The Exploring for the Future program Showcase 2022 was held on 8-10 August 2022. Day 2 (9th August) included talks on two themes moderated by Marina Costelloe. Data and toolbox theme: - Data acquisition progress - Dr Laura Gow - Quantitative tool development: HiQGA.jl and HiPerSeis - Dr Anandaroop Ray - Data delivery advances: Underpinned by careful data curation - Mark Webster Geology theme: - Mapping Australia's geology: From the surface down to great depths - Dr Marie-Aude Bonnardot - Towards a national understanding of Groundwater - Dr Hashim Carey - Uncovering buried frontiers: Tennant Creek to Mount Isa - Anthony Schofield and Dr Chris Carson - Lithospheric characterisation: Mapping the depths of the Australian tectonic plate - Dr Marcus Haynes You can access the recording of the talks from YouTube here: Showcase Day 2 – Part 1 https://youtu.be/US6C-xzMsnI Showcase Day 2 – Part 2 https://youtu.be/ILRLXbQNnic

The Exploring for the Future program Showcase 2022 was held online on 8-10 August 2022. Day 3 (10th August) included talks on two themes moderated by David Robinson. Minerals, energy and groundwater systems theme: - Upper Darling Floodplain - Dr Sarah Buckerfield - Geoscience insights from Energy Resources - Lidena Carr - Mineral systems insights: New concepts from old data - Dr David Huston Resource potential theme: - Mineral Potential: Narrowing the exploration search space - Dr Arianne Ford - CO2-Enhanced oil recovery: Application to residual oil zones - Dr Aleks Kalinowski - Hydrogen and green steel - Dr Andrew Feitz You can access the recording of the talks from YouTube here: Day 3 part 1 https://youtu.be/cdzn3JNReOs Day 3 part 2 https://youtu.be/DjghAig51Ao

The Exploring for the Future program Showcase 2022 was held on 8-10 August 2022. Day 1 (8th August) included a talk on: - Exploring for the Future - The value of precompetitive geoscience - Dr Andrew Heap Showcase Day 1 https://youtu.be/M9jC_TyovCc

This service provides access to airborne electromagnetics (AEM) derived conductivity grids in the Upper Darling Floodplain region. The grids represent 30 depth intervals from modelling of AEM data acquired in the Upper Darling Floodplain, New South Wales, Airborne Electromagnetic Survey (https://dx.doi.org/10.26186/147267), an Exploring for the Future (EFTF) project jointly funded by Geoscience Australia and New South Wales Department of Planning and Environment (NSW DPE). The AEM conductivity model delineates important subsurface features for assessing the groundwater system including lithological boundaries, palaeovalleys and hydrostatigraphy.

All commercially produced hydrogen worldwide is presently stored in salt caverns. In eastern Australia, the only known thick salt accumulations are found in the Boree Salt of the Adavale Basin in central Queensland. Although the number of wells penetrating the basin is limited, salt intervals up to 555 m thick have been encountered. The Boree Salt consists predominantly of halite and is considered to be suitable for hydrogen storage. Using well data and historical 2D seismic interpretations, we have developed a 3D model of the Adavale Basin, particularly focussing on the thicker sections of the Boree Salt. Most of the salt appears to be present at depths greater than 2000 m, but shallower sections are found in the main salt body adjacent to the Warrego Fault and to the south at the Dartmouth Dome. The preliminary 3D model developed for this study has identified three main salt bodies that may be suitable for salt cavern construction and hydrogen storage. These are the only known large salt bodies in eastern Australia and therefore represent potentially strategic assets for underground hydrogen storage. There are still many unknowns, with further work and data acquisition required to fully assess the suitability of these salt bodies for hydrogen storage. Recommendations for future work are provided. <b>Citation:</b> Paterson R., Feitz A. J., Wang L., Rees S. & Keetley J., 2022. From A preliminary 3D model of the Boree Salt in the Adavale Basin, Queensland. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/146935

To unlock the potential of one of the largest underexplored onshore areas in Australia, the Exploring for the Future Officer-Musgrave project is delivering a wide array of publicly available new analyses and data. The collection of new AEM data, as well as the reprocessing of existing industry acquired AEM data is expected to improve the understanding of groundwater systems in the Officer-Musgrave region. New regional scale data acquisition and analysis, including stratigraphic, petrophysical and geomechanical studies from existing wells, focus on advancing understanding of petroleum systems elements and assist the exploration and evaluation of conventional and unconventional petroleum resources. Here we provide an overview of available new datasets and insights into the stratigraphy of the Officer Basin. Further analysis is underway including well log digitisation, fluid inclusion analysis and a petrographic report on Officer Basin wells. This work is expected to further improve geological knowledge and reduce the energy exploration risk of the Officer Basin, a key focus of this program. <b>Citation: </b>Carr L. K., Henson P., Wang L., Bailey A., Fomin T., Boreham C., Edwards D., Southby C., Symington N., Smith M., Halas L. & Jones T, 2022. Exploring for the Future in the Officer Musgrave region. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/146988

Magnetotellurics is one of few techniques those can provide multiple-scale datasets to understand the larger mineral system. We have used long-period data from the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) as first-order reconnaissance survey to resolve large-scale lithospheric architectures for mapping areas of mineral potential in northern Australia. The 3D resistivity model reveals a broad conductivity anomaly extending from the Tennant Region to the Murphy Province, representing a potential fertile source region for mineral systems. We then undertook a higher-resolution infill magnetotellurics survey to refine the geometry of major structures, and to investigate if the deep structure is connected to the near surface by crustal-scale fluid pathways. The resistivity models reveal two prominent conductors in the resistive host whose combined responses result in the lithospheric-scale conductivity anomaly mapped in the AusLAMP model. The resistivity contrasts coincide with major structures preliminarily interpreted from seismic reflection and potential field data. Most importantly, the conductive structures extend from the lower crust to the near surface at where the major faults are located. This observation strongly suggests that these major faults are deep-penetrating structures that potentially acted as pathways for transporting metalliferous fluids to the upper crust where they could form mineral deposits. This result indicates high mineral prospectivity for iron oxide copper–gold deposits in the vicinity of these major faults. We then used high-frequency data to estimate cover thickness to assist with drill targeting for the stratigraphic drilling program which, in turn, will test the models and improve our understanding of basement geology, cover sequences and mineral potential. This study demonstrates that integration of geophysical data from multiscale surveys is an effective approach to scale reduction during mineral exploration in covered terranes. This Abstract was submitted/presented to the 2021 Australasian Exploration Geoscience Conference 13 - 17 September https://2021.aegc.com.au/.

This report presents key results from the Howard East project conducted as part of Exploring for the Future (EFTF), an Australian Government funded geoscience data and information acquisition program. The four-year (2016–20) program focused on better understanding the potential mineral, energy and groundwater resources in northern Australia. Groundwater is an essential part of Darwin’s water supply and is sourced from the Koolpinyah Dolostone Aquifer (KDA) at the Howard East Borefield (HEB) and McMinns Borefield, which are ~25 km to 30 km southeast of Darwin. Previous work suggests that electrical conductivity anomalies observed in airborne electromagnetic (AEM) data within 5 km of HEB may be caused by saline groundwater within the KDA that is separated from HEB by dykes and other geological features that effectively compartmentalise the aquifer (Fell-Smith & Sumner, 2011; Tan et al., 2012). Nevertheless, concerns have grown that increased groundwater use may result in migration of saline groundwater toward HEB, which could compromise the groundwater resource. We collected groundwater chemistry including isotopes, time-series groundwater salinity, AEM, and induction and gamma data to better understand the complexities of the KDA. We show that groundwater in the KDA typically has a fresh Mg-Ca-HCO3 type composition, as is expected for a dolomitic aquifer. Highly saline Na-Cl type groundwater with a composition similar to seawater exists at some locations as well as groundwater with a mixed composition. These findings confirm previous interpretations for the area (e.g. Fell-Smith & Sumner, 2011). We sampled saline groundwater on the opposite side of two dolerite dykes to HEB to its northeast. Age dating results for this sample cannot be used to determine whether this saline groundwater represents relict seawater or whether groundwater at this site is in hydraulic connection with the modern ocean. Our groundwater chemistry results also show that saline intrusion is occurring northwest of HEB. AEM data were collected to better characterise geological and hydrogeological features in the area. Estimates of bulk conductivity of the subsurface were derived by inverting AEM data using both deterministic and stochastic methods. Using these AEM inversions and other hydrogeological information, we characterised high-conductivity anomalies within 5 km of HEB and the upper surface of unweathered dolerite in the two dykes northeast of HEB. We interpreted conductivity anomalies as pyritic shales, although drilling is required to investigate the salinity of groundwater in the KDA in this area. Where we were able to resolve the upper surface of unweathered material in the two dykes using the AEM, we found that it commonly occurs below sea level. Characterising the geometry of these dykes will aid in assessing their role in aquifer compartmentalisation. Our findings contribute to building a robust conceptual understanding of the KDA and will guide future investigations into the groundwater system. A number of other products exist for the EFTF Howard East project. The findings of this report are integrated with hydrodynamic analyses undertaken by Woltmann (in prep.) and reported in Haiblen et al. (2020). Hydrochemistry data presented here are contained in McGrath-Cohen et al. (2020), water level and salinity monitoring data can be found in Turner et al. (2020), AEM data are in Ray et al. (2020b), and induction and gamma data are in Tan et al. (2020).

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

With the increasing need to extend mineral exploration undercover, new approaches are required to better constrain concealed geology, thereby reducing exploration risk and search space. Hydrogeochemistry is an under-utilised tool that can identify subsurface geology and buried mineral system components, while also providing valuable insights into environmental baselines, energy systems and groundwater resources. With this aim, 238 water bores spanning seven geological provinces in the Northern Territory and Queensland were sampled and analysed for major cations and anions, trace elements, stable and radiogenic isotopes, organic species, and dissolved gases. Here, we demonstrate the utility of this dataset for identifying carbonate-rich aquifers and mineral system components therein. First, we use trends in major element ratios (Ca+Mg)/Cl– and SiO2/HCO–3, then strontium isotope ratios (87Sr/86Sr), to define subpopulations that reflect both spatial and compositional differences. We then apply mafic-to-felsic trace element ratios (V/Cs and Cu/Rb) to reveal elevated base metal concentrations near Lake Woods caused by water–rock interaction with dolerite intrusions. Correlated Sr concentrations between groundwater and surface sediments suggest that the geochemical evolution of these mediums in carbonate-dominated terrains is coupled. Our work develops an approach to guide mineral exploration undercover via the characterisation and differentiation of groundwaters from different aquifers, resulting in improved identification of geochemical anomalies. <b>Citation:</b> Schroder, I., de Caritat, P. and Wallace, L., 2020. The Northern Australia Hydrogeochemical Survey: aquifer lithologies, local backgrounds and undercover processes. 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.