<div><strong>Output Type:</strong> Exploring for the Future Extended Abstract</div><div><br></div><div><strong>Short Abstract: </strong>An advanced understanding of regional-scale metallogenic characteristics and ore-formation controls is fundamental for mineral discovery, particularly in underexplored covered terranes, such as the Delamerian Orogen of southeastern Australia. The Delamerian Orogen is defined as the spatial extent of rocks first deformed by the Delamerian Orogeny, though the Orogen was also affected by younger geodynamic events. Petrology of the mineralised host rocks from over 20 mineral prospects and deposits has led to the recognition of four types of mineral systems related to the geodynamic history of the Delamerian Orogen on mainland Australia, including (1) porphyry-epithermal; (2) volcanic-hosted massive sulphide (VHMS); (3) orogenic gold; and (4) mafic-ultramafic magmatic Cu-Ni-PGE systems. Several other prospects are yet to be classified due to insufficient data, although there is strong evidence to suggest that these are magmatic-hydrothermal in origin. Direct dating of hydrothermal alteration and mineralisation at key mineral deposits and prospects (using U-Pb in titanite and apatite, and Sm-Nd in fluorite) identified four major metallogenic events in the Delamerian Orogen margin. The middle to late Cambrian (505–494 Ma) mineral systems, throughout the eastern margin of the Delamerian Orogen, are potentially the most significant. However, our new dating indicates other metallogenic events at 590–580 Ma, 480–460 Ma, and 412–399 Ma. Analysis of data related to mineral systems fertility reveals crustal controls on the location and type of mineralisation in the Delamerian Orogen. Integration of Hf and O isotopes in zircon, and S isotopes in sulphide minerals indicates that the geology of the Orogen may host multiple opportunities for mineral system development. An indicative map of ca.600–400 Ma mineral system potential was developed by integrating this new data, together with other geological, geochemical and geophysical datasets within the geodynamic context of the Delamerian Orogen. Importantly, this study demonstrates the metallogenic characteristics of multiple types and episodes of mineral system development, and the geological processes that have controlled their formation to aid exploration.</div><div><br></div><div><strong>Citation: </strong>Cheng, Y., Gilmore, P., Lewis, C., Roach, I., Clark, A., Mole, D., Pitt, L., Doublier, M., Sanchez, G., Schofield, A., O'Rourke, A., Budd, A., Huston, D., Czarnota, K., Meffre, S., Feig, S., Maas, R., Gilbert, S., Cairns, C., Cayley, R., Wise, T., Wade, C., Werner, M., Folkes, C. &amp; Hughes, K., 2024. Mineral systems and metallogeny of the Delamerian Orogen margin. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts. Geoscience Australia, Canberra. https://doi.org/10.26186/149657</div><div><br></div>

<div>As part of the Australia's Resources Framework Project, in the Exploring for the Future Program, Geoscience Australia and CSIRO have undertaken a magnetic source depth study across four areas. These are: 1) the western part of Tasmania that is the southernmost extension of the Darling-Curnamona-Delamerian (DCD) project area; 2) northeastern Queensland; 3) the Officer Basin area of western South Australia and southeastern West Australia; and 4) the 'Eastern Resources Corridor' (ERC) covering eastern South Australia, southwest Queensland, western New South Wales and western Victoria. This study has produced 2005 magnetic estimates of depth to the top of magnetization. The solutions are derived by a consistent methodology (targeted magnetic inversion modelling, or TMIM; also known as ‘sweet-spot’ modelling). </div><div><br></div><div>The magnetic depth estimates produced as part of this study provide depth constraints in data-poor areas. They help to construct a better understanding of the 3D geometry of the Australian continent, and aid cover thickness modelling activities. </div><div><br></div><div>A supplementary interpretation data release is also available through Geoscience Australia's enterprise catalogue (ecat) at https://pid.geoscience.gov.au/dataset/ga/149499.</div><div><br></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. This work contributes to building a better understanding of the Australian continent, whilst giving the Australian public the tools they need to help them make informed decisions in their areas of interest.</div>

<div>The Darling-Curnamona-Delamerian (DCD) project focused on the covered portion of the Delamerian orogen, situated in the south-eastern mainland states of Australia.&nbsp;The aims of the project were to develop a greater understanding of the geodynamic history of the Delamerian Orogen, characterise known magmatic-hydrothermal mineral systems, and assess mineral potential for a suite of minerals including copper (Cu), gold (Au), and nickel (Ni), and critical minerals like platinum-group elements (PGEs) and rare-earth elements (REEs). </div><div>Here, we collate whole rock geochemistry data from new and legacy samples of mafic to intermediate magmatic rocks of the Loch Lilly-Kars Belt in order to determine the likely source of these magmas and constrain the prevailing tectonic setting during their emplacement. We apply multi-elemental diagrams and various elemental discrimination diagrams to characterise various groups of magmatic rocks in these belts, taking into account their geographic affinity and new geochronological data (e.g. Mole et al., 2023; Mole et al., 2024). The geochemical characteristics of these groups and the implications for the tectonic setting into which they were emplaced are discussed. Comparisons are made with potentially similar magmatic rocks of the&nbsp;Koonenberry Belt and Grampians-Stavely Zone. Results from this study have significant implications for the tectonic setting in which the Loch Lilly-Kars Belt developed, and hence also the mineral potential of the Belt. </div><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 a low emissions economy, strong 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. The Darling-Curnamona-Delamerian (DCD) 2D reflection seismic survey was acquired during May to August 2022 in the Delamerian Orogen, the Murray-Darling basin, the Curnamona Province, and the upper Darling River floodplain regions in South Australia, Victoria and New South Wales. This project is a collaboration between Geoscience Australia (GA), the Geological Survey of South Australia (GSSA), the Geological Survey of Victoria (GSV) and the Geological Survey of New South Wales (GSNSW) and was funded by the Australian Government’s Exploring for the Future (EFTF) program. The overall objective of the EFTF Darling-Curnamona-Delamerian project is to improve the understanding of mineral and groundwater resources of the Curnamona Province and Delamerian Orogen and overlying basin systems through acquisition and interpretation of new pre-competitive geoscience data sets. The total length of acquisition was 1256 km distributed over five deep crustal 2D reflection seismic lines 22GA-DL1 (446 km), 22GA-DL2 (249 km), 22GA-CD1 (287 km), 22GA-CD2 (178 km), 22GA-CD3 (39.5 km) to image deep crustal structures, and a high-resolution 2D reflection seismic line 22GA-UDF (56 km) to explore groundwater resources. The DL lines provide coverage of fundamental geophysical data over the Flinders Range, the Delamerian Province and the Murray-Darling basin region in eastern South Australia and Victoria. The CD lines extend through the Curnamona Province and into the Darling Basin. The UDF line will assist with refining the hydrogeological model, understanding groundwater dynamics, and locating areas better suited to groundwater bores for better quality groundwater in the upper Darling River floodplain area. The data processing was performed by a contractor under the supervision of Geoscience Australia. The five deep crustal lines (22GA-DL1,DL2,CD1,CD2,CD3) were processed with record lengths of 20 and 8 seconds, while the shallow high-resolution line (22GA-UDF) was processed at a 4 second length. This processing yielded DMO Stack, Post-Stack Time Migration, and Pre-Stack Time Migration products. <strong>Raw shot gathers and processed gathers for this survey are available on request from clientservices@ga.gov.au - Quote eCat# 147423</strong>