We collected 38 groundwater and two surface water samples in the semi-arid Lake Woods region of the Northern Territory to better understand the hydrogeochemistry of this system, which straddles the Wiso, Tennant Creek and Georgina geological regions. Lake Woods is presently a losing waterbody feeding the underlying groundwater system. The main aquifers comprise mainly carbonate (limestone and dolostone), siliciclastic (sandstone and siltstone) and evaporitic units. The water composition was determined in terms of bulk properties (pH, electrical conductivity, temperature, dissolved oxygen, redox potential), 40 major, minor and trace elements as well as six isotopes (δ18Owater, δ2Hwater, δ13CDIC, δ34SSO4=, δ18OSO4=, 87Sr/86Sr). The groundwater is recharged through infiltration in the catchment from monsoonal rainfall (annual average rainfall ~600 mm) and runoff. It evolves geochemically mainly through evapotranspiration and water–mineral interaction (dissolution of carbonates, silicates, and to a lesser extent sulfates). The two surface waters (one from the main creek feeding the lake, the other from the lake itself) are extraordinarily enriched in 18O and 2H isotopes (δ18O of +10.9 and +16.4 ‰ VSMOW, and δ2H of +41 and +93 ‰ VSMOW, respectively), which is interpreted to reflect evaporation during the dry season (annual average evaporation ~3000 mm) under low humidity conditions (annual average relative humidity ~40 %). This interpretation is supported by modelling results. The potassium (K) relative enrichment (K/Cl mass ratio over 50 times that of sea water) is similar to that observed in salt-lake systems worldwide that are prospective for potash resources. Potassium enrichment is believed to derive partly from dust during atmospheric transport/deposition, but mostly from weathering of K-silicates in the aquifer materials (and possibly underlying formations). Further studies of Australian salt-lake systems are required to reach evidence-based conclusions on their mineral potential for potash, lithium, boron and other low-temperature mineral system commodities such as uranium. <b>Citation:</b> P. de Caritat, E. N. Bastrakov, S. Jaireth, P. M. English, J. D. A. Clarke, T. P. Mernagh, A. S. Wygralak, H. E. Dulfer & J. Trafford (2019) Groundwater geochemistry, hydrogeology and potash mineral potential of the Lake Woods region, Northern Territory, Australia, <i>Australian Journal of Earth Sciences</i>, 66:3, 411-430, DOI: 10.1080/08120099.2018.1543208

Over 900 Australian mineral deposits, location and age data, combined with deposit classifications, have been used to assess temporal and spatial patterns of mineral deposits associated with convergent margins and allow assessment of the potential of poorly exposed or undercover mineral provinces and identification of prospective tracts within known mineral provinces. Here we present results of this analysis for the Eastern Goldfields Superterrane and the Tasman Element, which illustrate end-members of the spectrum of convergent margin metallogenic provinces. Combining our Australian synthesis with global data suggest that after ~3000 Ma these provinces are characterised by a reasonably consistent temporal pattern of deposit formation, termed the convergent margin metallogenic cycle (CMMC): volcanic-hosted massive sulfide – calc-alkalic porphyry copper – komatiite-associated nickel sulfide → orogenic gold → alkalic porphyry copper – granite-related rare metal (Sn, W and Mo) – pegmatite. Between ca 3000 Ma and ca 800 Ma, virtually all provinces are characterised by a single CMMC, but after ca 800 Ma, provinces mostly have multiple CMMCs. We interpret this change in metallogeny to reflect secular changes in tectonic style, with single-CMMC provinces associated with warm, shallow break-off subduction, and multiple-CMMC provinces associated with modern-style cold, deep break-off subduction. These temporal and spatial patterns can be used to infer potential for mineralisation outside well-established metallogenic tracts. <b>Citation:</b> Huston D. L., Doublier M. P., Eglington B., Pehrsson S., Mercier-Langevin P. & Piercey S., 2022. Convergent margin metallogenic cycling in the Eastern Goldfields Superterrane and Tasman Element. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/147037

High-purity quartz (HPQ) is the only naturally occurring and economically viable source for the production of silicon. Silicon is a critical mineral, and a key component in modern technologies such as semiconductors and photovoltaic cells. Critical minerals support the move towards a greater reliance on electrification, renewable energy sources and economic security. The global transition to net zero carbon emissions means there is a growing need for new discoveries of HPQ to supply the silicon production chain. HPQ deposits are identified in a multitude of geological settings, including pegmatites, hydrothermal veins, sedimentary accumulations and quartzite; however, deposits of sufficient volume and quality are rare. Quartz is abundant throughout Australia, but the exploration and discovery of HPQ occurrences are notably under-reported, making assessment of the HPQ potential in Australia extremely difficult. This paper presents a much-needed summary of the state of the HPQ industry, exploration and deposit styles in Australia. KEY POINTS: 1. High-purity quartz (HPQ) is a key material for the manufacture of photovoltaic cells, semiconductors and other high-technology applications. 2. HPQ can be recovered from a variety of different source rocks in a range of geological settings. 3. Currently, the HPQ industry in Australia is under-utilised for high-technology applications, and historical exploration and mining records are under-reported and opaque. 4. This review presents an outline of the characteristics, processing requirements and end uses of HPQ, and a summary of the operations, deposits, exploration targets and known occurrences of HPQ in Australia. <b>Citation:</b> Jennings, A., Senior, A., Guerin, K., Main, P., & Walsh, J. (2024). A review of high-purity quartz for silicon production in Australia. <i>Australian Journal of Earth Sciences</i>, 1–13. https://doi.org/10.1080/08120099.2024.2362296

<div>Maps showing the potential for iron oxide copper-gold (IOCG) mineral systems in Australia. Each of the mineral potential maps is a synthesis of four component layers (source of metals, fluids and ligands; energy sources and fluid flow drivers; fluid flow pathways and architecture; and ore depositional gradients). The model uses a hybrid data-driven and knowledge driven methodology to produce the final mineral potential map for the mineral system. An uncertainty map is provided in conjunction with the mineral potential maps that represents the availability of data coverage over Australia for the selected combination of input maps. Uncertainty values range between 0 and 1, with higher uncertainty values being located in areas where more input maps are missing data or have unknown values. The input maps and mineral deposits and occurrences used to generate the mineral potential map are provided along with an assessment criteria table which contains information on the map creation.</div>

Mineral deposits are the products of lithospheric-scale processes. Imaging the structure and composition of the lithosphere is therefore essential to better understand these systems, and to efficiently target mineral exploration. Seismic techniques have unique sensitivity to velocity variations in the lithosphere and mantle, and are therefore the primary means available for imaging these structures. Here, we present the first stage of Geoscience Australia's passive seismic imaging project (AusArray), developed in the Exploring for the Future program. This includes generation of compressional (P) and shear (S) body-wave tomographic imaging models. Our results, on a continental scale, are broadly consistent with a priori expectations for regional lithospheric structure and the results of previously published studies. However, we also demonstrate the ability to resolve detailed features of the Australian lithospheric mantle underneath the dense seismic deployments of AusArray. Contrasting P- and S-wave velocity trends within the Tennant Creek – Mount Isa region suggest that the lithospheric root may have undergone melt-related alteration. This complements other studies, which point towards high prospectivity for iron oxide–copper–gold mineralisation in the region. <b>Citation: </b>Haynes, M.W., Gorbatov, A., Hejrani, B., Hassan, R., Zhao, J., Zhang, F. and Reading, A.M., 2020. AusArray: imaging the lithospheric mantle using body-wave tomography. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

<div>Geoscience Australia’s Exploring for the Future (EFTF) program aims to enhance decision-making on Australia's mineral, energy, and groundwater resources by providing comprehensive geoscience data. Launched in 2016 with a $225m investment, the program has spawned various national projects, including the Australia's Resources Framework (ARF). The ARF focuses on a national perspective of Australia's surface and subsurface geology, supporting economic and social benefits, including transition to net-zero emissions.</div><div><br></div><div>One key sub-project within EFTF is the Geochemistry for Basin Prospectivity (G4BP) module. It explores Australian basins for basin-hosted base metal systems. The current focus (2020-2024) is on the Stuart Shelf region in South Australia, in collaboration with the Geological Survey of South Australia (GSSA) and CSIRO. The efforts aim to refine our understanding of sediment-hosted copper-cobalt-silver (Cu-Co-Ag) potential in this area.</div><div><br></div><div>This work has two primary objectives:</div><div><br></div><div>Geochemical fingerprinting and baseline data collection: Comprehensive data collection and reanalysis of existing samples aim to establish baseline geochemistry for stratigraphic units.</div><div>Mineral system components: Identification of potential metal sources, fluid sources, and trap rocks using a mineral systems approach.</div><div><br></div><div>This data release forms the second stage release of new geochemical data for the Stuart Shelf region; the first stage release was detailed in Champion et al. (2023b). There is also an earlier data release (Champion et al., 2023a) featuring reanalysis, by modern analytical methods, of legacy mineralised and/or altered Stuart Shelf and underlying basement samples held at Geoscience Australia.</div>

<div>The footprint of a mineral system is potentially detectable at a range of scales and lithospheric depths, reflecting the size and distribution of its components. Magnetotellurics is one of a few techniques that can provide multiscale datasets to understand mineral systems. The Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) is a collaborative national survey that acquires long-period magnetotelluric data on a half-degree grid spacing (about 55 km) across Australia. This project aims to map the electrical conductivity/resistivity structure in the crust and mantle beneath the Australian continent. We have used AusLAMP as a first-order reconnaissance survey to resolve large-scale lithospheric architecture for mapping areas of mineral potential in Australia. AusLAMP results show a remarkable connection between conductive anomalies and giant mineral deposits in known highly endowed mineral provinces. Similar conductive features are mapped in greenfield areas where mineralisation has not been previously recognised. In these areas we can then undertake higher-resolution infill magnetotelluric surveys to refine the geometry of major structures, and to investigate if deep conductive structures are connected to the near surface by crustal-scale fluid-flow pathways.</div><div> We summarise the results from a 3D resistivity model derived from AusLAMP data in Northern Australia. This model reveals a broad conductivity anomaly in the lower crust and upper mantle that extends beneath an undercover exploration frontier between the producing Tennant Creek region and the prospective Murphy Province. This anomaly potentially represents a fertile source region for mineral systems. A subsequent higher-resolution infill magnetotelluric survey revealed two prominent conductors within the crust whose combined responses produced the lithospheric-scale conductivity anomaly mapped in the AusLAMP model. Integration of the conductivity structure with deep seismic reflection data revealed a favourable crustal architecture linking the lower, fertile source regions with potential depositional sites in the upper crust. Integration with other geophysical and geochronological datasets suggests high prospectivity for major mineral deposits in the vicinity of major faults.</div><div> This study demonstrates that the integration of geophysical data from multiscale surveys is an effective approach to scale reduction during mineral exploration in covered terranes.</div> This Abstract was submitted to and presented at the 6th International Archean Symposium Target 2023, 28 July (https://6ias.org/target2023/)

The Exploring for the Future program Showcase 2024 was held on 13-16 August 2024. Day 4 - 16th August talks included: <b>Session 1 – Deep Dives into the Delamerian</b> <a href="https://youtu.be/09knAwPnD7s?si=acdu6pQgIj7DNlnj">Scaffold to success: An overview of the Delamerian Orogen, and its crustal and lithospheric architecture</a> - Chris Lewis <a href="https://youtu.be/5GQC5f5IkWc?si=rLPqxoZFkxGAEPEf">Only time will tell: Crustal development of the Delamerian Orogen in space and time</a> - David Mole <a href="https://youtu.be/PhdIYE49eqU?si=d7acyv5rbTW_wTiO">Is it a big deal? New mineral potential insights of the Delamerian Orogen</a> - Dr Yanbo Cheng <b>Session 2 – Deep dives into Birrindudu, West Musgrave and South Nicholson–Georgina regions</b> <a href="https://youtu.be/DEbkcgqwLE8?si=sBKGaMTq_mheURib">Northwest Northern Territory Seismic Survey: Resource studies and results</a> - Paul Henson <a href="https://youtu.be/k9vwBa1fM9E?si=VOG19nBC1DAk-jGH">Tracing Ancient Rivers: A hydrogeological investigation of the West Musgrave Region</a> - Joshua Lester <a href="https://youtu.be/Du1JANovz8M?si=1XEOF87gxhSP9UF3">Water's journey: Understanding groundwater dynamics in the South Nicholson and Georgina basins, NT and QLD </a>- Dr Prachi Dixon-Jain <b>Session 3 – Groundwater systems of the Curnamona and upper Darling-Baaka River</b> <a href="https://youtu.be/nU8dpekmEHQ?si=WygIzefKNzsU4gUA">Groundwater systems of the upper Darling-Baaka floodplain: An integrated assessment</a> - Dr Sarah Buckerfield <a href="https://youtu.be/AKOhuDEPxIA?si=ebradAT6EBwHhPQ_">Potential for a Managed Aquifer Recharge Scheme in the upper Darling-Baaka floodplain: Wilcannia region</a> - Dr Kok Piang Tan <a href="https://youtu.be/epUdD8ax2FQ?si=_aMO_e_ZDZESgLOR">Aquifer alchemy: Decoding mineral clues in the Curnamona region</a> - Ivan Schroder Exploring for the Future: Final reflection – Karol Czarnota Resourcing Australia’s Prosperity – Andrew Heap View or download the <a href="https://dx.doi.org/10.26186/149800">Exploring for the Future - An overview of Australia’s transformational geoscience program</a> publication. View or download the <a href="https://dx.doi.org/10.26186/149743">Exploring for the Future - Australia's transformational geoscience program</a> publication. You can access full session and Q&A recordings from YouTube here: 2024 Showcase Day 4 - Session 1 - <a href="https://www.youtube.com/watch?v=4nuIQsl71cY">Deep Dives into the Delamerian</a> 2024 Showcase Day 4 - Session 2 - <a href="https://www.youtube.com/watch?v=9N3dIZRAcHk">Deep dives into Birrindudu, West Musgrave and South Nicholson–Georgina regions</a> 2024 Showcase Day 4 - Session 3 - <a href="https://www.youtube.com/watch?v=_ddvLAnUdOI">Groundwater systems of the Curnamona and upper Darling-Baaka River</a>

<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>

<div>Geoscience Australia’s Exploring for the Future program provides precompetitive information to inform decision-making by government, community and industry on the sustainable development of Australia's mineral, energy and groundwater resources. By gathering, analysing and interpreting new and existing precompetitive geoscience data and knowledge, we are building a national picture of Australia’s geology and resource potential. This leads to a strong economy, resilient society and sustainable environment for the benefit of all Australians. This includes supporting Australia’s transition to net zero emissions, strong, sustainable resources and agriculture sectors, and economic opportunities and social benefits for Australia’s regional and remote communities. The Exploring for the Future program, which commenced in 2016, is an eight year, $225m investment by the Australian Government.</div><div><br></div><div>As part of Exploring for the Future (EFTF) program with contributions from the Geological Survey of Queensland, long-period magnetotelluric (MT) data for the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) were collected using Geoscience Australia's LEMI-424 instruments on a half-degree grid across northern and western Queensland from April 2021 to November 2022. This survey aims to map the electrical resistivity structures in the region. The processed data and 3D resistivity model have been released (https://dx.doi.org/10.26186/148633).&nbsp;</div><div><br></div><div>This data release contains site locations and acquired time series data at each site in two formats:</div><div>1. MTH5, a hierarchical data format. The open-source MTH5 Python package (https://github.com/kujaku11/mth5) was used to convert the recorded LEMI data into MTH5 format.</div><div>2. Text file (*.TXT). This is the original format recorded by the LEMI-424 data logger.</div><div><br></div><div>We acknowledge the traditional landowners, private landholders and national park authorities within the survey region, without whose cooperation these data could not have been collected.</div><div><br></div><div><strong>Data is available on request from clientservices@ga.gov.au - Quote eCat# 148978</strong></div><div><br></div>