<div>Australian sediment-hosted mineral systems are important sources of base metals and critical minerals that are vital to delivering Australia’s low-carbon economy. In Australia, sediment-hosted resources account for ~82% and ~86% of the total zinc (Zn) and lead (Pb) resources respectively. Given their significance to the Australian economy, four national-scale mineral potential models for sediment-hosted Zn-Pb mineral systems have been developed: clastic-dominated siliciclastic carbonate, clastic-dominated siliciclastic mafic, Mississippi Valley-type and Irish-type. In addition to the potential for Zn-Pb mineralisation, the uncertainty related to data availability has been examined. The mineral potential models were created using a mineral systems-based approach where mappable criteria have been used to assess the prospectivity of each system. Each model has been derived from a large volume of precompetitive geoscience data. The clastic-dominated siliciclastic carbonate mineral potential model predicts 92% of known deposits and occurrences within 15.5% of the area, the clastic-dominated siliciclastic mafic mineral potential model predicts 85% of deposits and occurrences within 27% of the area, and the Mississippi Valley-type mineral potential model predicts 66% of known deposits and occurrences within 31% of the area. Each model successfully predict the location of major sediment-hosted Zn-Pb deposits while highlighting new areas of elevated prospectivity in under-explored regions of Australia, reducing the exploration search space by up to 85% for sediment-hosted Zn-Pb mineral systems.</div>

<div>Long-period magnetotelluric (MT) data from the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP), collected as part of Geoscience Australia’s Exploring for the Future program with contributions from the Northern Territory Geological Survey and the Geological Survey of Queensland, provide important first-order information for resolving large-scale lithospheric architecture and identifying the broad footprint of mineral systems in northern Australia. Large-scale crust/mantle conductivity anomalies map pathways of palaeo-fluid migration which is an important element of several mineral systems. For example, the Carpentaria conductivity anomaly east of Mount Isa and the Croydon, Georgetown to Greenvale conductivity anomaly are highly conductive lithospheric-scale structures, and show spatial correlations with major suture zones and known mineral deposits. These results provide evidence that some mineralisation occurs at the gradient of or over highly conductive structures at lower crustal and lithospheric mantle depths, which may represent fertile source regions for mineral systems. These observations provide a powerful means of highlighting prospective greenfield areas for mineral exploration in under-explored and covered regions.</div><div><br></div><div>Higher resolution scale-reduction MT surveys refine the geometry of some conductive anomalies from AusLAMP data, and investigate whether these deep conductivity anomalies link to the near surface. These links may act as conduits for crustal/mantle scale fluid migration to the upper crust, where they could form mineral deposits. For example, data reveals a favourable crustal architecture linking the deep conductivity anomaly or fertile source regions to the upper crust in the Cloncurry region. In addition, high-frequency MT data help to characterise cover and assist with selecting targets for drilling and improve the understanding of basement geology.</div><div><br></div><div>These results demonstrate that integration of multi-scale MT surveys is an effective approach for mapping lithospheric-scale features and selecting prospective areas for mineral exploration in covered terranes with limited geological knowledge.</div><div><br></div><div>Some models in this presentation were produced on the National Computational Infrastructure, which is supported by the Australian government. Abstract presented to the Australian Institute of Geoscientists – ALS Friday Seminar Series: Geophysical and Geochemical Signatures of Queensland Mineral Deposits October 2023 (https://www.aig.org.au/events/aig-als-friday-seminar-series-geophysical-and-geochemical-signatures-of-qld-mineral-deposits/)

<div>The production of rare earth elements (REEs) is critical to the global transition to a low carbon economy. Carbonatites represent a significant source of REEs, both domestically within Australia, as well as globally. Given their strategic importance for the Australian economy, a national mineral potential assessment has been undertaken as part of the Exploring for the Future program at Geoscience Australia to evaluate the potential for carbonatite-related REE (CREE) mineral systems. Rather than aiming to identify individual carbonatites and/or CREE deposits, the focus of the mineral potential assessment is to delineate prospective belts or districts within Australia that indicate the presence of favourable criteria, particularly in terms of lithospheric architecture, that may lead to the formation of a CREE mineral system.</div><div><br></div><div>This study demonstrates how national-scale multidisciplinary precompetitive geoscience datasets can be integrated using a hybrid methodology that incorporates robust statistical analysis with mineral systems expertise to predictively map areas that have a higher geological potential for the formation of CREE mineral systems and effectively reduce the exploration search space. Statistical evaluation of the relationship between different mappable criteria that represent spatial proxies for mineral system processes and known carbonatites and CREE deposits has been undertaken to test previously published hypotheses on how to target CREE mineral systems at a broad-scale. The results confirm the relevance of most criteria in the Australian context, while several new criteria such as distance to large igneous province margins and distance to magnetic worms have also been shown to have a strong correlation with known carbonatites and CREE deposits. Using a hybrid knowledge- and data-driven mineral potential mapping approach, the mineral potential map predicts the location of known carbonatite and CREE deposits, while also demonstrating additional areas of high prospectivity in regions with no previously identified carbonatites or CREE mineralisation.</div> Presented at the AusIMM Critical Minerals Conference 2023.

The Mineral Potential web service provides access to digital datasets used in the assessment of mineral potential in Australia. The service includes maps showing the potential for sediment-hosted base metal mineral systems in Australia.

<div>Sediment-hosted copper (Cu) mineral systems are important sources of base metals and critical minerals such as cobalt that are vital to delivering Australia’s low-carbon economy. In Australia, sediment-hosted Cu resources account for ~11% of the total Cu resources. Given their significance to the Australian economy, national-scale mineral potential models for sediment-hosted Cu have been developed. In addition to the potential for sediment-hosted Cu mineralisation, the uncertainty related to data availability has been examined. Three mineral potential</div><div>models derived from the combination of two mineral systems have been derived from a large volume of precompetitive geoscience data combined with mineral systems expertise, each using a different combination of input maps to assess the influence of incomplete data on the results. The mineral potential models successfully predict the location of major sediment-hosted stratiform Cu and Mount Isa-type Cu deposits while highlighting new areas of elevated prospectivity in under-explored regions of Australia, reducing the exploration search space</div><div>by up to ~84%.</div>

<div>The production of rare earth elements is critical for the transition to a low carbon economy. Carbonatites (&gt;50% carbonate minerals) are one of the most significant sources of rare earth elements (REEs), both domestically within Australia, as well as globally. Given the strategic importance of critical minerals, including REEs, for the Australian national economy, a mineral potential assessment has been undertaken to evaluate the prospectivity for carbonatite-related REE (CREE) mineralisation in Australia. CREE deposits form as the result of lithospheric- to deposit-scale processes that are spatially and temporally coincident.</div><div><br></div><div>Building on previous research into the formation of carbonatites and their related REE mineralisation, a mineral system model has been developed that incorporates four components: (1) source of metals, fluids, and ligands, (2) energy sources and fluid flow drivers, (3) fluid flow pathways and lithospheric architecture, and (4) ore deposition. This study demonstrates how national-scale datasets and a mineral systems-based approach can be used to map the mineral potential for CREE mineral systems in Australia.</div><div><br></div><div>Using statistical analysis to guide the feature engineering and map weightings, a weighted index overlay method has been used to generate national-scale mineral potential maps that reduce the exploration search space for CREE mineral systems by up to ∼90%. In addition to highlighting regions with known carbonatites and CREE mineralisation, the mineral potential assessment also indicates high potential in parts of Australia that have no previously identified carbonatites or CREE deposits.</div><div><br></div><div><b>Citation: </b>Ford, A., Huston, D., Cloutier, J., Doublier, M., Schofield, A., Cheng, Y., and Beyer, E., 2023. A national-scale mineral potential assessment for carbonatite-related rare earth element mineral systems in Australia, <i>Ore Geology Reviews</i>, V. 161, 105658. https://doi.org/10.1016/j.oregeorev.2023.105658</div>

Magnetotelluric (MT) data allow geoscientists to investigate the link between mineralisation and lithospheric-scale features and processes. In particular, the highly conductive structures imaged by MT data appear to map the pathways of large-scale palaeo-fluid migration, which is an important element of several mineral systems. New data were collected as part of the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) under Geoscience Australia Exploring for the Future (EFTF) program in northern Australian. We use this dataset to demonstrate that the MT method is a valuable tool for mapping lithospheric-scale features and for selecting prospective areas for mineral exploration. Our results image a number of major conductive structures at depths up to ~200 km or deeper in the survey region, for example, the Carpentaria Conductivity Anomaly in east of Mount Isa; and the Tanami Conductive Anomaly along the Willowra Suture Zone. These significant anomalies are lithospheric- scale highly conductive structures, and show spatial correlations with major suture zones and known mineral deposits. These results provide important first-order information for lithospheric architecture and possible large footprint of mineral systems. Large-scale crustal/mantle conductivity anomalies mapping fluid pathways associated with major sutures/faults may have implications for mineral potential. These results provide evidence that some mineralisation occurs at the gradient of or over highly conductive structures at lower crustal and lithospheric mantle depths. These observations provide a powerful means of highlighting greenfields for mineral exploration in under-explored and covered regions.

<div>Mineral exploration and development involves the selection of potential projects which must be evaluated across disparate characteristics. However, the distinct metrics involved are typically difficult to reconcile (e.g. geological potential, environmental impact, jobs created, value generated, etc.). Separate stakeholders—with different goals and attitudes—will reasonably differ in their preferences as to which categories to prioritize and how much weight to give to each. These conflicting preferences can obscure optimal outcomes and confound project selection.</div><div><br></div><div>In this presentation, we will discuss how early-stage exploration decisions can be treated as multi-criteria optimization problems. We show how this approach can be used to effectively evaluate and communicate competing criteria, and locate regions that perform best under a range of different metrics. We then outline a mapping framework that identifies regions that perform best in terms of geological potential, economic value and environmental impact and demonstrate this approach in a real-word example that highlights new exploration targets in the Australian context. Abstract presented at the American Geophysical Union (AGU) Fall Meeting 2023 (AGU23) https://www.agu.org/fall-meeting

<div><strong>Output type: </strong>Exploring for the Future Extended Abstract <strong> </strong></div><div><br></div><div><strong>Short abstract: </strong>There is an increased international focus on achieving high environmental, socio-economic, and governance (ESG) outcomes within mineral supply chains, in addition to delivering positive economic results. Mineral exploration and development projects must balance these disparate objectives to the satisfaction of separate stakeholders. However, the challenge of reconciling distinct preferences can obscure viable outcomes and confound project selection, particularly in the early stages of project development. Here, we discuss how such investment decisions can be treated as multicriteria optimization problems. In appraising the pre-competitive potential for nickel sulphide developments, we show how this approach can be used to effectively evaluate competing objectives and to locate regions that perform best under a range of different metrics. We outline a mapping framework that identifies Australian regions that optimally balance geological potential, economic value, and environmental impact. Our workflow creates a new capability within Australia to incorporate high-level, holistic information into the earliest stages of exploration. While this abstract focuses on mineral exploration, the modelling could be extended to other Australian resource development applications. Importantly, our results further underscore the need to compile baseline ESG datasets across Australia to help drive sustainable exploration decisions.</div><div><br></div><div><strong>Citation:</strong> Walsh S.D.C., Haynes M.W. &amp; Wang C., 2024. Multicriteria resource potential mapping: balancing geological, economic &amp; environmental factors. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts. Geoscience Australia, Canberra. https://doi.org/10.26186/149250</div>

The Mineral Potential web service provides access to digital datasets used in the assessment of mineral potential in Australia. The service includes maps showing the potential for sediment-hosted base metal mineral systems in Australia.