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  • Alkaline and related rocks are a relatively rare class of igneous rocks worldwide. Alkaline rocks encompass a wide range of rock types and are mineralogically and geochemically diverse. They are typically though to have been derived by generally small to very small degrees of partial melting of a wide range of mantle compositions. As such these rocks have the potential to convey considerable information on the evolution of the Earth’s mantle (asthenosphere and lithosphere), particularly the role of metasomatism which may have been important in their generation or to which such rocks may themselves have contributed. Such rocks, by their unique compositions and or enriched source protoliths, also have considerable metallogenic potential, e.g., diamonds, Th, U, Zr, Hf, Nb, Ta, REEs. It is evident that the geographic occurrences of many of these rock types are also important, and may relate to presence of old cratons, craton margins or major lithospheric breaks. Finally, many alkaline rocks also carry with them mantle xenoliths providing a snapshot of the lithospheric mantle composition at the time of their emplacement. Accordingly, although Alkaline and related rocks comprise only a volumetrically minor component of the geology of Australia, they are of considerable importance to studies of lithospheric composition, evolution and architecture and to helping constrain the temporal evolution of the lithosphere, as well as more directly to metallogenesis and mineralisation. This contribution presents the first part of an ongoing compilation of the distribution and geology of alkaline and related rocks throughout Australia. The report and accompanying GIS document alkaline and related rocks of Archean age. All are from the Pilbara and Yilgarn Cratons of Western Australia. The report also reviews the nomenclature of alkaline rocks and classification procedures. GIS metadata is documented in the appendices.

  • Alkaline and related rocks are a relatively rare class of igneous rocks worldwide. Alkaline rocks encompass a wide range of rock types and are mineralogically and geochemically diverse. They are typically though to have been derived by generally small to very small degrees of partial melting of a wide range of mantle compositions. As such these rocks have the potential to convey considerable information on the evolution of the Earth’s mantle (asthenosphere and lithosphere), particularly the role of metasomatism which may have been important in their generation or to which such rocks may themselves have contributed. Such rocks, by their unique compositions and or enriched source protoliths, also have considerable metallogenic potential, e.g., diamonds, Th, U, Zr, Hf, Nb, Ta, REEs. It is evident that the geographic occurrences of many of these rock types are also important, and may relate to presence of old cratons, craton margins or major lithospheric breaks. Finally, many alkaline rocks also carry with them mantle xenoliths providing a snapshot of the lithospheric mantle composition at the time of their emplacement. Accordingly, although alkaline and related rocks comprise only a volumetrically minor component of the geology of Australia, they are of considerable importance to studies of lithospheric composition, evolution and architecture and to helping constrain the temporal evolution of the lithosphere, as well as more directly to metallogenesis and mineralisation. This contribution presents data on the distribution and geology of Australian alkaline and related rocks of Mesozoic age. The report and accompanying GIS document the distribution, age, lithology, mineralogy and other characteristics of these rocks (e.g., extrusive/intrusive, presence of mantle xenoliths, presence of diamonds), as well as references for data sources and descriptions. The report also reviews the nomenclature of alkaline rocks and classification procedures. GIS metadata are documented in the appendices.

  • Alkaline and related rocks are a relatively rare class of igneous rocks worldwide. Alkaline rocks encompass a wide range of rock types and are mineralogically and geochemically diverse. They are typically though to have been derived by generally small to very small degrees of partial melting of a wide range of mantle compositions. As such these rocks have the potential to convey considerable information on the evolution of the Earth’s mantle (asthenosphere and lithosphere), particularly the role of metasomatism which may have been important in their generation or to which such rocks may themselves have contributed. Such rocks, by their unique compositions and or enriched source protoliths, also have considerable metallogenic potential, e.g., diamonds, Th, U, Zr, Hf, Nb, Ta, REEs. It is evident that the geographic occurrences of many of these rock types are also important, and may relate to presence of old cratons, craton margins or major lithospheric breaks. Finally, many alkaline rocks also carry with them mantle xenoliths providing a snapshot of the lithospheric mantle composition at the time of their emplacement. Accordingly, although Alkaline and related rocks comprise only a volumetrically minor component of the geology of Australia, they are of considerable importance to studies of lithospheric composition, evolution and architecture and to helping constrain the temporal evolution of the lithosphere, as well as more directly to metallogenesis and mineralisation. This GIS product presents the first part of an ongoing compilation of the distribution and geology of alkaline and related rocks throughout Australia. The accompanying report document alkaline and related rocks of Archean age. All are from the Pilbara and Yilgarn Cratons of Western Australia. The report also reviews the nomenclature of alkaline rocks and classification procedures. GIS metadata is documented in the appendices.

  • Australia remains underexplored or unexplored, boasting discovery potential in the mineral, groundwater, and energy resources hidden beneath the surface. These “greenfield” areas are key to Australia’s future prosperity and sustainability. Led by Geoscience Australia, Australia’s national government geoscience organisation, the Exploring for the Future program was a groundbreaking mission to map Australia’s mineral, energy, and groundwater systems in unparalleled scale and detail. The program has advanced our understanding of Australia’s untapped potential. Over the course of 8 years, the Exploring for the Future program provided a significant expansion of public, precompetitive geoscience data and information, equipping decision-makers with the knowledge and tools to tackle urgent challenges related to Australia’s resource prosperity, energy security, and groundwater supply.

  • <div>Strontium isotopes (87Sr/86Sr) are useful in the earth sciences (e.g. recognising geological provinces, studying geological processes) as well in archaeological (e.g. informing on past human migrations), palaeontological/ecological (e.g. investigating extinct and extant taxa’s dietary range and migrations) and forensic (e.g. validating the origin of drinks and foodstuffs) sciences. Recently, Geoscience Australia and the University of Wollongong have teamed up to determine 87Sr/86Sr ratios in fluvial sediments selected mostly from the low-density National Geochemical Survey of Australia (NGSA; www.ga.gov.au/ngsa). The present study targeted the Yilgarn geological region in southwestern Australia. The samples were mostly taken from a depth of ~60-80 cm (Bottom Outlet Sediments, BOS) in floodplain deposits at or near the outlet of large catchments (drainage basins). A small number of surface (0-10 cm) samples (Top Outlet Sediments, TOS) were also included in the study. For all, a coarse grain-size fraction (<2 mm) was air-dried, sieved, milled then digested (hydrofluoric acid + nitric acid followed by aqua regia) to release total strontium. Overall, 107 NGSA BOS < 2 mm and 13 NGSA TOS < 2 mm were analysed for Sr isotopes. Given that there are ~10 % field duplicates in the NGSA, all those samples originate from within 97 NGSA catchments, which together cover 533 000 km2 of southwestern Australia. Preliminary results for the BOS samples demonstrate a wide range of strontium isotopic values (0.7152 < 87Sr/86Sr < 1.0909) over the survey area, reflecting a large diversity of source rock lithologies, geological processes and bedrock ages. Spatial distribution of 87Sr/86Sr shows coherent (multi-point anomalies and smooth gradients), large-scale (>100 km) patterns that appear to be consistent, in many places, with surface geology, regolith/soil type and/or nearby outcropping bedrock. For instance, catchments in the western and central Yilgarn dominated by felsic intrusive basement geology have radiogenic 87Sr/86Sr signatures in the floodplain sediments consistent with published whole-rock data. Similarly, unradiogenic signatures in sediments in the eastern Yilgarn are in agreement with published whole-rock data. Our results to-date indicate that incorporating soil/regolith strontium isotopes in regional, exploratory geoscience investigations can help identify basement rock types under (shallow) cover, constrain surface processes (e.g. weathering, dispersion), and, potentially, recognise components of mineral systems. Furthermore, the resulting strontium isoscape and model derived therefrom can also be utilised in archaeological, paleontological and ecological studies that aim to investigate past and modern animal (including humans) dietary habits and migrations.&nbsp; The new spatial dataset is publicly available through the Geoscience Australia portal https://portal.ga.gov.au/.</div>

  • <div>This Record documents the efforts of Geoscience Australia (GA) in compiling a New South Wales (NSW) Uranium–Lead (U–Pb) geochronology interpreted age compilation (version 1.0), utilising the MinView data from the Geological Survey of New South Wales (GSNSW), GA’s ‘in house’ storage of SHRIMP (Sensitive High Resolution Ion Micro Probe) ages, and other disparate publication sources e.g. academic journal articles and university theses. Here we describe both the dataset itself and the process by which it is incorporated into the continental-scale Isotopic Atlas of Australia. This initial release of the NSW geochronology compilation comprises of 1007 U–Pb ages of named and unnamed rock units in NSW.&nbsp;</div><div><br></div><div>The Isotopic Atlas draws together age and isotopic data from across the country and provides visualisations and tools to enable non-experts to extract maximum value from these datasets. Data is added to the Isotopic Atlas in a staged approach with priorities determined by GA- and partner-driven focus regions and research questions. This NSW U–Pb compilation represents the third in a series of compilation publications (Records and Datasets) for the southern states of Australia, which are a foundation for the second phase of the Exploring for the Future initiative over the period 2020–2024. All geochronology compilations in this series of Isotopic Atlas of Australia Records are available online from the Geochronology and Isotopes Data Portal.</div><div><br></div>

  • The Exploring for the Future program Showcase 2024 was held on 13-16 August 2024. Day 3 - 15th August talks included: <b>Session 1 – Hydrogen opportunities across Australia</b> <a href="https://youtu.be/pA9ft3-7BtU?si=V0-ccAmHHIYJIZAo">Hydrogen storage opportunities and the role of depleted gas fields</a> - Dr Eric Tenthorey <a href="https://youtu.be/MJFhP57nnd0?si=ECO7OFTCak78Gn1M">The Green Steel Economic Fairways Mapper</a> - Dr Marcus Haynes <a href="https://youtu.be/M95FOQMRC7o?si=FyP7CuDEL0HEdzPw">Natural hydrogen: The Australian context</a> - Chris Boreham <b>Session 2 – Sedimentary basin resource potential – source rocks, carbon capture and storage (CCS) and groundwater</b> <a href="https://youtu.be/44qPlV7h3os?si=wfQqxQ81Obhc_ThE">Australian Source Rock and Fluid Atlas - Accessible visions built on historical data archives</a> - Dr Dianne Edwards <a href="https://youtu.be/WcJdSzsADV8?si=aH5aYbpnjaz3Qwj9">CO2: Where can we put it and how much will it cost?</a> - Claire Patterson <a href="https://youtu.be/Y8sA-iR86c8?si=CUsERoEkNDvIwMtc">National aquifer framework: Putting the geology into hydrogeology</a> - Dr Nadege Rollet <b>Session 3 – Towards a national inventory of resource potential and sustainable development</b> <a href="https://youtu.be/K5xGpwaIWgg?si=2s0AKuNpu30sV1Pu">Towards a national inventory of mineral potential</a> - Dr Arianne Ford <a href="https://youtu.be/XKmEXwQzbZ0?si=yAMQMjsNCGkAQUMh">Towards an inventory of mine waste potential</a> - Dr Anita Parbhakar-Fox <a href="https://youtu.be/0AleUvr2F78?si=zS4xEsUYtARywB1j">ESG mapping of the Australian mining sector: A critical review of spatial datasets for decision making</a> - Dr Eleonore Lebre 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 3 - Session 1 - <a href="https://www.youtube.com/watch?v=Ho6QFMIleuE">Hydrogen opportunities across Australia</a> 2024 Showcase Day 3 - Session 2 - <a href="https://www.youtube.com/watch?v=ePZfgEwo0m4">Sedimentary basin resource potential – source rocks, carbon capture and storage (CCS) and groundwater</a> 2024 Showcase Day 3 - Session 3 - <a href="https://www.youtube.com/watch?v=CjsZVK4h6Dk">Towards a national inventory of resource potential and sustainable development</a>

  • The Exploring for the Future program Showcase 2024 was held on 13-16 August 2024. Day 2 - 14th August talks included: <b>Session 1 - Architecture of the Australian Tectonic Plate</b> <a href="https://youtu.be/a8jzTdNdwfk?si=OWNlVR-FLDhF1GVM">AusArray: Australian lithosphere imaging from top to bottom</a> - Dr Alexei Gorbatov <a href="https://youtu.be/j5ox8Ke5n6M?si=YkfDno2xmZXueS1b">AusLAMP: Mapping lithospheric architecture and reducing exploration space in Australia</a> - Jingming Duan <a href="https://youtu.be/qZ6wjzx_dNc?si=NjDEzvqyEeM24-E8">Constraining the thermomechanical and geochemical architecture of the Australian mantle: Using combined analyses of xenolith inventories and seismic tomography</a> - Dr Mark Hoggard <b>Session 2 - Quantitative characterisation of Australia's surface and near surface</b> <a href="https://youtu.be/nPfa_j3_dos?si=mktfIJWXeLElIOK4">AusAEM: The national coverage and sharpening near surface imaging</a> - Dr Anandaroop Ray <a href="https://youtu.be/SU6ak98JvAw?si=DQPovulHa4poqcm0">Unlocking the surface geochemistry of Australia</a> - Phil Main <a href="https://youtu.be/Xtm45CT6e-s?si=JHU7J-ktgVrbj1Ke">Spotlight on the Heavy Mineral Map of Australia</a> - Dr Alex Walker <b>Session 3 – Maps of Australian geology like never before</b> <a href="https://youtu.be/aRISb1YYigU?si=3byJbqW0qRTqCB8-">An Isotopic Atlas of Australia: Extra dimensions to national maps</a> - Dr Geoff Fraser <a href="https://youtu.be/khSy-WAkw-w?si=F-Y67FX3jXN5zZaz">First continental layered geological map of Australia</a> - Dr Guillaume Sanchez <a href="https://youtu.be/Z3GlCJepLK4?si=k_tbaKdmxGBmoSro">An integrated 3D layered cover modelling approach: Towards open-source data and methodologies for national-scale cover modelling</a> - Sebastian Wong 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 2 - Session 1 - <a href="https://www.youtube.com/watch?v=EHBsq0-pC8c">Architecture of the Australian Tectonic Plate</a> 2024 Showcase Day 2 - Session 2 - <a href="https://youtube.com/watch?v=xih4lbDk-1A">Quantitative characterisation of Australia's surface and near surface</a> 2024 Showcase Day 2 - Session 3 - <a href="https://www.youtube.com/watch?v=qeTLc1K-Cds">Maps of Australian geology like never before</a>

  • Alkaline and related rocks are a relatively rare class of igneous rocks worldwide. Alkaline rocks encompass a wide range of rock types and are mineralogically and geochemically diverse. They are typically though to have been derived by generally small to very small degrees of partial melting of a wide range of mantle compositions. As such these rocks have the potential to convey considerable information on the evolution of the Earth’s mantle (asthenosphere and lithosphere), particularly the role of metasomatism which may have been important in their generation or to which such rocks may themselves have contributed. Such rocks, by their unique compositions and or enriched source protoliths, also have considerable metallogenic potential, e.g., diamonds, Th, U, Zr, Hf, Nb, Ta, REEs. It is evident that the geographic occurrences of many of these rock types are also important, and may relate to presence of old cratons, craton margins or major lithospheric breaks. Finally, many alkaline rocks also carry with them mantle xenoliths providing a snapshot of the lithospheric mantle composition at the time of their emplacement. Accordingly, although Alkaline and related rocks comprise only a volumetrically minor component of the geology of Australia, they are of considerable importance to studies of lithospheric composition, evolution and architecture and to helping constrain the temporal evolution of the lithosphere, as well as more directly to metallogenesis and mineralisation. This GIS product is part of an ongoing compilation of the distribution and geology of alkaline and related rocks throughout Australia. The accompanying report document alkaline and related rocks of Mesozoic age.

  • <div>Alkaline and related rocks are a relatively rare class of igneous rocks worldwide. Alkaline rocks encompass a wide range of rock types and are mineralogically and geochemically diverse. They are typically though to have been derived by generally small to very small degrees of partial melting of a wide range of mantle compositions. As such these rocks have the potential to convey considerable information on the evolution of the Earth’s mantle (asthenosphere and lithosphere), particularly the role of metasomatism which may have been important in their generation or to which such rocks may themselves have contributed. Such rocks, by their unique compositions and or enriched source protoliths, also have considerable metallogenic potential, e.g., diamonds, Th, U, Zr, Hf, Nb, Ta, REEs. It is evident that the geographic occurrences of many of these rock types are also important, and may relate to presence of old cratons, craton margins or major lithospheric breaks. Finally, many alkaline rocks also carry with them mantle xenoliths providing a snapshot of the lithospheric mantle composition at the time of their emplacement.</div><div><br></div><div>Accordingly, although Alkaline and related rocks comprise only a volumetrically minor component of the geology of Australia, they are of considerable importance to studies of lithospheric composition, evolution and architecture and to helping constrain the temporal evolution of the lithosphere, as well as more directly to metallogenesis and mineralisation.</div><div><br></div><div>This GIS product is part of an ongoing compilation of the distribution and geology of alkaline and related rocks throughout Australia. The accompanying report document alkaline and related rocks of Cenozoic age.</div>