The integrated use of seismic and gravity data can help to assess the potential for underground hydrogen storage in salt caverns in the offshore Polda Basin, South Australia. Geophysical integration software was trialled to perform simultaneous modelling of seismic amplitudes and traveltime information, gravity, and gravity gradients within a 2.5D cross-section. The models were calibrated to existing gravity data, seismic and well logs improving mapping of the salt thickness and depth away from well control. Models included known salt deposits in the offshore parts of the basin and assessed the feasibility for detection of potential salt deposits in the onshore basin, where there is limited well and seismic coverage. The modelling confirms that candidate salt cavern storage sites with salt thicknesses greater than 400-500 m should be detectable on low altitude airborne gravity surveys. Identification of lower cost onshore storage sites will require careful calibration of gravity models against measured data, rather than relying on the observation of rounded anomalies associated with salt diapirism. Ranking of the most prospective storage sites could be optimized after the acquisition of more detailed gravity and gradiometry data, preferably accompanied by seismic reprocessing or new seismic data acquisition.

The Adavale Basin, home to the Boree Salt, is a potential option for underground hydrogen storage (UHS) due to its close proximity to industrial infrastructure, existing pipelines and significant renewable energy sources. This study builds upon a previously constructed 3D geological model to examine the feasibility of developing salt caverns for UHS. The study integrates well data and regional geology, as well as analyses on mineralogy, geochemistry and petrophysical and geomechanical properties of the Boree Salt. Results highlight that the Boree Salt is predominantly halite (96.5%), with a net salt thickness of ~540 m encountered in Bury 1, and has excellent seal properties. Furthermore, the formation overburden pressure gradient implies favourable conditions for storing hydrogen in the Boree Salt. To illustrate the feasibility of UHS, a conceptual design of a cylindrical salt cavern at depth intervals of 1600 – 1950 m is presented. A single 60 m diameter cavern could provide up to 203 GWh (or ~ 6000 tonnes) of hydrogen energy storage. Further investigation to improve our understanding on the Boree Salt extent is recommended.

<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/)

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.

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

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.

The ‘Australia’s Future Energy Resources’ (AFER) project is a four-year multidisciplinary investigation of the potential energy commodity resources in selected onshore sedimentary basins. The resource assessment component of the project incorporates a series of stacked sedimentary basins in the greater Pedirka-western Eromanga region in eastern central Australia. Using newly reprocessed seismic data and applying spatially enabled, exploration play-based mapping tools, a suite of energy commodity resources have been assessed for their relative prospectivity. One important aspects of this study has been the expansion of the hydrocarbon resource assessment work flow to include the evaluation of geological storage of carbon dioxide (GSC) opportunities. This form of resource assessment is likely to be applied as a template for future exploration and resource development, since the storage of greenhouse gases has become paramount in achieving the net-zero emissions target. It is anticipated that the AFER project will be able to highlight future exploration opportunities that match the requirement to place the Australian economy firmly on the path of decarbonisation.

<div>Carbon capture and storage (CCS) is gaining momentum globally. The Global CCS Institute notes in their Status of CCS 2023 report that there are 26 carbon capture and storage projects under construction and a further 325 projects in development, with a total capture capacity of 361 million tonnes per year (Mt/y) of carbon dioxide (CO2). Some CCS projects require the extraction of brackish or saline water (referred to here on in as brine) from the storage formation to manage increased pressure resulting from CO2 injection and/or to optimise subsurface storage space. It is important to consider the management of extracted brine as the CCS industry scales up due to implications for project design, cost and location as well as for the responsible management of the ‘waste’ or by-product brine. The use and disposal of reservoir brine has been investigated for CCS projects around the world, but not for Australian conditions. We have undertaken this review to explore how extracted brine could potentially be managed by CCS projects across Australia.&nbsp;</div>

Natural hydrogen is receiving increasing interest as a potential low-carbon fuel. There are various mechanisms for natural hydrogen generation but the reduction of water during oxidation of iron in minerals is recognised to be the major source of naturally generated H2. While the overall reaction is well known, the identity and nature of the key rate limiting steps is less understood. This study investigates the dominant reaction pathways through the use of kinetic modelling. The modelling results suggest there are a number of conditions required for effective H2 production from iron minerals. These include the presence of ultramafic minerals that are particularly high in Fe rather than Mg content, pH in the range of 8 to 10, solution temperatures in the 200 to 300oC range, and strongly reducing conditions. High reaction surface area is key and this could be achieved by the presence of finely deposited material and/or assemblages of high porosity or with mineral assemblages with surface sites that are accessible to water. Finally, conditions favouring the co-deposition of Ni together with FeO/Fe(OH)2-containing minerals such as brucite (and, possibly, magnetite) could enhance H2 generation

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.