Cu and Cu-Au deposits: identifying fingerprints and footprints using trace element geochemistry

Project Partners: Anglo American Exploration, Glencore, South32, Geological Survey Queensland

Project Team: Associate Professor Ioan Sanislav, Dr Avish Kumar, Elizabeth Morejon, Gabriel Cellier

Exploring for mineral deposits is costly, time-consuming and high risk, particularly in areas of cover. However, the search for deposits can be aided by using data obtained from minerals within the much larger alteration haloes that commonly occur around areas of hydrothermal mineralisation.  In-situ mineral chemistry collected from minerals associated with alteration and mineralisation has emerged as a technique with potential for fingerprinting and mapping the footprints of mineral deposits.  The application of this technique is currently limited by to a lack of well-constrained mineral chemistry data and the time and costs of obtaining the analyses.

This project aims to:

• assess the footprint, fingerprint and vectoring potential of chalcopyrite, pyrite and albite from the Cu and Cu-Au deposits in the Mount Isa region;
• develop analytical protocols for in-situ mineral chemical analysis to deliver results rapidly and at a reduced cost.

Mineral analyses will carried out using the recently installed JCU state-of-the-art microprobe to collect in-situ trace element chemistry from co-existing chalcopyrite, pyrite and albite in well characterised sample suites from deposits in the Mount Isa region.

Critical minerals in northeast Queensland

Project Partners: Geological Survey Queensland

Project Team: Dr Ioan Sanislav, Prof. Paul Dirks, Dr Vladimir Lisitsin, Avish Kumar, Alex Edgar, Jonghyun Lee

Critical metal mineralization recognized in northeast Queensland includes Ni, Co and Sc associated with laterites developed on altered ultramafic complexes, and In associated with intrusion-related tin, tungsten and polymetallic deposits.

This project aims to:

• Investigate unexplored ultramafic complexes in northeast Queensland to improve the understanding of their settings, characteristics and potential to host mineralization.
• Investigate the characteristics and distribution of In in selected Sn and polymetallic deposits to identify factors controlling the location and formation of In mineralization.
• Investigate the relationship between late Palaeozoic magmatic activity and critical mineral occurrences in northeast Queensland.

Stable metal isotopes in the alteration halo of an epithermal Au-Ag deposit

Project team: Helen McCoy-West, Alex McCoy-West

This project is a pilot study to constrain stable isotope systematics during hydrothermal alteration associated with the formation of an epithermal Au-Ag deposit.
Stable metal isotope systematics are process dependent, and therefore can provide additional information about processes occurring during the formation of a hydrothermal ore deposit, such as changes in the physical and chemical properties of the fluid(s) involved with host rock alteration and ore deposition. Analysis of a variety of different stable metal isotopes utilises the different properties and behaviours of different metals within a hydrothermal system. The project will test whole rock samples of the host rock (varying from relatively fresh to intensely altered) from a relatively simple epithermal deposit. This project with determine if any of the isotopes studied are suitable as exploration tracers to fingerprint this type of ore deposit. The objective for future research projects is then to apply the results to studies of more complex and/or other types of hydrothermal ore deposits.

Fingerprinting environmentally sustainable ores using neodymium isotopes

Project Partners: Queensland Department of Resources, University of Queensland

Project Team: Alex McCoy-West, Anne Kaufmann, Brandon Mahan, Helen McCoy-West

The rare earth elements (REE) are a critical resource as the world transitions to an energy system dominated by green energy. However, current extraction methods rely on strong acid leaching, which has the potential to create environmental contamination. Alternative REE extraction methodologies, including phyto‐extraction (using plants) and bacteria induced bioleaching are currently being investigated. This project aims to utilise radiogenic and stable neodymium isotopes to characterise the isotopic fractionations induced during different REE extraction techniques. This isotopic fingerprinting will provide a method to verify more sustainably generated REE concentrates, enabling the Australian REE industry to be positioned as a world leading environmental producer.

Marine sediment geochemical survey: Coastal waters of southeastern Brazil

Project Partners: Hydrobiology Pty Ltd, University of Melbourne

Project Team: Alex McCoy-West, Sminto Augustine, Brandon Mahan

This project involves comprehensive geochemical fingerprinting of sediments from a marine environment to trace the potential distribution of exogenous components from a tailings dam failure. JCU is leading the systematic multi-instrument (XRD, XRF, ICP-MS, MC-ICP-MS) geochemical and isotopic characterization of approximately 200 samples. This includes quantifying the mineralogy, major, trace and volatile element concentration analysis, coupled with high-precision O-Sr-Nd-Fe isotope composition analyses.

Understanding rare earth element ion adsorption clay deposit formation and element mobility

Project Team: Alex McCoy-West, Samantha Russo, Helen McCoy-West, Dr Ignacio Gonzalez-Alvarez

Project Partners: CSIRO, Lynas Resources, Classic Minerals

Interest in ion adsorption clay deposits has surged recently as a result of the easier recovery of REE, and lower environmental impacts associated with this process. This project aims to better understand IACD through applying the mineral systems approach, as well as characterise their stable isotope footprint and optimising sequential extraction methodologies.

Linking continental emergence and climatic evolution on the Early Earth

Project Partners: Geological Survey of Western Australia

Project Team: Alex McCoy-West, Mark Nestmeyer, Pratyush Raj, Dr David Martin

This project aims to constrain the timing and extent to which the continents were emergent (above sealevel) at different times in Earth’s history and its impact on climatic evolution, which remains poorly understood. Continental emergence was a pivotal moment in the development of our habitable planet, because it controls the influx of bioessential elements (like phosphorus) to the oceans. Using innovative geochemical techniques, expected outcomes of this work include a detailed record of changes in ocean chemistry and a time integrated model of the amount of emergent crust on the early Earth. Documenting the impact of changes in the solid Earth on the evolution of life is of the highest interest to society in Australia and abroad.

Zircon geochemistry as a vector to mineralisation in the Geita Gold deposits, Tanzania

Project Partners: Geita Mine (AngloGold Ashanti)

Project Leader: Dr Ioan Sanislav

Potential for sediment-hosted base metal mineralisation in the southern part of the Western Succession, Mount Isa Inlier

Project Partners: Geoscience Australia

Project Leader: Dr Ioan Sanislav