number of conductive zones on the east side of the grid, which are interpreted to represent a possible black shale linked by thrust faulting.
MMI soil geochemistry was used over the area of interest, which is poorly outcropping but mostly consists of residual soil and sand cover. Anomalous copper (relatively weak) was found to be associated with the Heathrow Gossan and surrounds. Meanwhile, molybdenum showed a startling correlation with the conductivity zones on the eastern side of the grid, in particular the linking structures between the interpreted black shale (note: interpretation of black shale units = major conductors supported by high cadmium values in soil geochemistry). The coincidence of black shale units, cross structures, molybdenum anomalies and conductors is highly encouraging for a Merlin style target in the area.
Figure 9. Heathrow and JFK prospects – rock chip sampling over SAM ground magnetics
As discussed above, there is significant potential Mt Elliot/Swan style skarn mineralisation and Merlin style molybdenum mineralisation within the Selwyn East tenements. Two prospects have been identified at Heathrow and JFK, however the remainder of the area remains relatively underexplored and there is significant scope for additional targets.
The Cloncurry Fault Project includes EPM 17454 (Camel Hill) and EPM 18852 (Robur) covering a region approximately 40km long immediately southeast of Cloncurry. The primary targets are IOCG style copper and gold and skarn style copper within a NNW trending structural corridor dominated by the Cloncurry Fault. ActivEX has concentrated exploration efforts on three main prospects (Robur Mine, Green Monster and Bull Creek) with surface geochemical sampling demonstrating enough potential to recommend further follow up work.
The Camel Hill and Robur tenements are strategically placed along the Cloncurry and Robur Faults which act as conduits for mineralised hydrothermal fluids. The Cloncurry Fault is a regional tectonic contact between the Soldiers Cap Group to the east and the Mary Kathleen Group to the west. It is considered particularly prospective as a splay from the fault which hosts the Great Australia Mine, 10 km north of the project area. In the southern section of the prospect area, the Williams Granite, Saxby Granite and Mt Angelay Granite are all present, providing an alternative source for mineralized fluids. ActivEX is principally targeting IOCG and skarn style mineralisation associated with the significant structures and intrusions.
Located in the north of the Robur tenement, the Robur Mine prospect is an IOCG target with a 1.5 km long surface geochemical copper anomaly. A number rock chip assays have returned high grade copper and gold values up to 14.2% copper and 1.49 g/t gold. One sample assay also returned 38 g/t silver. Most mineralisation at the surface is considered secondary to potential extensive primary mineralisation at depth related to a mineralised granite intrusion.
The Green Monster prospect is a skarn style copper prospect situated in the north of the Camel Hill tenement. It is focused around three small open pit workings spread 70m along a northeast trend exhibiting strong mineralisation of copper minerals and yields rock chip assay values of up to 5.6% copper. Although surface geochemical surveys have defined the copper anomaly to only extend 50m from the workings, the sub-surface extent of mineralisation remains unknown and open to investigation.
The Bull Creek prospect, located in the west of the Camel Hill tenement, is prospective for skarn style copper. Strong mineralization associated with alteration yields rock chip copper values up to 34.7%. Niton surface geochemical sampling and rock chip sampling by ActivEX has confirmed: a relationship between alteration and copper mineralization; and the mineralization and alteration are more laterally extensive then previously known.
These characteristics and their close proximity to the Cloncurry Fault resemble the Green Monster prospect 4km to the north and potential for further copper mineralisation lies between the two prospects.
The 1.5 km long copper surface geochemical anomaly at the Robur Mine prospect indicates potential for significant mineralisation at depth. The structural setting, centered around the Robur Fault, combined with its close proximity to a mineralised igneous fluid source demonstrates the possibility for more extensive IOCG style mineralisation. This potential requires testing with geophysical surveys and drilling.
The Green Monster and Bull Creek prospects reveal skarn style mineralisation in two separate locations along the Cloncurry Fault indicating potential for a 4 km long mineralised corridor along the fault. Further surface geochemical sampling is required to define mineralisation and alteration geochemistry before planning geophysical surveys and drilling.
Figure 10. Cloncurry Fault tenements showing prospects over aeromagnetic image (TMI)
The Bulonga tenement consists of one single tenement, EPM 18053. It holds significant potential for structurally hosted gold and copper mineralisation, especially across the fold hinge of the Bulonga Anticline. A number of prospects host strong gold and copper mineralisation but, at this stage, remain poorly understood and their margins have not been defined. In addition many other anomalous areas have not been properly investigated, meaning there is great potential for further prospect generation within the project.
Figure 11. Bulonga tenement showing prospects over aeromagnetic image (TMI)
ActivEX’s Cloncurry Copper and Gold Project represents a substantial holding within a highly prospective geological terrane, surrounded by a number of major deposits. The area has significant potential for IOCG, skarn, or Merlin-style mineralisation with a variety of targets already identified. These tenements have been notably under-explored given the long standing history of mineral exploration within the region and substantial scope remains to make a major discovery.
Florence Bore North
Florence Bore South #1
Florence Bore South #2