<div>At the 2021 AESC (Australian Earth Sciences Convention), Geoscience Australia (GA) introduced a continental-scale Isotopic Atlas of Australia (Fraser et al., 2020) through an interactive poster display (Fraser et al., 2021). In the two years since, progress on this Isotopic Atlas has continued and expanded datasets are now publicly available and downloadable via Geoscience Australia’s Exploring for the Future (EFTF) Geochronology and Isotopes Data Portal.</div><div><br></div><div>This poster provides example maps produced from the compiled data of multiple geochronology and isotopic tracer datasets, now available in the Geochronology and Isotopes Data Portal. Available data include Sm–Nd model ages of magmatic rocks (Champion et al., 2013); Lu–Hf isotopes from zircon and associated O-isotope data (Waltenberg et al., 2023); Pb–Pb isotopes from ore-related minerals such as galena and pyrite (Huston et al., 2019); Rb–Sr stable isotopes from surface regolith (de Caritat et al., 2022, 2023); U–Pb interpreted ages of magmatic, metamorphic and sedimentary rocks (Jones et al., 2018); and K–Ar, Ar–Ar, Re–Os, Rb–Sr and fission-track interpreted ages from minerals and whole rocks.</div><div><br></div><div>Significant recent additions to the datasets include geochronology compilations for Victoria (Waltenberg et al., 2021) and Tasmania (Jones et al., 2022) and full geochronology analytical data tables for GA’s SHRIMP (Sensitive High Resolution Ion Micro Probe) U–Pb results. The online data portal provides tools for visualizing data in commonly-used diagrammatic formats (e.g. Time-Space style plots for geochronology, isotope evolution diagrams for Nd and Hf data). Data are also available for download in a range of formats (CSV, JSON, KML, Shapefile) to allow manipulation and visualization offline for specific purposes.</div><div><br></div><div>Work is ongoing to improve the coverage of legacy interpreted ages geochronology data, to include geochronology analytical data tables for both ID-TIMS and LA-ICP-MS data, and to update the Sm-Nd and Pb-Pb in ores coverages with new data. New work is in progress to develop a Pb-Pb isotopic coverage from representative ‘basement’ rocks (Liebmann et al., 2022) and to expand the coverage of oxygen and Lu-Hf isotopes from zircon, with a current focus in south-eastern Australia (Mole et al., 2022).</div><div><br></div><div>This Isotopic Atlas of Australia provides a convenient visual overview of age and isotopic patterns reflecting geological processes that have led to the current configuration of the Australian continent, including progressive development of continental crust from the mantle. These datasets and maps unlock the collective value of several decades of geochronological and isotopic studies conducted across Australia, and provide an important complement to other geological maps and geophysical images—in particular, by adding a time dimension to 2D and 3D maps and models.</div> Abstract/Poster submitted and presented at 2023 Australian Earth Science Convention (AESC), Perth WA (https://2023.aegc.com.au/)

The National Geochemical Survey of Australia (NGSA) is Australia’s only internally consistent, continental-scale geochemical atlas and dataset (<a href="http://dx.doi.org/10.11636/Record.2011.020">http://dx.doi.org/10.11636/Record.2011.020</a>). The present dataset provides additional geochemical data for Li, Be, Cs, and Rb acquired as part of the Australian Government-funded Exploring for the Future (EFTF) program and in support of the Australian Government’s 2023-2030 Critical Minerals Strategy. The dataset fills a knowledge gap about Li distribution in Australia over areas dominated by transported regolith. The main ‘total’ element analysis method deployed for NGSA was based on making a fused bead using lithium-borate flux for XRF then ICP-MS analysis. Consequently, the samples could not be meaningfully analysed for Li. All 1315 NGSA milled coarse-fraction (<2 mm) top (“TOS”) catchment outlet sediment samples, taken from 0 to 10 cm depth in floodplain landforms, were analysed in the current project following the digestion method that provides near-total concentrations of Li, Be, Cs, and Rb. The samples were analysed by the commercial laboratory analysis service provider Bureau Veritas in Perth using low-level mixed acid (a mixture of nitric, perchloric and hydrofluoric acids) digestion with elements determined by ICP-MS (Bureau Veritas methods MA110 and MA112). The data are reported in the same format as the NGSA dataset, allowing for seamless integration with previously released NGSA data. Further details on the QA/QC procedures as well as data interpretation will be reported elsewhere. This data release also includes four continental-scale geochemical maps for Li, Be, Cs, and Rb built from these analytical data. This dataset, in conjunction with previous data published by NGSA, will be of use to mineral exploration and prospectivity modelling around Australia by providing geochemical baselines for Li, Be, Cs, and Rb, as well as identifying regions of anomalism. Additionally, these data also have relevance to other applications in earth and environmental sciences.

<div>Quality assurance and quality control (QAQC) of geochemical data is an important first step before any interpretation of the data is undertaken. Due to the increasing number of elements that are being reported by laboratories undertaking multi-element analysis, the time to undertake QAQC of the data has increased. In order to alleviate the increasing time constraints of undertaking QAQC this python script was developed. This script provides a quick first pass of the data automatically to produce summary statistics and plots of the included standards laboratory duplicates and analytical duplicates. The statistics and plots allow for rapid assessment of geochemical data to discover potential issues with the data and trends though time, whilst also providing a consistent approach. It should be noted that no general quality cut-offs have been included within the script as it does not replace the need for an expert examining the data to identify potential issues.</div>