Background: Australia has a highly dynamic coastline of over 30,000 km, with over 85% of its population living within 50 km of the coast. This coastline is subject to a wide range of pressures, including extreme weather and climate, sea level rise and human development. Understanding how the coastline responds to these pressures is crucial to managing this region, from social, environmental and economic perspectives. What this product offers: Digital Earth Australia Coastlines is a continental dataset that includes annual shorelines and rates of coastal change along the entire Australian coastline from 1988 to the present. The product combines satellite data from Geoscience Australia's Digital Earth Australia program with tidal modelling to map the typical location of the coastline at mean sea level for each year. The product enables trends of coastal erosion and growth to be examined annually at both a local and continental scale, and for patterns of coastal change to be mapped historically and updated regularly as data continues to be acquired. This allows current rates of coastal change to be compared with that observed in previous years or decades. The ability to map shoreline positions for each year provides valuable insights into whether changes to our coastline are the result of particular events or actions, or a process of more gradual change over time. This information can enable scientists, managers and policy makers to assess impacts from the range of drivers impacting our coastlines and potentially assist planning and forecasting for future scenarios. Applications - Monitoring and mapping rates of coastal erosion along the Australian coastline - Prioritise and evaluate the impacts of local and regional coastal management based on historical coastline change - Modelling how coastlines respond to drivers of change, including extreme weather events, sea level rise or human development - Supporting geomorphological studies of how and why coastlines have changed across time

The Australian Government is investing in a world first analysis platform for satellite imagery and other Earth observations. From sustainably managing the environment to developing resources and optimising our agricultural potential, Australia must overcome a number of challenges to meet the needs of our growing population. Digital Earth Australia (DEA) will deliver a unique capability to process, interrogate, and present Earth observation satellite data in response to these issues. It will track changes across Australia in unprecedented detail, identifying soil and coastal erosion, crop growth, water quality, and changes to cities and regions. DEA will build on the globally recognised innovation, the Australian Geoscience Data Cube1; which was the winner of the 2016 Content Platform of the Year at the Geospatial World Leadership Awards and was developed as a partnership between GA, CSIRO and the National Collaborative Research Infrastructure Strategy (NCRIS) supported National Computational Infrastructure (NCI).

<div>This report provides an assessment of the viability of Managed Aquifer Recharge (MAR) as a potential supplementary water supply for the township of Wilcannia in the Upper Darling River Floodplain (UDRF) region of northwest New South Wales, Australia, in addition to existing emergency water supply bores and a proposed replacement weir across the Darling River. The Baaka is the traditional name for the Darling River by the Barkindji people. </div><div>This study was completed during the UDRF Project, as part of the Exploring for the Future (EFTF) program—an eight-year, $225 million Australian Government funded geoscience data and information acquisition program focused on better understanding the potential of mineral, energy and groundwater resources across Australia. </div><div>The UDRF region's heavy reliance on surface water results in inadequate water security during drought, affecting economic prospects, community welfare, and the environment. Geoscience Australia, in partnership with the New South Wales Department of Climate Change, Energy, the Environment and Water (DCCEEW), has undertaken the UDRF Project with the aim of improving groundwater system understanding, assessing groundwater-surface water connectivity, and investigating potential MAR options to enhance drought resilience. </div><div>A MAR scheme is a sustainable proposition in the area compared to groundwater extraction without replenishment, as the semi-confined aquifer doesn’t necessarily represent a viable water resource due to natural recharge of this aquifer taking hundreds of years. As part of the UDRF project, analyses of the hydrodynamic data show that the Darling River is strongly connected to the groundwater systems in the study area, specifically the shallow unconfined aquifers of the Menindee/Coonambidgal Formations and the semi-confined Calivil Formation. The permeable sand-rich unconfined aquifers facilitated groundwater recharge during high river flow periods. Groundwater quality assessments indicate fresh to moderately saline water in the shallower formations, with significantly higher salinity observed in the deeper Renmark Group.</div><div>Four areas potentially suitable for a MAR scheme were identified within the Darling River valley from 2 km to 30 km upstream of Wilcannia, and were delineated through the integrated interpretation of datasets including regional airborne electromagnetics (AEM), ground-based and borehole geophysics, hydrodynamics and hydrochemistry. The four MAR targets were identified based on AEM conductivity threshold of 0.06 S/m, and the borehole water chemistry supports a water quality of &lt;1,200 mg/L TDS (i.e. good to acceptable quality). For a MAR scheme, selecting an area with acceptable quality groundwater is important as the quality of the injected water can remain as acceptable following mixing with the in-situ groundwater. </div><div>Geophysical surveys, including surface magnetic resonance and downhole natural gamma and nuclear magnetic resonance logs, highlight the potential suitability of sand facies within the Calivil Formation as storage aquifer for MAR.&nbsp;Interpretation of AEM models across the four MAR targets suggests that the Calivil Formation aquifer extends beyond the target boundaries and could provide the storage capacity to hold injected water. Additional storage capacity from operating a MAR scheme can only be assessed by a local injection and extraction pilot study.</div><div>In a semi-confined aquifer such as the Calivil Formation, injection of water increases the hydraulic pressure and pushes the acceptable quality in-situ groundwater outwards from the injection sites, displacing the surrounding saline groundwater. The in-situ groundwater of acceptable quality then forms a buffer zone around the injected water, and this improves the recovery efficiency by minimising the flow of saline groundwater towards the extraction well. </div><div>MAR Target 1 is recommended as a potential pilot study area owing to its proximity to Wilcannia and the availability of existing utility infrastructure, such as electricity. Potential sites within the target area were identified for riverbank filtration and Aquifer Storage and Recovery (ASR) wells, considering proximity to the river, groundwater quality, and infrastructure requirements. Proposed ASR sites target the Calivil Formation aquifer, and two of these sites have Paleozoic bedrock directly underlying this storage aquifer. The bedrock acts as an aquitard and minimises the risk of saline groundwater ingress from the Renmark Group, which is present in a palaeovalley adjacent to the two proposed sites.&nbsp;</div><div>If MAR is to be further considered in the region the report offers recommendations for future studies, including the development of pilot ASR sites with drilling to more accurately characterise the sedimentary sequence and the aquifer lithology, and assess the viability of any proposed system.&nbsp;</div>

The Exploring for the Future program Showcase 2024 was held on 13-16 August 2024. Day 4 - 16th August talks included: <b>Session 1 – Deep Dives into the Delamerian</b> <a href="https://youtu.be/09knAwPnD7s?si=acdu6pQgIj7DNlnj">Scaffold to success: An overview of the Delamerian Orogen, and its crustal and lithospheric architecture</a> - Chris Lewis <a href="https://youtu.be/5GQC5f5IkWc?si=rLPqxoZFkxGAEPEf">Only time will tell: Crustal development of the Delamerian Orogen in space and time</a> - David Mole <a href="https://youtu.be/PhdIYE49eqU?si=d7acyv5rbTW_wTiO">Is it a big deal? New mineral potential insights of the Delamerian Orogen</a> - Dr Yanbo Cheng <b>Session 2 – Deep dives into Birrindudu, West Musgrave and South Nicholson–Georgina regions</b> <a href="https://youtu.be/DEbkcgqwLE8?si=sBKGaMTq_mheURib">Northwest Northern Territory Seismic Survey: Resource studies and results</a> - Paul Henson <a href="https://youtu.be/k9vwBa1fM9E?si=VOG19nBC1DAk-jGH">Tracing Ancient Rivers: A hydrogeological investigation of the West Musgrave Region</a> - Joshua Lester <a href="https://youtu.be/Du1JANovz8M?si=1XEOF87gxhSP9UF3">Water's journey: Understanding groundwater dynamics in the South Nicholson and Georgina basins, NT and QLD </a>- Dr Prachi Dixon-Jain <b>Session 3 – Groundwater systems of the Curnamona and upper Darling-Baaka River</b> <a href="https://youtu.be/nU8dpekmEHQ?si=WygIzefKNzsU4gUA">Groundwater systems of the upper Darling-Baaka floodplain: An integrated assessment</a> - Dr Sarah Buckerfield <a href="https://youtu.be/AKOhuDEPxIA?si=ebradAT6EBwHhPQ_">Potential for a Managed Aquifer Recharge Scheme in the upper Darling-Baaka floodplain: Wilcannia region</a> - Dr Kok Piang Tan <a href="https://youtu.be/epUdD8ax2FQ?si=_aMO_e_ZDZESgLOR">Aquifer alchemy: Decoding mineral clues in the Curnamona region</a> - Ivan Schroder Exploring for the Future: Final reflection – Karol Czarnota Resourcing Australia’s Prosperity – Andrew Heap View or download the <a href="https://dx.doi.org/10.26186/149800">Exploring for the Future - An overview of Australia’s transformational geoscience program</a> publication. View or download the <a href="https://dx.doi.org/10.26186/149743">Exploring for the Future - Australia's transformational geoscience program</a> publication. You can access full session and Q&A recordings from YouTube here: 2024 Showcase Day 4 - Session 1 - <a href="https://www.youtube.com/watch?v=4nuIQsl71cY">Deep Dives into the Delamerian</a> 2024 Showcase Day 4 - Session 2 - <a href="https://www.youtube.com/watch?v=9N3dIZRAcHk">Deep dives into Birrindudu, West Musgrave and South Nicholson–Georgina regions</a> 2024 Showcase Day 4 - Session 3 - <a href="https://www.youtube.com/watch?v=_ddvLAnUdOI">Groundwater systems of the Curnamona and upper Darling-Baaka River</a>