Geoscience Australia has undertaken a regional seismic mapping study of the offshore Otway Basin extending across the explored inner basin to the frontier deep-water region. Seismic interpretation covers over 18,000 line-km of new and reprocessed data acquired in the 2020 Otway Basin seismic program, over 40,000 line-km of legacy 2D seismic data and GA’s new 2023 Otway 3D post-stack Mega Merge seismic dataset. This work provides a new perspective on regional structural architecture and basin evolution and has important implications for hydrocarbon prospectivity of this region. This seminar was two short talks centring on the Otway Basin. <u>Post-stack 3D merging to fast-track regional interpretation - offshore Otway Basin case study, presented by Merrie-Ellen Gunning</u> This case study was to produce a regularised and seamless 3D dataset of the highest possible quality, for the offshore Otway Basin, within two-months. The input migrated volumes varied by data extent, migration methodology, angle range and grid orientation. Fourteen input volumes totalling 8,092 km2 were post-stack merged and processed to produce a continuous and consistent volume, enabling more efficient and effective interpretation of the region. The surveys were regularised onto a common grid, optimised for structural trend, prior to survey matching. A mis-tie analysis algorithm, applied over a time window optimised for interpretation of key events, was used to derive corrections for timing, phase and amplitude, using a reference. This was followed by time-variant spectral and amplitude matching to improve continuity between volumes. Additional enhancements including noise removal and lateral amplitude scaling were also applied. The final merged volume offers significant uplift over the inputs, providing better imaging of structure and events and dramatically improving the efficiency and quality of interpretation. This enables rapid reconnaissance of the area by explorers. <u>Structural architecture of the offshore Otway Basin presented by Chris Nicholson</u> We present new basin-scale isochore maps that show the distribution of the Cretaceous depocentres. Maps for the Lower Cretaceous Crayfish and Eumeralla supersequences, together with those recently published for the Upper Cretaceous Shipwreck and Sherbrook Supersequences, completes the set of isochore maps for the main tectonostratigraphic basin intervals. Mapping of basement involved faults has revealed structural fabrics that have influenced depocentre development. The tectonostratigraphic development of depocentres and maps of deep crustal units delineate crustal thinning trends related to late Cretaceous extension phases. This work highlights the need to review and update structural elements. For example, the boundary between the Otway and Sorell basins is now geologically constrained. The refinements to the tectonostratigraphic evolution of the Otway Basin presented here have important implications for the distribution and potential maturity of petroleum systems, especially with regard to heat flow associated with crustal extension.

<div>Report on expression of interest, assessment and identification process of case studies to be included in the Exploring for the Future Geoscience Knowledge Sharing Project Remote Community Education Module and Building Relationships with Aboriginal Peoples Modules. &nbsp;The Geoscience Knowledge Sharing Project is a pilot study to discover best practices to improve engagement with non-technical stakeholders. </div>

<div><em>Seabed geomorphology</em> describes the shape and evolution of underwater landscapes. These landscapes interact with ocean currents to create diverse marine habitats. Similar to geological maps on land, maps of seabed geomorphology are vital for making informed decisions to support the sustainable growth of our Ocean Economy.</div><div><br></div><div>As we gather more detailed seabed data and face increasing ocean pressures, there's a need for new, standardised maps that support consistent decision making at multiple scales and between administrative jurisdictions. Dr Rachel Nanson and an international team have developed a new seabed geomorphology classification system that is designed to simplify complex seabed interpretations into a map format that is accessible to a broad range of end users.</div><div><br></div><div>This approach is being adopted internationally and is currently being implemented by Geoscience Australia. We are using the method to map parts of Australia’s extensive Marine Park network and to support government to make informed decisions regarding Australia’s rapidly expanding Offshore Renewable Energy sector</div>

<div>The Australian wide airborne electromagnetic programme AusAEM stands as the largest survey of its kind aiming to cover the Australian continent at approximately 20 km line-spacing. It is transforming resource exploration, unveiling potential minerals and groundwater.&nbsp;</div><div><br></div><div>The open-access nature of AusAEM data and the modelling codes developed around it encourages collaboration between governments, industry, and academia, fostering a community focused on advancing geoscientific research and exploration.</div><div><br></div><div>Overall, the AusAEM program is an asset that can drive economic growth, support sustainable resource management, and enhance scientific understanding of Australia’s geological landscape.</div><div><br></div>

<div>The Trusted Environmental and Geological Information (TEGI) Program (2021-2023) was a multi-disciplinary program that brought together the geology, energy resources, groundwater, carbon and hydrogen storage, mineral occurrences, surface water and ecology for four Australian basin regions. This talk covers how the team leveraged their varied scientific expertise to deliver integrated scientific outcomes for the North Bowen, Galilee, Cooper and Adavale basin regions. This talk highlights the approach and importance of meaningful engagement with those that live in, work in, rely on and care for the regions. The story of the TEGI program outlines how a committed team, collaborating across Australia’s leading scientific organisations, delivered genuine impact during a time of political change.</div><div><br></div>

<div>Global steel demand is forecast to grow in the coming decades with continued development across Asia and Africa. Over the same period, the International Energy Agency suggests that the carbon intensity of steel production will need to decrease rapidly to align with projected pathways to net zero emissions by 2050. Balancing these competing priorities is a challenge that could shift global steelmaking business models. With abundant resources of both iron ore and metallurgical coal, Australia has benefited significantly from traditional steelmaking value chains. In the face of potential disruption, how should Australia navigate the challenges and opportunities accompanying the transition to ’green’ steel? How can geoscience help to identify and leverage Australia’s specific advantages?&nbsp;</div><div><br></div><div>The Green Steel Economic Fairways Mapper is a free, online tool that models the costs of hydrogen-based green ironmaking and steelmaking and maps how these costs vary across Australia. Developed through collaboration between Geoscience Australia and Monash University, it represents a novel approach to model multiple interconnected resource facilities. Following the Economic Fairways approach, the Mapper combines large-scale infrastructure and geoscience datasets to provide a high-level, geospatial analysis of the economic viability of hypothetical green steel projects. In doing so it creates a new capability within Australia—filling the void before the detail and expense of feasibility studies—to understand the broad contours of the decarbonization challenge, and to inform early-stage decision making in the pursuit of low-carbon steel. In this seminar, we introduce the Green Steel Economic Fairways Mapper, demonstrate its capabilities, and discuss some of the insights it reveals.&nbsp;</div>

<div>Geoscience Australia's collaborative Antarctic Geoscience program provides scientific and strategic leadership on key national priorities in Antarctica and the Southern Ocean.&nbsp;&nbsp;</div><div>From February to April 2024 one of our scientists participated in an international marine expedition to the East Antarctic Ice Shelf along Australia's Antarctic Territory coast. The expedition aboard the Research Vessel <em>Polarstern</em> entitled "East Antarctic Ice Sheet Instability and its interaction with changes in Southern Ocean circulation - Part 3" (EASI-3), was the third of the EASI expeditions to investigate ocean–ice sheet interactions along the East Antarctic margin.&nbsp;</div><div><br></div><div>This talk presents the voyage highlights, including scientific exploration, seabed mapping, sonars, sediment sampling, ship life and wildlife, by inviting the audience into the world of an Antarctic expeditioner.&nbsp;</div><div><br></div>

<div>As a planet without plate tectonics, Mars has a fundamentally different setting to Earth, and yet we observe many familiar structural features at the surface. Mars is also home to the largest volcanoes in the Solar System, which are the spectacular surface expressions of an enormous, long-lived magmatic system underlying the region known as Tharsis. The many surface structures in the Tharsis region are an important record of the geologic and volcanic history of Mars. They can provide insight into the timing and nature of volcanic systems, which is important to investigations of past climate and potential habitability. This talk will explore how volcanism has driven formation of the structures we see on the surface of Mars and how this can help us answer important questions about the evolution of the red planet. The work presented is based on Dr Claire Orlov's PhD research conducted at the University of Leeds, UK. </div>

<div>This presentation is about the National Hydrogeological Inventory, developed as part of Geoscience Australia's national-scale groundwater research efforts in the Exploring for the Future (EFTF) program. The presentation is part of the 2024 Distinguished Geoscience Australia Lecture (DGAL) series.</div><div><br></div><div>One of Geoscience Australia's strategic drivers is to Improve understanding of Australia's groundwater systems to support sustainable management and help to secure our water resources to optimise and sustain their use. Aligned with this key objective, and as part of the EFTF program, Geoscience Australia developed and delivered the first comprehensive update to the Hydrogeology of Australia map and supporting report since first published more than 35 years ago.</div><div>&nbsp;</div><div>Known as the National Hydrogeological Inventory (NHI), this new online mapping application delivers consistent national-scale synthesis of hydrogeological and related data and information for the nation's 42 major groundwater provinces. Accessible via the Geoscience Australia Data Discovery Portal, the NHI provides an enhanced and updated picture of groundwater systems across Australia, giving us a broader understanding of the communities, industries, and environments that rely on access to groundwater. This presentation uncovers the story behind the development of the inventory, looking at why it was developed, the type of information it contains, and plans for further improvements as part of the new Resourcing Australia's Prosperity Initiative.</div><div> </div>

<div>GNSS, one of which is the more familiar US Global Positioning System (GPS), have become part of our everyday life… in our cars, phones and even smartwatches – helping us know where we are and where we want to go. Join me to explore advances in the analysis of GNSS in an Australia context.</div><div>Knowing our ‘place in space’ is an inherent human emotive connection and Global Navigation Satellite Systems (GNSS), as a technology, has become prevalent in the world around us, and as a society we have become reliant on basic functions such as knowing where we are, and how to navigate from one place to another.</div><div>Advances in analysis of GNSS observations has led to us being able to determine a location down to the sub-millimetre; calculate precise orbital arcs of low earth satellite platforms that are exploding in numbers for innovative communication technologies and earth observation; define how wet the troposphere is, and assist weather forecasting models; and even provide real-time precise positioning at the centimetre-level for a variety of applications.</div><div><br></div><div>This presentation will take you through advances in positioning and navigation technologies through the lens of GNSS products and services based at Geoscience Australia, and how these benefit everyday Australians.</div><div><br></div>