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  • <p>Understanding the geological evolution and resource prospectivity of a region relies heavily on the integration of different geological and geophysical datasets. Geochronology is one key dataset, as it underpins meaningful geological correlations across large regions, and also contributes to reconstruction of past tectonic settings. Using geochronology in combination with other datasets requires the geochronology data to be available in a unified dataset with a consistent format. Northern Australia is a vast and relatively underexplored area that offers enormous potential for the discovery of mineral and energy resources. The area has a long and variably complex tectonic history, which is yet to be fully understood. Numerous geochronology studies have been completed at various scales throughout northern Australia over several decades; however, these data are scattered amongst numerous sources, limiting the ease with which they can be used collectively. <p>The objective of this work is: <p>(1) to combine Uranium–Lead (U–Pb) data across north-northeastern Australia into one consistent dataset, and <p>(2) to visualise the temporal and spatial distribution of the U–Pb age data through thematic maps as a tool for better understanding the geological evolution and resource potential of northern Australia. <p>In this contribution, over 2000 U–Pb ages from the Northern Territory, Queensland, eastern Western Australia and northern South Australia have been compiled into a single, consistent dataset. Data were sourced from Geoscience Australia, State and Territory geological surveys and from academic literature. The compilation presented here includes age data from igneous, metamorphic and sedimentary rocks. Thematic maps of magmatic crystallisation ages, high-grade metamorphic ages and sedimentary maximum depositional ages have been generated using the dataset. These maps enable spatial and temporal trends in the rock record to be visualised up to semi-continental scale and form a component of the ‘Isotopic Atlas’ of northern Australia currently being compiled by Geoscience Australia.

  • The Exploring for the Future Project Areas web service depicts the spatial extents of project work undertaken as part of Geoscience Australia's $100.5 million initiative dedicated to boosting investment in resource exploration in Australia. Each project area extent has been generated by aggregating all project work sites into an envelope polygon. An indicative spend on each f the projects is also given.

  • Newer version v1.1 available at eCat <a href="https://pid.geoscience.gov.au/dataset/ga/147720">147720</a> Isotopic data from rocks and minerals have the potential to yield unique insights into the composition and evolution of the Earth's crust and mantle. Time-integrated records of crust and mantle differentiation (as preserved by the U-Pb, Sm-Nd and Lu-Hf isotopic systems, for example) are important in a wide range of geological applications, especially when successfully integrated with other geological, geophysical, and geochemical datasets. However, such integration requires (i) compilation of comprehensive isotopic data coverages, (ii) unification of datasets in a consistent structure to facilitate inter-comparison, and (iii) easy public accessibility of the compiled and unified datasets in spatial and tabular formats useful and useable by a broad range of industry, government and academic users. This constitutes a considerable challenge, because although a wealth of isotopic information has been collected from the Australian continent over the last 40 years, the published record is fragmentary, and derived from numerous and disparate sources. Unlocking and harnessing the collective value of isotopic datasets will enable more comprehensive and powerful interpretations, and significantly broaden their applicability to Earth evolution studies and mineral exploration. As part of the Exploring for the Future (EFTF) program (https://www.ga.gov.au/eftf), we have designed a new database structure and web service system to store and deliver full Lu-Hf isotope and associated O-isotope datasets, spanning new data collected during research programs conducted by Geoscience Australia (GA), as well as compiled literature data. Our approach emphasises the links between isotopic measurements and their spatial, geological, and data provenance information in order to support the widest possible range of uses. In particular, we build and store comprehensive links to the original sources of isotopic data so that (i) users can easily track down additional context and interpretation of datasets, and (ii) generators of isotopic data are appropriately acknowledged for their contributions. This system delivers complete datasets including (i) full analytical and derived data as published by the original author, (ii) additional, normalised derived data recalculated specifically to maximise inter-comparability of data from disparate sources, (iii) metadata related to the analytical setup, (iv) a broad range of sample information including sampling location, rock type, geological province and stratigraphic unit information, and (v) descriptions of (and links to) source publications. The data is delivered through the Geoscience Australia web portal (www.portal.ga.gov.au), and can also be accessed through any web portal capable of consuming Open Geospatial Consortium (OGC)-compliant web services, or any GIS system capable of consuming Web Map Services (WMS) or Web Feature Services (WFS). This Record describes the database system and web service tables. It also contains full tabulated datasets for data compiled from the North Australian Craton as part of the EFTF program. These data are predominantly micro-analytical zircon analyses which are linked at the spot-level across Lu-Hf, O, and U-Pb measurements. This data release comprises 5974 individual analyses from 149 unique rock samples.

  • Digital Earth Australia (DEA) is a key piece of public data infrastructure that uses images and information recorded by satellites orbiting our planet to detect physical changes across Australia in unprecedented detail. Landsat 5, 7 and 8 ‘analysis-ready’ data are currently available within DEA, where the raw satellite data have been corrected and orthorectified to enable easy interrogation of data across sensors. Geoscience Australia is developing techniques for analysing the data within DEA to identify wetlands and groundwater dependent ecosystems across northern Australia. These techniques include summarising observations of ‘wetness’ acquired over 30 years and linking these observations to gridded rainfall measurements to identity waterbodies and wetlands that persist during periods of low rainfall. These wetness summaries have been shown to correspond with known spring complexes in the Carmichael River catchment in Queensland, and have been used to improve the understanding of groundwater discharge processes within basalt provinces in the Upper Burdekin region in Queensland. This poster was submitted/presented to the 2018 Australian Geoscience Council Convention (AGCC) 14-18 October (https://www.agcc.org.au/)

  • The AusAEM1 survey is the world’s largest airborne electromagnetic survey flown to date, extending across an area exceeding 1.1 million km2 over Queensland and the Northern Territory. Approximately 60 000 line kilometres of data were acquired at a nominal line spacing of 20 km. Using this dataset, we interpreted the depth to chronostratigraphic surfaces, assembled stratigraphic relationship information, and delineated structural and electrically conductive features. Our results improved understanding of upper-crustal geology, led to 3D mapping of palaeovalleys, prompted further investigation of electrical conductors and their relationship to structural features and mineralisation, and helped us continuously connect correlative outcropping units separated by up to hundreds of kilometres. Our interpretation is designed to improve targeting and outcomes for mineral, energy and groundwater exploration, and contributes to our understanding of the chronostratigraphic, structural and upper-crustal evolution of northern Australia. More than 150 000 regional depth measurements, each attributed with detailed geological information, are an important step towards a national geological framework, and offer a regional context for more detailed, smaller-scale AEM surveys. <b>Citation:</b> Wong, S.C.T., Roach, I.C., Nicoll, M.G., English, P.M., Bonnardot, M.-A., Brodie, R.C., Rollet, N. and Ley-Cooper, A.Y., 2020. Interpretation of the AusAEM1: insights from the world’s largest airborne electromagnetic survey. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

  • The South Nicholson region, which includes the Paleoproterozoic Isa Superbasin, the Mesoproterozoic South Nicholson Group and overlying younger sediments, is sparsely explored and has recently come into increased focus as a result of the Australian Government’s Exploring for the Future program. Previous exploration has identified potential shale gas plays within the River and Lawn supersequences of the Isa Superbasin in northwest Queensland’s northern Lawn Hill Platform region. Understanding mineralogy is important for characterising shale reservoirs, as mechanical properties such as shale brittleness are influenced by mineral composition. Mineralogy can, therefore, be utilised as a proxy for mechanical properties that are crucial to minimising risks associated with exploring for and developing shale reservoirs. This study utilises three different methods for calculating brittleness; XRD mineralogy, XRF major element geochemistry, and geomechanical properties. Results indicate highly variable mineralogy within the analysed samples, demonstrating heterogeneity in shale brittleness throughout the studied supersequences. Brittleness calculated from XRD analysis ranges from ductile to brittle with zones of brittle shales present in all supersequences. Increasing quartz and decreasing clay content is the dominant control on shale brittleness in the studied samples. Correlation between XRF major element geochemistry and XRD mineralogy is demonstrated to be moderate to poor, with brittleness derived from XRF major element geochemistry observed to be significantly higher than brittleness derived from XRD mineralogy. Conversely, brittleness derived from geomechanical properties agrees closely with XRD mineralogy derived brittleness. Hence, XRF major element geochemistry data are not recommended in the South Nicholson region to calculate brittleness. Analysis of brittleness indices from this study, in combination with total organic carbon content drawn from regional geochemical analysis in the South Nicholson region, identifies potential shale gas target intervals in the River, Term, and Lawn supersequences. Data presented on correlated well sections highlights intervals of exploration interest within these supersequences, being those depths where high organic content, brittle rocks are identified. The rocks that meet this criteria are primarily constrained to the already known potential shale gas plays of the River and Lawn supersequences. Recent data from Geoscience Australia implies that these potential shale gas plays are likely to extend from the northern Lawn Hill Platform, where they have been primarily identified to date, underneath the South Nicholson Basin and into the Carrara Sub-basin, significantly increasing their lateral extent. <b>Citation:</b> A. H. E. Bailey, A. J. M. Jarrett, L. Wang, B. L. Reno, E. Tenthorey, C. Carson & P. Henson (2022) Shale brittleness within the Paleoproterozoic Isa Superbasin succession in the South Nicholson region, Northern Australia, <i>Australian Journal of Earth Sciences, </i>DOI: 10.1080/08120099.2022.2095029

  • Developing Northern Australia Map produced on request for the Office of Northern Australia. It highlights development in northern Australia, indicating major mineral and energy resource projects, mineral deposits, and major infrastructure. It also incorporates data from other Government agencies, providing key information used to inform decision makers in the region such as environmental data, location of indigenous communities, native title determinations, and indigenous land use agreements.

  • The AusAEM1 airborne electromagnetic survey extends across an area exceeding 1.1 million km2 over Queensland and the Northern Territory. Approximately 60,000 line kilometres of data were acquired at a nominal line spacing of 20 km (Ley-Cooper et al., 2020). To improve targeting and outcomes for mineral, energy and groundwater exploration, we conducted a regional interpretation of this dataset to characterise the subsurface geology of northern Australia. The interpretation includes the depth to chronostratigraphic surfaces, compilation of stratigraphic relationship information, and delineation of structural and electrically conductive features. In addition to help connecting correlative outcropping units separated by up to hundreds of kilometres, the results led to 3D mapping of palaeovalleys and prompted further investigation of electrical conductors and their relationship to structural features and mineralisation. Approximately 200,000 regional depth point measurements, each attributed with detailed geological information, are an important step towards a national geological framework, and offer a regional context for more detailed, smaller-scale AEM surveys. Refer to Wong et al., (2020) for more details on the AusAEM1 interpretation.

  • The Exploring for the Future Project Areas web service depicts the spatial extents of project work undertaken as part of Geoscience Australia's $100.5 million initiative dedicated to boosting investment in resource exploration in Australia. Each project area extent has been generated by aggregating all project work sites into an envelope polygon. An indicative spend on each f the projects is also given.

  • Long-period magnetotelluric (MT) data allow geoscientists to investigate the link between mineralisation and lithospheric-scale features and processes. In particular, the highly conductive structures imaged by MT data appear to map the pathways of large-scale palaeo-fluid migration, the identification of which is an important element of several mineral system models. Given the importance of these data, governments and academia have united under the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) to collect long-period MT data across the continent on a ~55 km-spaced grid. Here, we use AusLAMP data to demonstrate the MT method as a regional-scale tool to identify and select prospective areas for mineral exploration undercover. We focus on the region between Tennant Creek in the Northern Territory and east of Mount Isa in Queensland. Our results image major conductive structures up to 150 km deep in the lithosphere, such as the Carpentaria Conductivity Anomaly east of Mount Isa. This anomaly is a significant lithospheric-scale conductivity structure that shows spatial correlations with a major suture zone and known iron oxide–copper–gold deposits. Our results also identify similar features in several under-explored areas that are now considered to be prospective for mineral discovery. These observations provide a powerful means of selecting frontier regions for mineral exploration undercover.. <b>Citation:</b> Duan, J., Kyi, D., Jiang, W. and Costelloe, M., 2020. AusLAMP: imaging the Australian lithosphere for resource potential, an example from northern Australia. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.