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  • Australia has been, and continues to be, a leader in isotope geochronology and geochemistry. While new isotopic data is being produced with ever increasing pace and diversity, there is also a rich legacy of existing high-quality age and isotopic data, most of which have been dispersed across a multitude of journal papers, reports and theses. Where compilations of isotopic data exist, they tend to have been undertaken at variable geographic scale, with variable purpose, format, styles, levels of detail and completeness. Consequently, it has been difficult to visualise or interrogate the collective value of age and isotopic data at continental-scale. Age and isotopic patterns at continental scale can provide intriguing insights into the temporal and chemical evolution of the continent (Fraser et al, 2020). As national custodian of geoscience data, Geoscience Australia has addressed this challenge by developing an Isotopic Atlas of Australia, which currently (as of November 2020) consists of national-scale coverages of four widely-used age and isotopic data-types: 4008 U-Pb mineral ages from magmatic, metamorphic and sedimentary rocks 2651 Sm-Nd whole-rock analyses, primarily of granites and felsic volcanics 5696 Lu-Hf (136 samples) and 553 O-isotope (24 samples) analyses of zircon 1522 Pb-Pb analyses of ores and ore-related minerals These isotopic coverages are now freely available as web-services for use and download from the GA Portal. While there is more legacy data to be added, and a never-ending stream of new data constantly emerging, the provision of these national coverages with consistent classification and attribution provides a range of benefits: vastly reduces duplication of effort in compiling bespoke datasets for specific regions or use-cases data density is sufficient to reveal meaningful temporal and spatial patterns a guide to the existence and source of data in areas of interest, and of major data gaps to be addressed in future work facilitates production of thematic maps from subsets of data. For example, a magmatic age map, or K-Ar mica cooling age map sample metadata such as lithology and stratigraphic unit is associated with each isotopic result, allowing for further filtering, subsetting and interpretation. The Isotopic Atlas of Australia will continue to develop via the addition of both new and legacy data to existing coverages, and by the addition of new data coverages from a wider range of isotopic systems and a wider range of geological sample media (e.g. soil, regolith and groundwater).

  • This Record presents data collected as part of the ongoing NTGS-GA geochronology project between July 2014 and June 2015 under the National Collaborative Framework (NCF). In total, five new U-Pb SHRIMP zircon and titanite geochronological results derived from four samples from the Arunta Region in the Northern Territory are presented herein (Table 1; Figure 1). Three samples were collected from JERVOIS RANGE in HUCKITTA1 in the eastern Arunta Region, and comprise metasedimentary and metaigneous rocks. The fourth sample analysed is an igneous rock from drillcore in TOBERMOREY.

  • Take a journey through time! This app will guide you along the Geoscience Australia TimeWalk, leading you on a 1.1 kilometre journey through the Earth's 4600 million year (Ma) history. The TimeWalk is a physical representation of the evolution of the Earth from its formation to the present day. Large rock samples collected from around Australia are on display along the TimeWalk, at designated locations that reflect their age of formation. Each rock has a story to tell, with geological, economic, environmental and/or cultural significance. Use this app to read, hear and learn all about the significance of these rocks and their relevance to Earth's history. Plus, discover other facts and events of geological history along the way! The TimeWalk is located in the landscaped gardens at the front of the Geoscience Australia building, at the corner of Jerrabomberra Ave and Hindmarsh Drive, Canberra, Australia. Record removed from external publication 26 November 2021. App has been disabled on the App store as it doesn't currently work. https://itunes.apple.com/us/app/geoscience-australia-time/id899855813?ls=1&mt=8

  • The fundamental geological framework of the concealed Paleoproterozoic East Tennant area of northern Australia is very poorly understood, despite its relatively thin veneer of Phanerozoic cover and its position along strike from significant Au–Cu–Bi mineralisation of the Tennant Creek mining district within the outcropping Warramunga Province. We present 18 new U–Pb dates, obtained via Sensitive High Resolution Ion Micro Probe (SHRIMP), constraining the geological evolution of predominantly Paleoproterozoic metasedimentary and igneous rocks intersected by 10 stratigraphic holes drilled in the East Tennant area. The oldest rocks identified in the East Tennant area are two metasedimentary units with maximum depositional ages of ca. 1970 Ma and ca. 1895 Ma respectively, plus ca. 1870 Ma metagranitic gneiss. These units, which are unknown in the nearby Murphy Province and outcropping Warramunga Province, underlie widespread metasedimentary rocks of the Alroy Formation, which yield maximum depositional ages of 1873–1864 Ma. While parts of this unit appear to be correlative with the ca. 1860 Ma Warramunga Formation of the Warramunga Province, our data suggest that the bulk of the Alroy Formation in the East Tennant area is slightly older, reflecting widespread sedimentation at ca. 1870 Ma. Throughout the East Tennant area, the Alroy Formation was intruded by voluminous 1854–1845 Ma granites, contemporaneous with similar felsic magmatism in the outcropping Warramunga Province (Tennant Creek Supersuite) and Murphy Province (Nicholson Granite Complex). In contrast with the outcropping Warramunga Province, supracrustal rocks equivalent to the 1845–1810 Ma Ooradidgee Group are rare in the East Tennant area. Detrital zircon data from younger sedimentary successions corroborate seismic evidence that at least some of the thick sedimentary sequences intersected along the southern margin of the recently defined Brunette Downs rift corridor are possible age equivalents of the ca. 1670–1600 Ma Isa Superbasin. Our new results strengthen ca. 1870–1860 Ma stratigraphic and ca. 1850 Ma tectono-magmatic affinities between the East Tennant area, the Murphy Province, and the mineralised Warramunga Province around Tennant Creek, with important implications for mineral prospectivity of the East Tennant area. Appeared in Precambrian Research Volume 383, December 2022.

  • To test existing geological interpretations and the regional stratigraphic relationships of the Carrara Sub-basin with adjacent resource-rich provinces, the deep stratigraphic drill hole NDI Carrara 1 was located on the western flanks of the Carrara Sub-basin, on the seismic line 17GA-SN1. The recovery of high quality near-continuous core from the Carrara Sub-basin, in concert with the spectrum of baseline analytical work being conducted by Geoscience Australia through the EFTF program, as well as other work by government and university researchers is greatly improving our understanding of this new basin. While recently published geochemistry baseline datasets have provided valuable insight into the Carrara Sub-basin, the age of the sedimentary rocks intersected by NDI Carrara 1 and their chronostratigraphic relationships with adjacent resource rich regions has remained an outstanding question. In this contribution, we present new sensitive high-resolution ion microprobe (SHRIMP) geochronology results from NDI Carrara 1 and establish regional stratigraphic correlations to better understand the energy and base-metal resource potential of this exciting frontier basin in northern Australia.

  • This Record contains new zircon U-Pb geochronological data obtained via Sensitive High-Resolution Ion Micro Probe (SHRIMP) from 15 samples of volcanic and plutonic igneous rocks of the Lachlan Orogen, the Thomson Orogen, and the Delamerian Orogen, New South Wales. These data were obtained during the reporting period July 2009-June 2010, under the auspices of the collaborative Geochronology Project between the Geological Survey of New South Wales (GSNSW) and Geoscience Australia (GA), which is part of the National Geoscience Accord.

  • This Record documents the efforts of the Geological Survey of Victoria (GSV) and Geoscience Australia (GA) in compiling a geochronology (age) compilation for Victoria, describing both the dataset itself and the process by which it is incorporated into the continental-scale Isotopic Atlas of Australia. 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 dataset, which was primarily compiled by GSV and has been supplemented with data compiled by GA during the 2013–2017 Stavely Project, is a foundation for the second phase of the Exploring for the Future initiative over 2020–2024, particularly the Darling-Curnamona-Delamerian Project.

  • This Record presents data collected in April 2019 as part of the ongoing Northern Territory Geological Survey–Geoscience Australia (NTGS–GA) SHRIMP geochronology project under the National Collaborative Framework (NCF) agreement and Geoscience Australia's Exploring for the Future Program. Two new U–Pb SHRIMP zircon geochronological results derived from two samples of meta-igneous and metasedimentary rocks from the Aileron and Irindina provinces in JINKA and DNEIPER (HUCKITTA) in the Northern Territory are presented herein. <b>Bibliographic Reference:</b> Kositcin N, and Reno BL, 2020. Summary of results. Joint NTGS–GA geochronology project: Aileron and Irindina provinces, Jinka and Dneiper 1:100 000 mapsheets, 2019. <i>Northern Territory Geological Survey</i>, <b>Record 2020-001</b>.

  • Geoscience Australia has compiled U-Pb datasets from disparate sources into a single, standardised and publicly-available U–Pb geochronology compilation for all Australia. The national maps presented in this poster expand upon the data coverage previously compiled by Anderson et al. (2017) and Jones et al. (2018), which covered northern and western Australia only. This extension of a national coverage has been achieved through the development of Geoscience Australia’s Interpreted Ages database. In this database, there are now >4000 U–Pb sample points compiled from across Australia, with significant datasets to come from the southern Australia regions. These will be available to the public in the coming months through the Exploring for the Future Data Discovery Portal (eftf.ga.gov.au).

  • In this Record new U-Pb SHRIMP zircon results are presented from nine samples from western South Australia and eastern Western Australia. This geochronological study was undertaken to provide temporal constraints on the crystalline basement geology beneath the Nullarbor Plain, to assist in geological interpretation of a reflection seismic transect (13GA-EG1) between the Albany-Fraser Province in the west and the central Gawler Craton in the east. This seismic line transects a region in which the crystalline basement geology is entirely buried beneath Neoproterozoic to Cenozoic sedimentary rocks. Consequently, the age, tectonic evolution and mineral potential of the crystalline basement in this region is very poorly understood. The new results complement the very limited pre-existing geochronology data from the Coompana Province and Madura Province, and provide a basis for comparison of geological ages in these provinces with the geological histories reconstructed for the adjacent provinces of the Gawler Craton to the east and the Albany-Fraser Province to the west.