<div>The Australian Government's Trusted Environmental and Geological Information program is a collaboration between Geoscience Australia and CSIRO. Part of this program includes baseline geological and environmental assessments. </div><div> Hydrogeological information has been collated for the Adavale, Cooper, Galilee and north Bowen basins and overlying basins, including the Eromanga and Lake Eyre basins. This information will provide a regionally-consistent baseline dataset that will be used to develop groundwater conceptualisation models.</div><div> Publicly-available data within these basin regions have been compiled from over 30&nbsp;000 boreholes, 120 stream gauges, and 1100 rainfall stations, resulting in revised hydrostratigraphic frameworks. From the published literature, 14 major hydrostratigraphic units are recognised within the basin regions. For each of these major hydrostratigraphic units, we determined the salinity, Darcian yield, specific yield/storativity, groundwater reserve volume for unallocated groundwater, groundwater levels/hydrological pressure, likelihood of inter-aquifer connectivity, rainfall, connectivity between surface water and groundwater, and water-use volume statistics, where relevant, for each basin, hydrogeological province and aquifer. We then adopted a play-based approach to develop holistic hydrostratigraphic conceptualisations of the basin regions. </div><div> Within the Adavale Basin we have defined a new hydrogeological province including two new aquifers defined as the moderate salinity and moderately overpressured Buckabie-Etonvale Aquifer, and the hypersaline and hyper-overpressured Lissoy-Log Creek-Eastwood Aquifer. Similarities between the upper Buckabie-Etonvale Aquifer of the Adavale Basin and lowermost Joe Joe Group of the Galilee Basin suggests connectivity between the upper Adavale and lower Galilee basins. Hydraulic pressures (up to 1500 m of excess freshwater head) calculated for the Lissoy–Log Creek–Eastwood Aquifer indicate that if the aquifer was to be breached, there is potential localised risk to overlying aquifers and surface environments, including infrastructure.</div><div><br></div><div><strong>Author Biography:</strong></div><div>Dr. Chris Gouramanis is a hydrogeologist working in the Trusted Environmental and Geological Information program, in the Minerals, Energy and Groundwater Division of Geoscience Australia. Chris was awarded his PhD from The Australian National University in 2009 and has held several water and environmental policy positions within the Australian Government. He worked for 10 years as an academic at the Earth Observatory of Singapore and the Geography Department at the National University of Singapore. He is also Australia’s National Focal Point to the Scientific and Technical Review Panel of the Ramsar Convention on Wetlands.</div><div><br></div>This Abstract was submitted/presented to the 2022 Australasian Groundwater Conference 21-23 November (https://agc2022.com.au/)

<div>The Groundwater Dependent Ecosystem (GDE) Atlas (Bureau of Meteorology, 2019) is a well-known national product that has been utilised for a wide range of applications including environmental impact statements, water planning and research. A complementary GDE dataset, Groundwater Dependent Waterbodies (GDW), has been produced from Digital Earth Australia (DEA) national data products. This new GDW ArcGIS dataset is spatially aligned with Landsat satellite-derived products, enabling ready integration with other spatial data to map and characterise GDEs across the continent.</div><div><br></div><div>The DEA Water Observations Multi Year Statistics (Mueller et al. 2016; DEA 2019) and the DEA Waterbodies (version 2) data product (Kraus et al., 2021; DEA Waterbodies, 2022) have been combined with the national GDE Atlas to produce the GDW dataset which delineates surface waterbodies that are known and/or high potential aquatic GDEs. The potential of a GDE relates to the confidence that the mapped feature is a GDE, where known GDEs have been mapped from regional studies and high potential GDEs identified from regional or national studies (Nation et al., 2017). The GDW dataset are aquatic GDE waterbodies, including springs, rivers, lakes and wetlands, which rely on a surface expression of groundwater to meet some or all of their water requirements. </div><div><br></div><div>The DEA Water Observation Multi Year Statistics, based on Collection 3 Landsat satellite imagery, shows the percentage of wet observations in the landscape relative to the total number of clear observations since 1986. DEA Waterbodies identifies the locations of waterbodies across Australia that are present for greater than 10% of the time and are larger than 2700m2 (3 Landsat pixels) in size. These waterbodies include GDEs and non-GDEs (e.g. surface water features not reliant on groundwater, such as dams). Where known/high potential GDEs in the GDE Atlas intersected a DEA waterbody, the entire waterbody polygon was assigned as a potential GDW, resulting in 55,799 waterbodies in the GDW dataset. Conversely, any GDEs not classified as known/high potential GDEs in the Atlas, due to a lack of data, are not included in the GDW product. Even though this method should remove dams from the GDW dataset (assuming they have been assigned appropriately in the GDE Atlas), due to spatial misalignment some may still be included that are not potential GDEs. Furthermore, surface water features that are too small to be detected by Landsat satellite data will be excluded from the GDW dataset.</div><div><br></div><div>The GDW polygons were attributed with the spatial summary of maximum, median, mean and minimum percentages for pixels within each GDW, derived from the DEA Water Observation Multi Year Statistics i.e. maximum/minimum pixel value or median/mean across all pixels in the GDW. This attribute enables comparison between GDWs of the proportion of time they have surface water observed. An additional attribute was added to the GDW dataset to indicate amount of overlap between waterbodies and aquatic GDEs in the GDE Atlas.&nbsp;</div><div><br></div><div>An ESRI dataset, AquaticGDW.gdb, and a variety of national ArcGIS layer files have been produced using the spatial summary statistics in the GDW dataset.</div><div>These provide a first-pass representation of known/high potential aquatic GDEs and their surface water persistence, derived consistently from Landsat satellite imagery across Australia.</div><div><br></div><div><strong>References:</strong></div><div> </div><div>Bureau of Meteorology, 2019. <em>Groundwater Dependent Ecosystems Atlas</em>. http://www.bom.gov.au/water/groundwater/gde/index.shtml </div><div>&nbsp;</div><div>DEA Water Observations Statistics, 2019. https://cmi.ga.gov.au/data-products/dea/686/dea-water-observations-statistics-landsat</div><div><br></div><div>DEA Waterbodies, 2022. https://www.dea.ga.gov.au/products/dea-waterbodies</div><div><br></div><div>Krause, C.E., Newey, V., Alger, M.J., and Lymburner, L., 2021. Mapping and Monitoring the Multi-Decadal Dynamics of Australia’s Open Waterbodies Using Landsat, <em>Remote Sensing</em>, 13(8), 1437. https://doi.org/10.3390/rs13081437</div><div><br></div><div>Mueller, N., Lewis, A., Roberts, D., Ring, S., Melrose, R., Sixsmith, J., Lymburner, L., McIntyre, A., Tan, P., Curnow, S. and Ip, A., 2016. Water observations from space: Mapping surface water from 25 years of Landsat imagery across Australia. <em>Remote Sensing of Environment</em>, 174, 341-352, ISSN 0034-4257.</div><div><br></div><div>Nation, E.R., Elsum, L., Glanville, K., Carrara, E. and Elmahdi, A., 2017. Updating the Atlas of Groundwater Dependent Ecosystems in response to user demand, 22nd International Congress on Modelling and Simulation, Hobart, Tasmania, mssanz.org.au/modsim2017</div>

<div>Geoscience Australia's Exploring for the Future Program (EFTF) is supporting regional and national-scale initiatives to address Australia’s hydrogeological challenges using an integrated geoscience systems approach. An important early step in the EFTF groundwater program focused on developing a national hydrogeological inventory of Australia’s major groundwater basins and fractured rock provinces. The inventory has its roots in the seminal 1987 Hydrogeology of Australia map, the first continental-scale map of groundwater systems and principal aquifers (Jacobson and Lau, 1987). Seeking to enhance and modernise the supporting information base for the national map, the inventory combines a curated selection of geospatial data attributes supported by focused narrative on the geology and hydrogeology of each basin and fractured rock province.</div><div>&nbsp;</div><div>The national hydrogeological inventory has a broad range of benefits for Australian groundwater users, managers and policy makers. These include the provision of an updated knowledge base covering the hydrogeology and groundwater systems of the major hydrogeological provinces of the nation, as well as important contextual information. The extensive catalogue of knowledge contained in the inventory also enables an objective approach to identify and prioritise areas for further regional assessment.</div><div>&nbsp;</div><div>Based on analysis of data compiled for the national inventory, the Lake Eyre Basin in arid central Australia was the first region prioritised for more detailed hydrogeological assessment during EFTF. The integration of a variety of basin- to national-scale geoscience datasets enabled significant advances in geological and hydrogeological understanding and the development of a new geological model for the three main basin depo-centres, namely the Tirari and Callabonna Sub-basins, and the Cooper Creek Palaeovalley. The geological modelling has further supported a range of hydrogeological applications, including substantial improvements in the number of bores with aquifer attribution, as well as the first regional watertable map across the basin. Abstract submitted and presented at the 2023 AGC NZHS Joint Conference Auckland, NZ (https://www.agcnzhs2023conference.co.nz/)

<div>Groundwater is critical to the survival of a range of ecosystems in Australia through provision of a direct source of water to plants with suitable root systems, and through discharge into surface water systems. Effectively managing groundwater dependent ecosystems (GDEs) alongside other water demands requires the ability to identify, characterise, and monitor vegetation condition.&nbsp;<em>&nbsp;</em><br> As part of the <a href="https://www.eftf.ga.gov.au/upper-darling-river-floodplain-groundwater-study">Exploring for the Future Upper Darling Floodplain</a> (UDF) groundwater project in western New South Wales, we present results from a study testing the suitability of two novel methods (a) recently available tasselled cap percentile products with national coverage through Digital Earth Australia, and (b) dry-conditions interferometric radar (InSAR) coherence images for mapping vegetation that is potentially groundwater dependent. <em>&nbsp;</em></div><div><em>&nbsp;</em></div><div>A combination of greenness and wetness 10th percentile tasselled cap products delineated terrestrial and aquatic GDEs with greater accuracy than existing regional ecosystem mapping, demonstrating the utility of these products for GDE identification. These results suggest the tasselled cap products can be used to support and refine the existing GDE mapping for this region, and further testing of their suitability and application for other regions is warranted.&nbsp;<em>&nbsp;</em></div><div><em>&nbsp;</em></div><div>The InSAR coherence images produced good agreement with the Bureau of Meteorology national GDE Atlas for areas of high probability of groundwater dependence. Although data availability and technical expertise currently lags behind optical imagery products, if research continues to show good performance in mapping potential GDEs and other applications, InSAR could become an important line of evidence within multi-dataset investigations.&nbsp;<em>&nbsp;</em></div><div><em>&nbsp;</em></div><div>Key next steps for improving the utility of these techniques &nbsp;are (a) comparison with vegetation condition data, and (b) further assessment of the likelihood of groundwater dependence through assessing relationships between vegetation condition and groundwater, surface water, and soil moisture availability.<em>&nbsp;</em></div><div>&nbsp;</div><div>This abstract was submitted/presented to the 2023 Australasian Groundwater / New Zealand Hydrological Society (AGC NZHS) Joint Conference (https://www.hydrologynz.org.nz/events-1/australasian-groundwater-nzhs-joint-conference)</div>

<div>The Darling River is the primary water source for communities on the Upper Darling River Floodplain (UDF) in arid northwest New South Wales. A 70% reduction in mean annual flow down the Darling over the past 80 years, due to droughts and over-extraction, has resulted in critical water shortages and water quality issues for communities and ecosystems. Presently there is a limited understanding of the spatial extent and controls on the occurrence of lower salinity groundwater within the surrounding Darling Alluvium; a possible&nbsp;alternative water source that is also important to groundwater-dependent ecosystems.</div><div>&nbsp;</div><div>The UDF project, part of the Australian Government’s Exploring for the Future program is working in collaboration with State partners to collect and integrate new data with existing hydrogeological knowledge. The project aims to improve the hydrogeological understanding of the region to help inform water management decisions and increase water security. A key focus of the project is the Darling Alluvium (DA)—a closed regional groundwater system comprising unconsolidated Cenozoic sediments deposited primarily by the paleo and current Darling River systems and their tributaries. Connectivity with aquifers of varying quality, within the underlying Murray and Great Artesian Basins, is also being investigated. </div><div>&nbsp;</div><div>Integration of airborne electromagnetic (AEM), hydrometric and hydrochemical data with lithology logs and geological maps has revealed a broad trend in groundwater–surface water dynamics. In the upper reaches of the floodplain systems appear to be disconnected, while in the lower reaches losing stream conditions prevail. In the losing stream setting, resistive AEM signatures, at depths of up to 60 m below ground level and extending laterally for several hundred metres from the river, indicate a hydraulic gradient away from the river. Low salinity groundwater measured in shallow bores suggest the potential for a significant quality groundwater resource. Further investigations will improve confidence in the geometry of fresh water zones, recharge rates, connectivity with underlying saline aquifers and relationships with groundwater-dependent ecosystems.&nbsp;</div><div><br></div>This Abstract was submitted/presented to the 2022 Australasian Groundwater Conference 21-23 November (https://www.aig.org.au/events/australasian-groundwater-conference-2022/)

<div>The Lake Eyre surface water catchment covers around 1,200,000 km2 of central Australia, about one-sixth of the entire continent. It is one of the largest endorheic river basins in the world and contains iconic arid streams such as the Diamantina, Finke and Georgina rivers, and Cooper Creek. The Lake Eyre region supports diverse native fauna and flora, including nationally significant groundwater-dependent ecosystems such as springs and wetlands which are important cultural sites for Aboriginal Australians.</div><div><br></div><div>Much of the Lake Eyre catchment is underlain by the geological Lake Eyre Basin (LEB). The LEB includes major sedimentary depocentres such as the Tirari and Callabonna sub-basins which have been active sites of deposition throughout the Cenozoic. The stratigraphy of the LEB is dominated by the Eyre, Namba and Etadunna formations, as well as overlying Pliocene to Quaternary sediments.</div><div><br></div><div>The National Groundwater Systems Project, part of Geoscience Australia's Exploring for the Future Program (https://www.eftf.ga.gov.au/), is transforming our understanding of the nation's major aquifer systems. With an initial focus on the Lake Eyre Basin, we have applied an integrated geoscience systems approach to model the basin's regional stratigraphy and geological architecture. This analysis has significantly improved understanding of the extent and thickness of the main stratigraphic units, leading to new insights into the conceptualisation of aquifer systems in the LEB.</div><div><br></div><div>Developing the new understanding of the LEB involved compilation and standardisation of data acquired from thousands of petroleum, minerals and groundwater bores. This enabled consistent stratigraphic analysis of the major geological surfaces across all state and territory boundaries. In places, the new borehole dataset was integrated with biostratigraphic and petrophysical data, as well as airborne electromagnetic (AEM) data acquired through AusAEM (https://www.eftf.ga.gov.au/ausaem). The analysis and integration of diverse geoscience datasets helped to better constrain the key stratigraphic horizons and improved our overall confidence in the geological interpretations.</div><div><br></div><div>The new geological modelling of the LEB has highlighted the diverse sedimentary history of the basin and provided insights into the influence of geological structures on modern groundwater flow systems. Our work has refined the margins of the key depocentres of the Callabonna and Tirari sub-basins, and shown that their sediment sequences are up to 400 m thick. We have also revised maximum thickness estimates for the main units of the Eyre Formation (185 m), Namba Formation (265 m) and Etadunna Formation (180 m).</div><div><br></div><div>The geometry, distribution and thickness of sediments in the LEB is influenced by geological structures. Many structural features at or near surface are related to deeper structures that can be traced into the underlying Eromanga and Cooper basins. The occurrence of neotectonic features, coupled with insights from geomorphological studies, implies that structural deformation continues to influence the evolution of the basin. Structures also affect the hydrogeology of the LEB, particularly by compartmentalising groundwater flow systems in some areas. For example, the shallow groundwater system of the Cooper Creek floodplain is likely segregated from groundwater in the nearby Callabonna Sub-basin due to structural highs in the underlying Eromanga Basin.</div><div> Abstract submitted and presented at the 2023 Australian Earth Science Convention (AESC), Perth WA (https://2023.aegc.com.au/)

This report presents groundwater level information collected during Geoscience Australia’s Musgrave Palaeovalley Project. The Musgrave Palaeovalley Project was conducted as part of Exploring for the Future (EFTF), an Australian Government funded geoscience data and information acquisition program. The eight-year, $225 million program aims to deliver new geoscience data and knowledge to inform decision-making by government, community, and industry on the sustainable development of Australia's mineral, energy, and groundwater resources.</div><div>Groundwater level data was collected during two hydrogeochemical surveys undertaken in March and May 2023 based around the remote communities of Warburton, Kaltukatjara, Wanarn, Blackstone and Jameson in Western Australia and the Northern Territory. Sixteen bores were measured for their groundwater levels. The results are contained herein and within the attached CSV file.

This was the third of five presentations held on 31 July 2023 as part of the National Groundwater Systems Workshop - WaMSTeC: Water Monitoring and Standardisation Technical Committee National Industry Guidelines for hydrometric monitoring WaMSTeC GUIDELINE REVISIONS UPDATE FOR GROUNDWATER COMPONENTS: GROUNDWATER SUBCOMMITTEE

<div>The Exploring for the Future program is a world leading program, delivering public geoscientific data and information required to empower decision-makers and attract future investment in resource exploration and development. Geoscience Australia engaged Alluvium Consulting Australia to quantify the impact and value of groundwater activities and outputs to the quadruple bottom line through an evaluation of 2 case studies, namely: • National Hydrogeological Mapping • The Southern Stuart Corridor project. This involved understanding the impact pathways for these case studies and the collection of data to be used in a cost benefit analysis. The work sought to provide feedback to Geoscience Australia, stakeholder groups and the broader community on the value of Geoscience Australia’s groundwater activities. The case study evaluations were facilitated by a series of specific questions, which were developed to guide data collection and the building of a knowledge base around the impact and value of the work in each case study and associated outputs. The questions broadly fell under the following categories: 1. Uptake and Usage 2. Impact 3. Benefit These evaluations were framed around the program impact pathway developed for each case study. This is a description of how inputs are used to deliver activities, which in turn result in outcomes and impacts (changes) for stakeholders, including the environment. The primary means of data collection to help answer the key evaluation questions was through online workshops and interviews with key stakeholders for each case study. These were undertaken between March 10 and March 24, 2023. In these workshops and interviews, representatives from industry, community and government agencies were asked if they could identify instances where case study program outputs were used for particular purposes, such as prioritising research or investment, advising Members of Parliament, or education and training. These examples were then explored further to understand what outcomes and benefits were derived from the use of the case study outputs, and how critical were the case study outputs to achieving those outcomes and benefits</div>

<div>This study investigates the feasibility of mapping potential groundwater dependent vegetation (GDV) at a regional scale using remote sensing data. Specifically, the Digital Earth Australia (DEA) Tasseled Cap Percentiles products, integrated with the coefficient of greenness and/or wetness, are applied in three case study regions in Australia to identify and characterise potential terrestrial and aquatic groundwater dependent ecosystems (GDE). The identified high potential GDE are consistent with existing GDE mapping, providing confidence in the methodology developed. The approach provides a consistent and rapid first-pass approach for identifying and assessing GDEs, especially in remote areas of Australia lacking detailed GDE and vegetation information.</div>