The Exploring for the Future program Showcase 2023 was held on 15-17 August 2023. Day 3 - 17th August talks included: Geological Processes and Resources Session Large scale hydrogen storage: The role of salt caverns in Australia’s transition to net zero – Dr Andrew Feitz Basin-Hosted Base Metal Deposits – Dr Evgeniy Bastrakov Upper Darling Floodplain: Groundwater dependent ecosystem assessment – Dr Sarah Buckerfield Atlas of Australian Mine Waste: Waste not, want not – Jane Thorne Resource Potential Theme National-scale mineral potential assessments: supporting mineral exploration in the transition to net zero – Dr Arianne Ford Australia’s Onshore Basin Inventories: Energy – Tehani Palu Prioritising regional groundwater assessments using the national hydrogeological inventory – Dr Steven Lewis Assessing the energy resources potential in underexplored regions – Dr Barry Bradshaw You can access the recording of the talks from YouTube here: <a href="https://youtu.be/pc0a7ArOtN4">2023 Showcase Day 3 - Part 1</a> <a href="https://youtu.be/vpjoVYIjteA">2023 Showcase Day 3 - Part 2</a>

The discovery of strategically located salt structures, which meet the requirements for geological storage of hydrogen, is crucial to meeting Australia’s ambitions to become a major hydrogen producer, user and exporter. The use of the AusAEM airborne electromagnetic (AEM) survey’s conductivity sections, integrated with multidisciplinary geoscientific datasets, provides an excellent tool for investigating the near-surface effects of salt-related structures, and contributes to assessment of their potential for underground geological hydrogen storage. Currently known salt in the Canning Basin includes the Mallowa and Minjoo salt units. The Mallowa Salt is 600-800 m thick over an area of 150 × 200 km, where it lies within the depth range prospective for hydrogen storage (500-1800 m below surface), whereas the underlying Minjoo Salt is generally less than 100 m thick within its much smaller prospective depth zone. The modelled AEM sections penetrate to ~500 m from the surface, however, the salt rarely reaches this level. We therefore investigate the shallow stratigraphy of the AEM sections for evidence of the presence of underlying salt or for the influence of salt movement evident by disruption of near-surface electrically conductive horizons. These horizons occur in several stratigraphic units, mainly of Carboniferous to Cretaceous age. Only a few examples of localised folding/faulting have been noted in the shallow conductive stratigraphy that have potentially formed above isolated salt domes. Distinct zones of disruption within the shallow conductive stratigraphy generally occur along the margins of the present-day salt depocentre, resulting from dissolution and movement of salt during several stages. This study demonstrates the potential AEM has to assist in mapping salt-related structures, with implications for geological storage of hydrogen. In addition, this study produces a regional near-surface multilayered chronostratigraphic interpretation, which contributes to constructing a 3D national geological architecture, in support of environmental management, hazard mapping and resource exploration. <b>Citation: </b>Connors K. A., Wong S. C. T., Vilhena J. F. M., Rees S. W. & Feitz A. J., 2022. Canning Basin AusAEM interpretation: multilayered chronostratigraphic mapping and investigating hydrogen storage potential. In: Czarnota, K (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/146376

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

This data package provides seismic interpretations that have been generated in support of the energy resource assessments under the Australia’s Future Energy Resources (AFER) project. Explanatory notes are also included. The AFER project is part of Geoscience Australia’s Exploring for the Future (EFTF) Program—an eight year, $225 million Australian Government funded geoscience data and precompetitive information acquisition program 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, Geoscience Australia is building a national picture of Australia’s geology and resource potential. This will help support a strong economy, resilient society and sustainable environment for the benefit of all Australians. The EFTF program is supporting Australia’s transition to a low emissions economy, industry and agriculture sectors, as well as economic opportunities and social benefits for Australia’s regional and remote communities. Further details are available at http://www.ga.gov.au/eftf. The seismic interpretations build on the recently published interpretations by Szczepaniak et al. (2023) by providing updated interpretations in the AFER Project area for the Top Cadna-owie (CC10) and Top Pre-Permian (ZU) horizons, as well as interpretations for 13 other horizons that define the tops of play intervals being assessed for their energy resource potential (Figure 1). Seismic interpretations for the AFER Project are constrained by play interval tops picked on well logs that have been tied to the seismic profiles using time-depth data from well completion reports. The Pedirka and Western Eromanga basins are underexplored and contain relatively sparse seismic and petroleum well data. The AFER Project has interpreted play interval tops in 41 wells, 12 seismic horizons (Top Cadna-owie and underlying horizons) on 238 seismic lines (9,340 line kilometres), and all 15 horizons on 77 recently reprocessed seismic lines (3,370 line kilometres; Figure 2). Note that it has only been possible to interpret the Top Mackunda-Winton, Top Toolebuc-Allaru and Top Wallumbilla horizons on the reprocessed seismic lines as these are the only data that provide sufficient resolution in the shallow stratigraphic section to confidently interpret seismic horizons above the Top Cadna-owie seismic marker. The seismic interpretations are provided as point data files for 15 horizons, and have been used to constrain the zero edges for gross-depositional environment maps in Bradshaw et al. (2023) and to produce depth-structure and isochore maps for each of the 14 play intervals in Iwanec et al. (2023). The data package includes the following datasets: 1) Seismic interpretation point file data in two-way-time for up to 15 horizons using newly reprocessed seismic data and a selection of publicly available seismic lines (Appendix A). 2) Geographical layers for the seismic lines used to interpret the top Cadna-owie and underlying horizons (Cadnaowie_to_TopPrePermian_Interpretation.shp), and the set of reprocessed lines used to interpret all 15 seismic horizons (All_Horizons_Interpretation.shp; Appendix B). These seismic interpretations are being used to support the AFER Project’s play-based energy resource assessments in the Pedirka and Western Eromanga basins.

<div>The Adavale Basin is located approximately 850 km west-northwest of Brisbane and southwest of Longreach in south-central Queensland. The basin system covers approximately 100,000 km2 and represents an Early to Late Devonian (Pragian to Famennian) depositional episode, which was terminated in the Famennian by widespread contractional deformation, regional uplift and erosion. </div><div>Burial and thermal history models were constructed for nine wells using existing open file data to assess the lateral variation in maturity and temperature for potential source rocks in the Adavale Basin, and to provide an estimate of the hydrocarbon generation potential in the region.</div>

<div>Geoscience Australia’s Onshore Basin Inventories program provides a whole-of-basin inventory of geology, energy systems, exploration status and data coverage of onshore Australian basins. Volume 1 of the inventory covers the McArthur, South Nicholson, Georgina, Wiso, Amadeus, Warburton, Cooper and Galilee basins and Volume 2 expands this list to include the Officer, Perth and onshore Canning basins. These reports provide a single point of reference and create a standardised national inventory of onshore basins. In addition to summarising the current state of knowledge within each basin, the onshore basin inventory identifies critical science questions and key exploration uncertainties that may help inform future work program planning and aid in decision making for both government and industry organisations. Under Geoscience Australia’s Exploring for the Future (EFTF) program, six new onshore basin inventory reports will be delivered. </div><div>&nbsp;</div><div>These reports will be supported by selected value-add products that aim to address identified data gaps and evolve regional understanding of basin evolution and prospectivity. Petroleum system modelling is being undertaken in selected basins to highlight the hydrocarbon potential in underexplored provinces, and seismic reprocessing and regional geochemical studies are underway to increase the impact of existing datasets. The inventories are supported by the ongoing development of the nationwide source rock and fluids atlas, accessed through Geoscience Australia’s Exploring for the Future Data Discovery Portal, which continues to improve the veracity of petroleum system modelling in Australian onshore basins.</div><div>&nbsp;</div><div>In summarising avenues for further work, the Onshore Basin Inventories program has provided scientific and strategic direction for pre-competitive data acquisition under the EFTF work program. Here, we provide an overview of the current status of the Onshore Basin Inventories, with emphasis on its utility in shaping EFTF data acquisition and analysis, as well as new gap-filling data acquisition</div> This Abstract was submitted/presented at the 2023 Australasian Exploration Geoscience Conference (AEGC) 13-18 March (https://2023.aegc.com.au/)

Internationally, the number of carbon capture and storage (CCS) projects has been increasing with more than 61 new CCS facilities added to operations around the globe in 2022, including six projects in Australia (GCCSI, 2022). The extraction of reservoir fluid will be an essential component of the CCS workflow for some of projects in order to manage reservoir pressure variations and optimise the subsurface storage space. While we refer to reservoir fluid as brine throughout this paper for simplicity, reservoir fluids can range from brackish to more saline (briny) water. Brine management requires early planning, as it has implications for the project design and cost, and can even unlock new geological storage space in optimal locations. Beneficial use and disposal options for brine produced as a result of carbon dioxide (CO2) storage has been considered at a regional or national scale around the world, but not yet in Australia. For example, it may be possible to harvest energy, water, and mineral resources from extracted brine. Here, we consider how experiences in brine management across other Australian industries can be transferred to domestic CCS projects.

Carbon capture and storage (CCS) is a central component of many proposed pathways to reach net zero CO2 emissions by 2050. Even under conservative estimates, successful deployment of CCS projects at scale will require a substantial investment in the selection and development of new sequestration sites. While several studies have considered the potential costs associated with individual sequestration projects, and others have evaluated the costs of capture and sequestration in a generic manner, few have examined how regional differences in transport distances and reservoir properties may affect the overall costs of sequestration projects. In this abstract, we outline a new model to assess the costs associated with new carbon sequestration projects. The model evaluates the cost of CCS projects accounting for regional variations in transport distance and cost and well the storage properties of individual reservoirs. We present preliminary results from the modelling tool, highlighting potential opportunities for new CCS projects.

Underground hydrogen storage (UHS) in halite caverns will become an essential technology to supplement energy supply networks. This study examines the feasibility of UHS in the offshore Polda Basin by integrating previous seismic interpretation, well data and regional geology information. The Mercury structure in the central – east Polda Basin has extensive halite accumulations (both vertically and laterally) and has been identified as an area with high UHS potential. The net halite thickness is more than 1000 m, while the total potential area is about 217 km². Well data from the Mercury 1 well show a low thermal gradient (1.7–2.1 °C/100m) and overburden pressure gradient of approximately 18 ppg, providing effective gas operation pressure for UHS. To illustrate the feasibility of UHS, a conceptual design of a halite cavern is provided for a depth range of 1650–2000 m. Caverns with diameters of 60 m and 100 m are estimated to have storage capacities of approximately 240 GWh and 665 GWh, respectively. Multiple halite caverns could be constructed within the extensive Mercury halite accumulation. Further investigation into the potential for salt accumulations in the onshore Polda Basin is recommended. <b>Citation: </b>Feitz A. J., Wang L., Rees S. & Carr L., 2022. Feasibility of underground hydrogen storage in a salt cavern in the offshore Polda Basin. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/146501

CO₂ enhanced oil recovery (CO₂-EOR) is a proven technology that can extend the life of oil fields, permanently store CO₂, and improve the recovery of oil and condensate over time. Although CO₂-EOR has been used successfully for decades, particularly in the United States, it has not gained traction in Australia to date. In this study, we assemble and evaluate data relevant to CO₂-EOR for Australia’s key oil and condensate producing basins, and develop a national-scale, integrated basin ranking that shows which regions have the best overall conditions for CO₂-EOR. The primary goals of our study are to determine whether Australia’s major hydrocarbon provinces exhibit suitable geological and oil characteristics for successful CO₂-EOR activities and to rank the potential of these basins for CO₂-EOR. Each basin is assessed based on the key parameters that contribute to a successful CO₂-EOR prospect: oil properties (API gravity), pressure, temperature, reservoir properties (porosity, permeability, heterogeneity), availability of CO₂ for EOR operations, and infrastructure to support EOR operations. The top three ranked basins are the onshore Bowen-Surat, Cooper-Eromanga and offshore Gippsland Basins, which are all in relatively close proximity to the large east coast energy/oil markets. A significant factor that differentiates these three basins from the others considered in this study is their relatively good access to CO₂ and well-developed infrastructure. The next three most suitable basins are located offshore on the Northwest Shelf (Browse, Carnarvon, and Bonaparte Basins). While these three basins have mostly favourable oil properties and reservoir conditions, the sparse CO₂ sources and large distances involved lead to lower scores overall. The Canning and Amadeus Basins rank the lowest among the basins assessed, being relatively immature and remote hydrocarbon provinces, and lacking the required volumes of CO₂ or infrastructure to economically implement CO₂-EOR. In addition to ranking the basins for successful implementation of CO₂-EOR, we also provide some quantification of the potential recoverable oil in the various basins. These estimates used the oil and condensate reserve numbers that are available from national databases combined with application of internationally observed tertiary recovery factors. Additionally, we estimate the potential mass of CO₂ that would be required to produce these potential recoverable oil and condensate resources. In the large oil- and condensate-bearing basins, such as the Carnarvon and Gippsland Basins, some scenarios require over a billion tonnes of CO₂ to unlock the full residual resource, which points to CO₂ being the limiting factor for full-scale CO₂-EOR development. Even taking a conservative view of the available resources and potential extent of CO₂-EOR implementation, sourcing sufficient amounts of CO₂ for large-scale deployment of the technology presents a significant challenge. <b>Citation:</b> Tenthorey, E., Kalinowski, A., Wintle, E., Bagheri, M., Easton, L., Mathews, E., McKenna, J., Taggart, I. 2022. Screening Australia’s Basins for CO2-Enhanced Oil Recovery (December 6, 2022). <i>Proceedings of the 16th Greenhouse Gas Control Technologies Conference (GHGT-16) 23-24 Oct 2022</i>, Available at SSRN: <a href="https://ssrn.com/abstract=4294743">https://ssrn.com/abstract=4294743</a> or <a href="http://dx.doi.org/10.2139/ssrn.4294743">http://dx.doi.org/10.2139/ssrn.4294743</a>