Data release - as updated [made at SA Director of Mines' discretion] : Mount Caroline, Mount Harcus and Pine Ridge (the Musgrave Project). Joint annual reports for the period 1/7/2011 to 31/12/2018.
Published: 28 Feb 1919 Created: 12 Nov 2024 Revised: 12 Nov 2024

Three Exploration Licences spread across the central and eastern Musgrave Ranges are now being explored by NiCul Minerals Limited (a wholly owned subsidiary of PepinNini Minerals Limited) which currently owns 100% of each tenement. The ground held...

Three Exploration Licences spread across the central and eastern Musgrave Ranges are now being explored by NiCul Minerals Limited (a wholly owned subsidiary of PepinNini Minerals Limited) which currently owns 100% of each tenement. The ground held is recognised as being highly prospective for magmatic Ni-Cu sulphide mineralisation formed within layered mafic/ultramafic intrusions of the Mesoproterozoic Giles Complex, with scope for also discovering platinum group metals (PGMs), base metals such as Broken Hill type Pb-Zn-Ag within the Birksgate Complex, and diamonds and precious metals. Exploration activities during 2011-2012 (Year 1 of the licences' joint reporting period) primarily involved conducting both a regional bedrock geochemical vacuum drilling program and a diamond drilling program within the Cooperinna Block of EL 4587 Mount Harcus. In addition, an orientation airborne EM survey using the SkyTEM508 equipment platform was flown over parts of ELs 4587 and 4048 in March 2012 along flight lines 100 m apart [see Env 12365]. No field work was undertaken within EL 4780 during the period. 414 vacuum boreholes totalling 4638.7 m were drilled 300 m apart along north-south traverses spaced 400 m apart, to produce a baseline lithogeochemical dataset. Anomalies of interest were subsequently infill vacuum drilled along traverses orientated normal to the structural framework or strike of lithological units. Such infill drilling was conducted at the Cooperinna East Cu prospect and Byron Ni-Cu prospect. 6 vertical or angled wholly diamond cored drillholes totalling 1426.5 m were completed to obtain firm new information about the basement rocks. Two holes, DD11COP001 and DD11COP002, were designed to elucidate the geological framework for interpreted felsic units that were outlined as potential base metal targets by Rio Tinto Exploration in 1999. As a consequence, no geochemical samples were taken for these two diamond holes. The other four holes, DD11COP003 to DD12COP006, were designed to test coincident geochemical and geophysical anomalies contained within the Cooperinna East prospect. The vacuum drilling identified areas of Ni-Cu anomalism, and the diamond drilling intersected gabbronorite sequences which contained various sulphidic horizons with elevated Ni-Cu content. A number of priority one drill targets were identified within the Cooperinna Block from the SkyTEM508 data. During the 2012-2013 reporting period, all field work was again performed within the Cooperinna Block of EL 4587, and comprised follow-up airborne geophysical surveying, ground geophysical surveying, rock chip geochemical sampling, geological mapping, prospect scale infill vacuum drilling, and diamond cored hole drilling. The airborne geophysical survey of 168 line km was undertaken in July-August 2012 along the western side of the Deering Hills, using the VTEM helicopter borne electromagnetic data acquisition system. Several robust conductive bedrock anomalies were identified, then modelled and drill tested relying directly on data from the VTEM airborne survey and the previously acquired SkyTEM508 airborne survey. Another 11 targets required further investigation by ground based electromagnetic surveying and vacuum geochemical regolith drilling to better resolve their modelled features. 8 of the EM targets were chosen for diamond drill testing. 17 diamond drillholes for a total penetration of 3486.66 m were drilled, however, a small number of priority 1 airborne VTEM targets could not be accessed due to aboriginal heritage protection ground disturbance restrictions arising from proposed work area clearance surveys. Diamond coring of targets generated from the geophysical surveying and regolith geochemical sampling discovered the buried Byron and Yagen mafic intrusive bodies and within them encountered gabbronorite sequences containing various sulphidic horizons having elevated Ni-Cu contents. Abundant disseminated and semi-massive pyrrhotite and pyrite within magmatic mafic lithologies which ingress into brecciated felsic mafic basement granulites confirm the sulphur saturation of the intruded melts, but it appeared that the Cu-Ni-PGE chalcolphile content of the melts had been depleted prior to emplacement. The sulphide accumulations are occasionally positioned adjacent to conductive graphitic in tectonic structures or foliated gneissic sequences, suggesting that there is a structural discordance at the competence contrast between the magmatic intrusion contacts and basement granulite. 6 rock chip samples from the Pegasus prospect, 1 from the Venus prospect and 9 from the Yagen prospect were submitted for whole rock analysis, and 19 drill core and 5 outcrop rock chip samples were submitted to Mason Geoscience for petrographic descriptions and interpretations. The petrological studies showed that the east to south-east trending Yagen intrusion is pyroxenitic to gabbroic in composition, and its Mg numbers range from 83 to 40. All four of the fractionated rocks examined have been pervasively to selectively recrystallised due to subsequent granulite facies metamorphism. The infill vacuum drilling to sample regolith geochemistry and bottomhole sample bedrock lithology mapping was only partially successful, with few recognisable anomalies or definite rock types discernable. It was unclear whether elevated Cu and/or Ni geochemical responses are associated with proximity to sulphide bearing intrusive rocks, or merely reflect the lithochemical response of common late stage aphanitic dolerite dykes (Amata Suite). From comparing the conductive sources intersected as a consequence of following up SkyTEM508 anomalies versus VTEM anomalies, it was tentatively concluded that SkyTEM508 has been more successful in discriminating targets sourced by disseminated to massive sulphide mineralisation, whereas the VTEM anomalies, whilst often containing substantial disseminated sulphide, were predominantly sourced by accumulations of coarse and flaky graphite. During the 2014 reporting period, no field exploration activities were undertaken by NiCul within any of the three project licences. Throughout the period it became increasingly difficult for the company to secure timely assistance from APY Anthropology to facilitate Traditional Owner approval for the commencement of work. PepiNini's previous dealings with Traditional Owner groups had generally reinforced that proper and direct consultations between the proponent company and the Traditional Owner group resulted in satisfactory outcomes for both land access and heritage protection. But increasingly, since 2011, the situation arose where company representatives were being restricted from obtaining access to Traditional Owners to present and discuss proposed exploration activities, through them being able to directly participate in APY's heritage clearance survey processes. For 2014, substantial field exploration activities had been planned to take place across the south-eastern part of EL 5220 (Mount Caroline). Work programme proposals, seeking to gain access approval through receiving Traditional Owner advice and facilitating the conduct of heritage clearance surveys, had been submitted to APY in September 2013. On several occasions the commencement of this survey work was scheduled by APY and then was cancelled at the last minute. Some of the requested heritage clearance surveying was eventually done in July 2014, but only across part of NiCul's proposed work areas : no company representatives were permitted to attend the survey, and the formal report which documented its outcome was not provided to NiCul until September 2014. Perforce engaging meanwhile in separate office-based activity, NiCul entered into a scientific research and development collaboration with the Minerals DownUnder division of the CSIRO, that would involve collecting and interpreting geophysical datasets with a view to mapping regolith and palaeodrainage and underlying bedrock conductors in the subject licence areas. It was hoped that this work would enhance the success of the SA Government's PACE Initiative Theme 3 - "Mineral Exploration Under Cover" and also serve to promote mineral targeting for the Musgrave Project. It was intended to start the data acquisition within the southern part of EL 5220 Mount Caroline, over three Ni-Cu sulphide prospects named Scott, Wandila and Fowler. The mineral potential of these prospects had earlier been highlighted by NiCul following its identification of seven discrete magnetic “bulls-eye” anomalies lying near the intersections of major structural and gravity lineaments, which were interpreted as possibly representing responses arising from prospective mafic intrusive feeder dykes. Plans were formulated with the CSIRO to soon acquire an airborne electromagnetic survey to investigate if any Ni-Cu sulphide mineralisation might exist within and around these high-priority prospects. During the 2015 reporting period, NiCul's exploration activities involved performing a paleomagnetic study of the Caroline intrusion, conducting a heritage clearance survey across the southern portion of EL 5220, conducting a regional bedrock sampling vacuum drilling programme there, and also collecting 2 rock chip samples of sparse outcrop, and relocating the company's containerised field camp to the Central Plains area within EL 5220. No field work was done on ELs 4587 or 4780. The vacuum drilling at Central Plains, of 253 vertical holes totalling 3004 m, which were put in at 100 m - 200 m intervals along 9 north-south orientated regional traverses spaced 1 to 3 km apart, and at 50 m intervals along 6 infill traverses, identified areas of PGE mineralisation in a number of east-west trending mafic dykes, plus a weakly copper anomalous zone. The drilling programme mapped for the first time the main basement subcrop geology in Central Plains, and showed that positive magnetic anomalies are related to iron-rich metasedimentary units belonging to the Birskgate Complex, whereas negative magnetic anomalies relate to retrograde alteration and destruction of primary magnetite that has occurred along structures. In two geophysical domains interpreted to represent basement mafic-ultramafic intrusions similar to the Caroline intrusion, two geochemically anomalous bedrock targets were chosen which it was recommended should be flown with an airborne electromagnetic survey. In general, the highest assay results for copper, nickel and PGEs appeared to be related to mafic granulite dykes of the Amata Dolerite, the youngest igneous intrusions in the area, which genetically post-date the Giles Complex intrusive event and do not form petrologically or volumetrically attractive targets for magmatic Cu- Ni mineralisation. The paleomagnetic study of the Caroline intrusion was managed by James Austin of the CSIRO. The aim of the project was to develop a new geophysical tool to optimise the identification and classification of mafic-ultramafic intrusions of Giles Complex age and affinity, using insights obtained from magnetostratigraphic information contained in regional TMI data. Measurements were made of the magnetic properties from various magmatic zones of the layered Caroline intrusion, to better interpret regional airborne magnetic data from a targeting perspective. These results were used to constrain transformations of the TMI data recorded over NiCul's tenements, utilising a range of pre-determined magnetisation directions generated by measurements taken from drill cores targeting the layers of the Caroline intrusion. Magnetic modelling and inversions of the transformed anomaly datasets were then undertaken, in order to assist in regional target generation. The study evaluated 20 magnetic anomalies, 16 of which are located within EL 5220, and ranked them : two anomalies were given priority 1 status as representing likely layered intrusions. During the 2016 reporting period, exploration activities included three airborne electromagnetic (AEM) surveys over both tenements, interpretation of the geophysical survey results, planning of follow up exploration work, and the continued community engagement to identify the Traditional Owners of the southern area of EL 5220. The first AEM survey was flown in conjunction with the CSIRO, the South Australian Department of Development (DSD) and the Geoscience Australia (GA) as part of regional AEM coverage of the Musgrave Province. The second and third surveys were opportunistically flown by NiCul Minerals Ltd. to increase coverage and infill interesting areas and targets defined during the regional survey. The Regional Survey was flown by CGG using the airborne fixed-wing Time-Domain electromagnetic “Tempest” system. The survey covered the majority of EL 5220 'Mt Caroline' and all the Mt Tietkins block of EL5735. The western infill surveys were flown by CGG using the airborne fixed-wing Time-Domain electromagnetic “Tempest” system and the EL5220 infill survey was flown by SkyTEM utilizing the helicopter mounted SkyTEM516 system. A paleo-magnetic study of the Mouth Caroline intrusion was undertaken by James Austin of CSIRO, with the aim of the project to develop a new geophysical tool to optimise the identification of mafic-ultramafic intrusions of Giles age and affinity in regional TMI data [See included report]. During the 2017 reporting period, exploration activities during this reporting period have involved regional and infill data processing and inversions modelling of recently flown AEM Surveys. PepinNini Lithium (PNN) in collaboration with CSIRO are applying statistical modelling (threshold/machine learning approaches) for predicting the regolith cover thickness across the Musgrave Region, using the inverted regional and infill AEM data sets flown in late 2016. This is the first time such an approach has been applied to this type of data in this part of Australia. The aim is to generate a regolith-unweathered basement boundary, and map of regolith thickness for the Musgrave Province; identifying the location of buried palaeovalley systems that can impede exploration for buried ore systems. This will ultimately allow PNN to optimise its exploration program especially its drill targeting. No field work was carried out during the reporting period based on community and logistic issues beyond the control of the Company; resulting in the Heritage Clearance Survey over the southern area of EL5220 being rescheduled on numerous occasions and ultimately being postponed indefinitely. During the 2018 reporting period. exploration activities included the continued assessment and review of regional and infill airborne geophysical data and regional geological analysis. No field work was carried out during the reporting period due to community and logistic issues beyond the control of the Company.

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About this record

Record No mesac27919
Topic Geoscientific Information
Type of Resource Document
Category Type
Document Type Mineral Company Report - Mineral Exploration
Contributor Mason Geoscience Pty Ltd;GroundProbe Geophysics Pty Ltd;Geotech Ltd;NewExCo Services Pty Ltd;Southern Geoscience Consultants Pty Ltd;CSIRO Mineral Resources Flagship. Magnetics and Gravity Group
Sponsor PepinNini Minerals Ltd
Tenement
Tenement Holder NiCul Minerals Ltd
Operator NiCul Minerals Ltd
Geological Province
Mine Name Cooperinna East prospect;Byron prospect;Byron South prospect;Bondi prospect;Yagen prospect;Venus prospect;Alma prospect;Deception prospect;Cactus prospect;Pegasus prospect;Scott prospect;Wandila prospect;Fowler prospect
Stratigraphy
Commodity
Notes
Notes: This release to the public of the subject mineral exploration data, namely, company data which was acquired more than 5 years ago, is being done by DMITRE/DPC/DEM in accord with the provisions of Section 77D of the Mining Act 1971 and...

Notes: This release to the public of the subject mineral exploration data, namely, company data which was acquired more than 5 years ago, is being done by DMITRE/DPC/DEM in accord with the provisions of Section 77D of the Mining Act 1971 and Regulation 88 of the Mining Regulations 2011. Includes: - Williams, T., 17/5/2013. Petrological and geochemical evaluation of the Yagen intrusion, Cooperinna (PepiNini Minerals internal memorandum). In Appx 8 of Musgrave Project licences' second joint annual report to 31/12/2013. 12 pages, 5 fig, 3 plates; - Austin, J.R., 28/1/2016. Report on magnetic properties of the Ngunala (Mount Caroline) intrusion, Musgrave Block, SA, and implications for regional Ni-Cu-PGE exploration (CSIRO Magnetics and Gravity Group report for PepinNini Minerals). Appx 2 of Musgrave Project licences' fourth joint annual report to 31/12/2015. 74 pages, 50 figures, references, 2 tables. - Austin, J.R. 3/5/2016. Magnetic Properties of the Ngunala (Mount Caroline) Intrusion, Musgrave Block, SA. Implications for regional Ni-Cu-PGE exploration. CSIRO – Magnetics & Gravity Group, Mineral Resources Flagship. Appx. 2 to annual technical report to 31st December 2016. - Blundell, K. 2016. Musgraves Project - September – October AEM Surveys Interpretation Report. Appx. 3 to annual technical report to 31st December 2016. Geographic Locality: Musgrave Ranges;Mann Ranges;Deering Hills;Hanging Knoll;Mount Caroline;Anangu Pitjantjatjara Yankunytjatjara Lands;2012 Musgrave Aerial EM (SkyTEM) Survey;2012 Cooperinna Block Aerial EM (VTEM) Survey;2012 Cooperinna Block Aerial Magnetic Survey Doc No: Env 12314 Drillhole: VCP001 - VCP421;DD11COP001 - DD11COP006;VCP422 - VCP646;DD12COP007 - DD12COP016;DD13COP017 - DD13COP024;VCS0001 - VCS0253

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Language English
Metadata Standard ISO 19115-3

Citations

Use constraints License
License Creative Commons Attribution 4.0
Persistent identifier https://pid.sarig.sa.gov.au/document/mesac27919
Citation Williams, T.;Mason, D.R.;Reid, J.;Tod, A.;Clifford, P.J.;Moschuk, L.;Ebner, N.;Austin, J.R.;Galloway Warland, N. 1919. Data release - as updated [made at SA Director of Mines' discretion] : Mount Caroline, Mount Harcus and Pine Ridge (the Musgrave Project). Joint annual reports for the period 1/7/2011 to 31/12/2018. Mineral Company Report - Mineral Exploration
https://pid.sarig.sa.gov.au/document/mesac27919

Technical information

Status
Maintenance and Update Frequency
Geographic Reference GDA2020 (EPSG:7844)
Geo bounding box {"type":"Polygon","coordinates":[[[129,-27],[135.5,-27],[135.5,-26],[129,-26],[129,-27]]]}
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