Other Prospects

Nepean South Nickel Project E15/1702:

The Nepean South Project is located directly south and along strike from the historical Nepean Nickel Mine (see Figure 1 below), owned by Auroch Minerals Limited (ASX: AOU). Nepean was the second producing nickel mine in Australia, producing 1,108,457t of ore between 1970 and 1987 for 32,202t of nickel metal at an average recovered grade of 3.0% Ni1.


 Figure 1: Nepean South Nickel Project interpreted geology

The Nepean South tenement, E15/1702, incorporates an approximately 10km strike length belt of greenstone lithologies, including Kambalda-style komatiites, flanked by granites, with significant nickel sulphide mineralisation potential. Komatiite hosted nickel deposits of the Kambalda style are generally associated with footwall embayments in channelised ultramafic flows where, if sulphur saturated, nickel sulphides accumulate and, in some cases, e.g. Nepean nickel deposit, form massive sulphide deposits.

Historical shallow RAB drilling in the Nepean South area was completed by Mincor Resources NL (Mincor) (E15/884, 2007-2012) with significant drilling results1 including:

NRB048: 6m @ 1.84% Ni and 0.02% Cu from 18m

The association of high nickel values with elevated copper, particularly in NRB048 (6m @ 1.84% Ni and 0.02% Cu), indicates that the Nepean South Project is highly prospective for the discovery of massive nickel sulphides in primary lithologies.

RAB drilling was completed to only very shallow depths, on average only 42m from surface, with many holes drilled to even shallower depths. Deeper potential in the vicinity of the shallow RAB intersections will be targeted for the discovery of massive nickel sulphides.

To assist drill-targeting, an initial exploration program is planned at the Nepean South project comprising an EM and magnetics survey (airborne or ground-based) across the entire strike length of the prospective ultramafic sequence. Drilling will then follow, to test primary footwall embayments in the vicinity of identified komatiites, associated with elevated RAB geochemistry and/or EM anomalies to target nickel sulphides at depth.

Cave Hill Nickel Project

The Cave Hill Project consists of three Exploration Licence applications (EL15/1843, EL 15/1844 and EL 15/1845) that include two structural/magnetic trends of interest for potential nickel sulphide deposits (see Figure 2):

  • Two applications (E15/1843 and E 15/1844) covering a 50km strike-length magnetic trend south of the historical Nepean Mine and Metals’ Nepean South tenement E15/1702, and,
  • One application (EL 15/1845) south of the Queen Victoria Rocks nickel sulphide prospect, that covers a strong magnetic target.

All the magnetic targets are concealed by shallow cover. The primary targets within the tenement package are potentially sulphur-saturated ultramafic rocks hosting nickel sulphides, along strike from known nickel sulphide occurrences (e.g., Queen Victoria Rocks prospect, Nepean nickel deposit).

The magnetic features covered by E15/1843 and E15/1844 show a similar magnetic pattern to the outcropping Nepean South greenstone belt. This magnetic pattern infers greenstone with magnetic zones (potentially ultramafics) and weaker magnetic zones (potentially mafics), with coincident gravity imagery also indicating subtle gravity highs that may be remnant greenstone.

Application E15/1845 is located southwest and on the western side of a regional dome from the Queen Victoria Rocks nickel sulphide occurrence (Figure 2). A strong northwest trending magnetic feature is the primary target for investigation for remnant greenstone/ultramafic and/or magnetic BIF horizons.

Based on examination of previous airborne magnetic and gravity data, historic exploration activity and neighbouring mineral resources, the application areas will primarily be targeted for buried nickel (Ni) sulphide mineralisation associated with channelised, high-MgO, ultramafics.

Review of historical exploration and GSWA airborne magnetic data within the tenement application areas suggests they remain insufficiently tested by previous explorers for remnant mafic/ultramafic greenstones.

The exploration program on these tenements will include detailed airborne and/or ground magnetics and gravity surveys to detail the anomalies and define targets for channelised, nickel-sulphide bearing ultramafics. This would be followed by soil /auger geochemical sampling and targeted aircore drilling of coincident magnetic/gravity features and anomalies. RC drilling to follow based on lithologies intersected and anomalous nickel +/- copper anomalism.
 

 
Figure 2: Cave Hill Nickel Project tenements with Nepean (AOU) and Nepean South (MLS) Projects

Ngalia Uranium Project, Northern Territory:

Under the Acquisition of Chalco the Company holds an 80% interest in the Ngalia Uranium Project which comprises two exploration licence applications (EL32829 and EL32864) located within the highly prospective Ngalia Basin in the southwestern Northern Territory (NT) (see Figure 3 below). The Ngalia Basin has been extensively explored for uranium mineralisation in the 1970s and 1980s with several significant uranium resource projects identified along the northern extent of the basin.

The Ngalia ‘Dingo’ tenement EL32829 is highly prospective for tabular, sandstone - hosted, uranium–vanadium (U-V) deposits of Carboniferous age. The targeted deposits are fluvial, sandstone-hosted U-V deposits which are analogous to the nearby Bigrlyi U-V deposit (Figure 3).

Based on examination of previous airborne magnetic and gravity data, historic exploration activity and neighbouring mineral resources, the application areas will primarily be targeted for buried nickel (Ni) sulphide mineralisation associated with channelised, high-MgO, ultramafics.

Review of historical exploration and GSWA airborne magnetic data within the tenement application areas suggests they remain insufficiently tested by previous explorers for remnant mafic/ultramafic greenstones.

The exploration program on these tenements will include detailed airborne and/or ground magnetics and gravity surveys to detail the anomalies and define targets for channelised, nickel-sulphide bearing ultramafics. This would be followed by soil /auger geochemical sampling and targeted aircore drilling of coincident magnetic/gravity features and anomalies. RC drilling to follow based on lithologies intersected and anomalous nickel +/- copper anomalism.
 

Figure 3: Ngalia Basin, project locations and geology of Bigrlyi uranium-vanadium deposit

The Ngalia ‘Lake Lewis’ tenement EL32864 is considered prospective for calcrete style uranium-vanadium mineralisation hosted by palaeo-channels, analogous to the neighbouring Napperby and Cappers uranium resources.

The Dingo tenement EL32829 is predominantly outcropping Ngalia Basin units, including the highly prospective Mount Eclipse Sandstone, which is folded in the Patmungala Syncline. In the southern part of the tenement the Mt Eclipse Sandstone horizon is covered by flat lying Palaeozoic sediments, however drainage anomalies with elevated uranium highlight the prospectivity of the underlying units.

Initial exploration for sandstone-hosted, uranium–vanadium deposits in the Dingo project would focus on potential extensions of identified prospects and will include detailed magnetics to trace west-north-west trending structures, and further, detailed, geochemistry to better define and extend historical geochemical anomalies (U-V and Cu-Au) in the NE corner of the tenement, in an area of structural complexity. Drilling targets will be initially followed up with grid-based aircore drilling prior to deeper RC drilling to test anomalies and key contacts.

The Lake Lewis ELA32864 lies immediately along strike to the southwest of the Napperby Uranium Deposit, which was discovered by CRA Exploration in the 1970s and has a current, JORC 2012, Inferred Resource, re-estimated by Core Energy, of 9.54Mt at 382ppm U3O8 for 8.03 Mlb of contained U3O8 (at a 200 ppm U3O8 cut-off).

The Napperby deposit is hosted by palaeo-drainages incised into the Palaeo-Proterozoic to Meso-Proterozoic basement and filled with 10m to 100m of Recent clastic material. Uranium mineralisation is hosted by partially carbonaceous sands and clays in the palaeo-drainage fill, that may have acted as redox fronts. The Napperby deposit lies immediately below and to a lesser extent within a calcrete layer overlying the sands and clays as coatings, disseminations, pellets and blobs (‘nuggets’) of carnotite up to 5 cm long.

Examination of previous radiometrics, Aster imagery and correlation with the neighbouring Napperby Mineral Resource3 indicates that the Lake Lewis EL32864 is highly prospective for shallow calcrete style uranium - vanadium mineralization associated with palaeo-drainages close to the confluence with Lake Lewis. Radiometric ratios and limited review of historical exploration indicates uranium enrichment within this zone, that remains insufficiently tested by previous explorers

Detailed geophysical and geochemical programs will target the interpreted projections of this zone from the position of the radiometric anomalies and to the north, projected under Lake Lewis. Aircore/sonic drilling of key targets identified will follow.

Carrara Project E32693, Northern Territory:

Chalco also holds exploration licence (EL) 32693, granted on the 26 October 2021, which is located approximately 340 km east northeast of Tennant Creek and 1000 km SE of Darwin (see Figure 4).

The Carrara tenement is considered highly prospective for:

  • Iron Oxide Copper Gold (IOCG) mineralisation of the ‘Tennant Creek’ style, within extensions of the Tennant East Belt.
  • Zinc-lead-silver (SEDEX) massive sulphide deposits or sedimentary copper deposits of the McArthur River-Mount Isa provinces (e.g., Century, McArthur River, George Fisher, Mount Isa copper-lead-zinc and Lady Loretta), within the buried Lawn Hill Platform.

Geoscience Australia (GA) have highlighted the prospectivity of the Tennant East Belt that extends from Tennant Creek, east towards the Mt. Isa Block (Figure 4). The southern and eastern boundaries of the tenement are dominated by a significant northeast-trending, magnetic high feature that is interpreted to represent the eastern equivalent to the Warramunga Formation, the host to the high-grade Tennant Creek style Iron-Oxide Copper Gold (IOCG) deposits.

Near surface within EL32693 are the Georgina Basin sediments, that are interpreted to unconformably overlie the prospective Palaeo-Proterozoic units at depth. The area is poorly explored, particularly for minerals within the basement. There are several stratigraphic holes drilled in the area by GA in collaboration with the Northern Territory Geological Survey (NTGS) that, in combination with seismic data, reveal that the Tennant East Belt lies at only moderate depth below the clastic sediment filled basins. The Mt Isa Province units are interpreted to lie at greater depth to the south of the faulted contact with the Lawn Hill Platform.

Initial exploration on EL32693 will focus on acquiring detailed magnetic and gravity data in order to detect buried Warramunga Formation and target Tennant Creek style, high-grade, IOCG deposits that will then be tested by drilling, focused on discrete and coincident magnetic and gravity highs.

Initial exploration for Lawn Hill Platform/Mt Isa Province mineralisation would focus on modeling and interpretation of geophysical data sets to target coincident gravity/magnetic features that correlate with basement highs interpreted from seismic data in the area. Key stratigraphic holes, potentially in collaboration with the NTGS and/or GA, would then test these basement highs for mineralisation both within the overlying Georgina Basin and within the underlying Lawn Hill Platform/Mt Isa Province units.

Figure 4: Mineral Potential map with Tennant East Belt and Lawn Hill/Mt Isa Province and EL32693

 

 

 

 

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