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  • <div>This short video of less than two minutes duration depicts the history of magmatism through time across the Australian continent, from 3.5 billion years ago to the present. The video is based on publicly-available geochronological data that has been compiled within the Interpreted Ages module of the ISOTOPES database, and delivered through the GA Portal via the Geochronology and Isotopes persona.</div>

  • The National Groundwater Systems (NGS) project, is part of the Australian Government’s Exploring for the Future (EFTF) program, led by Geoscience Australia (https://www.eftf.ga.gov.au/national-groundwater-systems), to improve understanding of Australia’s groundwater resources to better support responsible groundwater management and secure groundwater resources into the future. The project is developing new national data coverages .to further delineate groundwater systems and improve data standards and workflows of groundwater assessment. While our conceptual understanding of the hydrogeology of the Great Artesian Basin (GAB, Figure 1) continues to grow, in many parts of the Eromanga, Surat and Carpentaria basins that form the GAB we are still reliant on legacy data and knowledge from the 1970s of variable quality. Additional information provided by recent studies in various parts of the GAB highlights the level of architectural complexity and spatial variability in stratigraphic and hydrostratigraphic units across the basin. We now recognise the need to standardise these regional studies to map such geological complexity in a consistent, basin-wide hydrostratigraphic framework that can support effective long-term management of GAB water resources. The recent iteration of revision of GAB geological and hydrogeological surfaces (Vizy & Rollet, 2022) provides a framework to interpret various data sets consistently (e.g., boreholes, airborne electromagnetic, seismic data) and in a 3D domain, to improve the aquifer geometry, and the lateral variation and connectivity in hydrostratigraphic units across the GAB (Rollet et al., 2022). Vizy and Rollet (2022) highlighted some areas with low confidence in the interpretation of the GAB where further data acquisition or interpretation may reduce uncertainty in the mapping. One of these areas was in the Carpentaria Basin, particularly the transition from the offshore to onshore across the Gulf of Carpentaria. This data compilation provides open file SEGY, cultural data and value added seismic interpretation in the form of seismic horizons and grids for two key surfaces, these enable improved correlation to existing studies. This data also aim to provide users an efficient mean to rapidly access core data from numerous sources in a consistent and cleaned format, all in a single package. This dataset provides: 1) Seismic data compilation in a digital format with publically accessible information, including scanned seismic sections converted to SEGY format where digital data was not available; 2) Base Mesozoic and Near Base Cenozoic seismic interpretation in two-way-time; 3) Depth converted regional surfaces for the Base Mesozoic and Near Base Cenozoic unconformities generated using additional constraints such as AEM interpretation and borehole constraints previously compiled in Vizy & Rollet (2022). This new interpretation will be used to refine the GAB geological and hydrogeological surfaces in this region.

  • <div>This data package contains the main hydrogeological datasets compiled, analysed, developed, and used for the Geoscience Australia project that investigated the Cenozoic geology, hydrogeology, and groundwater systems of the Kati Thanda - Lake Eyre Basin in central Australia. This work, which was published as Geoscience Australia Record 2024/05 (Evans et al. 2024), was delivered as part of the National Groundwater Systems project in the Exploring for the Future program.</div><div><br></div><div>The hydrogeological and groundwater data includes new aquifer and aquifer province attribution for many thousands of groundwater bores, large-scale compilations of existing water level, salinity, and hydrogeochemical data, and new mapping of regional watertable trends and depth to standing water across the basin. These data are represented within the Geoscience Australia Record as various maps and related diagrams.</div><div><br></div><div>Reference: Evans TJ, Bishop C, Symington NJ, Halas L, Hansen JWH, Norton CJ, Hannaford C and Lewis SJ (2024) Cenozoic geology, hydrogeology, and groundwater systems: Kati Thanda – Lake Eyre Basin, Record 2024/05, Geoscience Australia, Canberra, http://dx.doi.org/10.26186/147422.</div><div><br></div>

  • High-CO2 gas fields serve as important analogues for understanding various processes related to CO2 injection and storage. The chemical signatures, both within the fluids and the solid phases, are especially useful for elucidating preferred gas migration pathways and also for assessing the relative importance of mineral precipitation and/or solution trapping efficiency. In this paper, we present a high resolution study focused on the Gorgon gas field and associated Rankin Trend gases on Australia's North West Shelf. The gas data we present here display clear trends for CO2 abundance (mole %) and %- C CO2 both areally and vertically. The strong spatial variation of CO2 content and %- C and the interrelationship between the two suggests that processes were active to alter the two in tandem. We propose that these variations were driven by the precipitation of a carbonate phase, namely siderite, which is observed as a common late stage mineral. This conclusion is based on Rayleigh distillation modeling together with bulk rock isotopic analyses of core, which indicates that the late stage carbonate cements are related to the CO2 in the natural gases. The results suggest that a certain amount of CO2 may be sequestered in mineral form over short migration distances of the plume.

  • Geoscience Australia has recently completed the Bonaparte CO2 Storage project, an assessment of the CO2 storage potential of the Petrel Sub-basin. In 2009, two greenhouse gas assessment leases were released, PTRL-01 and PTRL-02, under the Offshore Petroleum and Greenhouse Gas Storage Act of 2006. Both are proximal to the developing LNG market in Darwin, as well as a number of hydrocarbon accumulations in the Bonaparte Basin. A key phase of the project was geological modelling to test CO2 injection scenarios. Initial 3D seismic horizon surfaces were generated to create a 'simple' geological model. A 'complex' geological model was built by integrating a structure model, which was depth converted. Subsequently, models were populated with reservoir properties such as Vshale, porosity and permeability. Palaeogeography maps were generated for all key stratigraphic units and were used to populate the model where well control was lacking. Using Permedia', CO2 migration simulations with randomly located injection wells were run on a high resolution model to study the migration pathways, major accumulations and the effects of vertical anisotropy. Smaller areas of interest were then identified to reduce the size of the model and allow fluid flow reservoir simulations study using Permedia' and CMG-GEM'. The later study estimated the practical injectivity, storage volume, reservoir pressure during and after CO2 injection.

  • An atmospheric greenhouse gas (GHG) monitoring station began operation in July 2010 near Emerald, Queensland. The station is part of a collaborative project between Geoscience Australia (GA) and CSIRO Marine and Atmospheric Research (CMAR) to establish and operate a high precision atmospheric monitoring facility for measurement of baseline greenhouse gases (GHG) in a high priority geological carbon dioxide storage region. The primary purpose of the station is to field test newly developed greenhouse gas monitoring technology and demonstrate best practice for regional baseline atmospheric monitoring appropriate for geological storage of carbon dioxide. The GHG records were to be used as a reference for monitoring of the atmosphere at a CO2 storage project, providing a baseline to quantify typical variations in the area and a background against which any anomalies in the immediate vicinity of the storage might be detected. The site chosen for the GHG atmospheric monitoring station is in the locality of Arcturus, 50 km southeast of Emerald in the Central Highlands, Queensland. Site selection was based on the recommendations of the Carbon Storage Taskforce's National Carbon Mapping and Infrastructure Plan, regional assessments of prospective basins, regional atmospheric modelling, and consultation with key stakeholders. The key driver for the stakeholder consultation group was to support early projects for large scale onshore geological storage. Both the Bowen and Surat basins were identified as potential early mover onshore storage regions by the group and suitable for a regional atmospheric monitoring station. During early 2010, ZeroGen had an active exploration program for geological storage and the site was eventually located approximately 8km upwind from the boundary of ZeroGen's most prospective storage area in the northern Denison Trough, part of the larger Bowen Basin. The Arcturus site and environs is representative of the activities and ecology of Queenslan's Central Highlands and the greenhouse gas signals are likely be influenced by cropping, pasture, cattle production, and gas and coal activities. These same activities are also likely to be dominant sources of greenhouse gases in the Surat Basin. Importantly, the site is secure, can be accessed via an existing road, is not subject to flooding, and has easy access to electrical lines that only required the installation of a transformer on an electric pole. A long lead time for new electricity connections at remote sites (potentially greater than 12 months) was identified as a key risk to the project. Negotiations with the electricity supplier resulted in connection in less than 4 months. An access agreement was negotiated with the landowner to enable the installation of the monitoring station and access to the site.

  • Geoscience Australia (GA) conducted a marine survey (GA0345/GA0346/TAN1411) of the north-eastern Browse Basin (Caswell Sub-basin) between 9 October and 9 November 2014 to acquire seabed and shallow geological information to support an assessment of the CO2 storage potential of the basin. The survey, undertaken as part of the Department of Industry and Science's National CO2 Infrastructure Plan (NCIP), aimed to identify and characterise indicators of natural hydrocarbon or fluid seepage that may indicate compromised seal integrity in the region. The survey was conducted in three legs aboard the New Zealand research vessel RV Tangaroa, and included scientists and technical staff from GA, the NZ National Institute of Water and Atmospheric Research Ltd. (NIWA) and Fugro Survey Pty Ltd. Shipboard data (survey ID GA0345) collected included multibeam sonar bathymetry and backscatter over 12 areas (A1, A2, A3, A4, A6b, A7, A8, B1, C1, C2b, F1, M1) totalling 455 km2 in water depths ranging from 90 - 430 m, and 611 km of sub-bottom profile lines. Seabed samples were collected from 48 stations and included 99 Smith-McIntyre grabs and 41 piston cores. An Autonomous Underwater Vehicle (AUV) (survey ID GA0346) collected higher-resolution multibeam sonar bathymetry and backscatter data, totalling 7.7 km2, along with 71 line km of side scan sonar, underwater camera and sub-bottom profile data. Twenty two Remotely Operated Vehicle (ROV) missions collected 31 hours of underwater video, 657 still images, eight grabs and one core. This catalogue entry refers to total sediment metabolism, bulk carbonate and mineral specific surface area measurements, and major and minor trace elements and carbon and nitrogen concentrations and isotopes in the upper 2 cm of seabed sediments.

  • Atmospheric tomography is a monitoring technique that uses an array of sampling sites and a Bayesian inversion technique to simultaneously solve for the location and magnitude of a gaseous emission. Application of the technique to date has relied on air samples being pumped over short distances to a high precision FTIR Spectrometer, which is impractical at larger scales. We have deployed a network of cheaper, less precise sensors during three recent large scale controlled CO2 release experiments; one at the CO2CRC Ginninderra site, one at the CO2CRC Otway Site and another at the Australian Grains Free Air CO2 Enrichment (AGFACE) facility in Horsham, Victoria. The purpose of these deployments was to assess whether an array of independently powered, less precise, less accurate sensors could collect data of sufficient quality to enable application of the atmospheric tomography technique. With careful data manipulation a signal suitable for an inversion study can be seen. A signal processing workflow based on results obtained from the atmospheric array deployed at the CO2CRC Otway experiment is presented.

  • GA contribution to CO2CRC. Report describes the work done to create a PETREL model of the Naylor Field proposed injection reservoir; eighteen appendicies.

  • In 2012, Geoscience Australia carried out marine environmental surveys in the Vlaming Sub-basin, Perth Basin (GA0334) and Petrel Sub-basin, Bonaparte Basin (GA0335). The purpose of these surveys was to gather pre-competitive geophysical and biophysical data on the seabed environments within targeted areas of the sub-basins to help with the assessment of CO2 storage potential. Over the duration of the Vlaming Sub-basin survey, approximately 650 km2 of multibeam sonar data and 2300 line km of sub-bottom profiler (SBP) data were collected. Also acquired was 6.65 km2 of sidescan sonar imagery, 4.25 km of video footage and 89 grab samples. More than 650 km2 of multibeam sonar data and 650 line km of multi-channel SBP data was acquired during the Petrel Sub-basin survey. A total of 114 sampling operations recovered shallow samples or video footage for sedimentological, biological and chemical analysis. These datasets have been used to investigate possible fluid pathways in the shallow subsurface geology. In the Petrel Sub-basin, banks, palaeo-channels, plains, ridges and pockmark fields characterise the seafloor. While in the Vlaming Sub-basin, a Holocene sediment-starved system was observed with shallow valleys, shallow terraces, sediment mega-ripples and prominent ridges on the seafloor. The complexity of these environments and the general spatial correlation between seabed features and the subsurface geology, suggest that a large number of processes have interacted to give rise to the present geomorphology of the continental shelves. These new datasets have been used to support the regional assessment of CO2 storage prospectivity in the Vlaming and Petrel sub-basins.