<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>

Manuscript detailing the results of chlorite dissolution experiments conducted at Geoscience Australia.

<b>IMPORTANT NOTICE:</b> This web service has been deprecated. The Hydrochemistry Service OGC service at https://services.ga.gov.au/gis/hydrogeochemistry/ows should now be used for accessing Geoscience Australia hydrochemistry analyses data. This is an Open Geospatial Consortium (OGC) web service providing access to hydrochemistry data (groundwater analyses) obtained from water samples collected from Australian water bores.

Brumbys 1 was an appraisal well drilled and cored through Brumbys Fault at the CO2CRC Otway International Test Centre in 2018. The Otway Project is located in South West Victoria, on private farming property approximately 35 km southeast of Warrnambool and approximately 10 km northwest of the town of Peterborough. Total measured depth was 126.6 m (80 degrees). Sonic drilling enabled excellent core recovery and the borehole was completed as a groundwater monitoring well. Brumbys 1 cores through the upper Hesse Clay, Port Campbell Limestone and extends into the Gellibrand Marl. This dataset compiles the extensive analysis undertaken on the core. Analysis includes: Core log; Foram Analysis; Paleodepth; % Carbonate (CaCO3); X-Ray Fluorescence Spectrometry (XRF); Inductively Coupled Plasma Mass Spectrometry (ICP-MS); X-Ray Diffraction (XRD); Grain Size; Density; Surface Area Analysis (SAA); Gamma. Samples were taken at approximately 1-2 m intervals.

As part of the Exploring for the Future (EFTF) program, a chemostratigraphic framework for the Officer Basin was developed that correlates inorganic geochemical sequences between exploration wells. The Officer Basin spans 525,000 km² across Western Australia and South Australia, where it remains an unproven frontier basin which has seen little exploration. The objective of this study was to undertake a bulk rock elemental chemostratigraphy study on ten historic wells in order to better correlate the Neoproterozoic and Cambrian sections. Ten study wells, five from Western Australia and five from South Australia, were selected, and core (241) and cuttings (1,245) samples were acquired from their respective state core libraries. All samples were analysed using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), resulting in quantitative data for 50 elements. The approximate proportions of dolomite, clastics, halite and anhydrite for the samples were derived using stoichiometric geochemical calculations. Halite was identified in some formations based on mud log and wireline data, but was not always preserved in the cuttings samples. This non-detection of halite resulted in poor matches between the wireline gamma ray (GR) and ChemGR profiles for halite-bearing units in some wells (e.g. Dragoon-1, Mulyawara-1, and Yowalga-3). Key element and ratios utilised to subdivide the strata were principally chosen to highlight changes in sediment provenance, climatic, and organic matter changes, as they typically have the best correlation potential over a greater distance. The stratigraphy within the study wells has been subdivided into eight chemostratigraphic mega-sequences referred to as MS1 to MS8, which are further subdivided into a total of twenty-four sequences. Mega-Sequences MS1 to MS4 broadly correspond to the published Neoproterozoic–Cambrian Centralian Supersequences (CS1 to CS4). While overall there is broad agreement between these two schemes, there are also sections where the stratigraphy has been reassigned. For example, within Kutjara-1, the section previously assigned to Centralian Supersequence CS2, and equivalent to the Cryogenian Tapley Hill Formation, is assigned to Mega-Sequence MS3 (not MS2). Within MS4, the lithostratigraphically defined members of the Observatory Hill Formation show some significant variation to the chemostratigraphy, with differences occurring within sequences MS4-S3, MS4-S4 and MS4-S5 (e.g. Birksgate-1; Trainor Echo-1). Mega-Sequence MS6 encompasses the Mount Chandler Sandstone in Trainor Echo-1 in the east and the lithological lateral equivalent Lennis Sandstone in Lungkarta-1/ST1 and Yowalga-1 in the west; however, these two argillaceous sandstones are chemically distinct. Carbonate-containing samples from three wells (Birksgate-1, Yowalga-3, and Giles-1) were analysed for their δ13Ccarb and δ18Ocarb isotope signature using Isotope-Ratio Mass Spectrometry (IRMS), with results from the least altered carbonates being of sufficient quality to attempt preliminary age dating. Comparison of the Officer Basin isotope data to global type sections enabled tentative correlation of the Yowalga-3 carbonates to the Tonian and late Ediacaran, and the Birksgate-1 carbonates to the early Cambrian. The geochemistry analyses from 10 basin-wide wells provide a robust dataset that has been used to confirm which sections correlate within the existing lithostratigraphic and sequence stratigraphic framework. This study also highlights where further work needs to be undertaken to elucidate the spatial and temporal relationships of some Cryogenian and early Cambrian sections across the entire basin, given that rocks of these ages contain both potential source and reservoir rocks for petroleum generation and accumulation.

This report presents the results of an elemental and carbon and oxygen isotope chemostratigraphy study on three historic wells; Kidson-1, Willara-1 and Samphire Marsh-1, from the southern Canning Basin, Western Australia. The objective of this study was to correlate the Early to Middle Ordovician sections of the three wells to each other and to wells with existing elemental and carbonate carbon isotope chemostratigraphy data from the Broome Platform, Kidson and Willara sub-basins, and the recently drilled and fully cored stratigraphic Waukarlycarly 1 well from the Waukarlycarly Embayment.

<div>Geochemistry of soils, stream sediments, and overbank sediments, plays an important part in informing geochemical environmental baselines, mineral prospectivity, and environmental management practices. Australia has a large number of such surveys, but they are spatially isolated and often used in isolation. First released in 2020, the Levelled Geochemical Baseline of Australia focused on levelling such surveys across the North Australian Craton, so that they could be used as a seamless dataset. This data release acts as an update to the Levelled Geochemical Baseline of Australia by changing the focus to national scale and incorporating recently reanalysed legacy samples.</div><div><br></div><div>This work was undertaken as part of the Exploring for the Future program, an eight-year program by the Australian government. The Exploring for the Future program provides precompetitive information to inform decision-making by government, community and industry on the sustainable development of Australia's mineral, energy and groundwater resources. By gathering, analysing and interpreting new and existing precompetitive geoscience data and knowledge, we are building a national picture of Australia’s geology and resource potential. This leads to a strong economy, resilient society and sustainable environment for the benefit of all Australians. This includes supporting Australia’s transition to net zero emissions, strong, sustainable resources and agriculture sectors, and economic opportunities and social benefits for Australia’s regional and remote communities. The Exploring for the Future program, which commenced in 2016, was an eight year, $225m investment by the Australian Government.</div><div><br></div><div><br></div><div><br></div><div><br></div>

Paleoproterozoic arc and backarc assemblages accreted to the south Laurentian margin between 1800 Ma and 1600 Ma, and previously thought to be indigenous to North America, more likely represent fragments of a dismembered marginal sea developed outboard of the formerly opposing Australian-Antarctic plate. Fugitive elements of this arc-backarc system in North America share a common geological record with their left-behind Australia-Antarctic counterparts, including discrete peaks in tectonic and/or magmatic activity at 1780 Ma, 1760 Ma, 1740 Ma, 1710-1705 Ma, 1690-1670 Ma, 1650 Ma and 1620 Ma. Subduction rollback, ocean basin closure and the arrival of Laurentia at the Australian-Antarctic convergent margin first led to arc-continent collision at 1650-1640 Ma and then continent-continent collision by 1620 Ma as the last vestiges of the backarc basin collapsed. Collision induced obduction and transfer of the arc and more outboard parts of the Australian-Antarctic backarc basin onto the Laurentian margin where they remained following later breakup of the Neoproterozoic Rodinia supercontinent. North American felsic rocks generally yield Nd depleted mantle model ages consistent with arc and backarc assemblages built on early Paleoproterozoic Australian crust as opposed to older Archean basement making up the now underlying Wyoming and Superior cratons. Appeared in Lithosphere (2019) 11 (4): 551–559, June 10, 2019.

The stabilities of uranyl-carbonate and uranyl-hydroxide aqueous complexes were experimentally determined at temperatures ranging from 25 to 125 °C using in situ UV–vis and Raman spectroscopic techniques. Combined with earlier determinations of the stability of chloride, sulfate, and hydroxide complexes at temperatures up to 250 °C, these data permit to create a consolidated dataset suitable for modeling of U(VI) mobilization in natural systems. The parameters of the Modified Ryzhenko-Bryzgalin and the Helgeson-Kirkham-Flowers (HKF) Equations of State (EoS) were derived based on this dataset and used for thermodynamic modeling different scenarios of U(VI) mobilization. These models suggest that at conditions relevant to natural systems, carbonate-mediated transport of U(VI) is likely suppressed by the high stability of solid UO2(OH)2 and Na2U2O7. In contrast, sulfate-mediated mobilization mechanisms are highly efficient at acidic and near-neutral pH conditions and can lead to effective hydrothermal mobilization of U(VI). <b>Citation:</b> A. Migdisov, E. Bastrakov, C. Alcorn, M. Reece, H. Boukhalfa, F.A. Capporuscio, C. Jove-Colon, A spectroscopic study of the stability of uranyl-carbonate complexes at 25–150 °C and re-visiting the data available for uranyl-chloride, uranyl-sulfate, and uranyl-hydroxide species, <i>Geochimica et Cosmochimica Acta</i>, 2024, ISSN 0016-7037, https://doi.org/10.1016/j.gca.2024.04.023.

The Neoproterozoic to Middle Ordovician sediments of the Officer Basin, Australia are difficult to correlate, in part because biostratigraphic studies of acritarchs and stromatolites are localised, isotopic studies are rare, and seismic models are technically challenged by the occurrence of basaltic and halite prone-sections. Hence, the chemostratigraphic framework presented here provides an independent stratigraphic model for the Neoproterozoic to Middle Ordovician sediments of the Officer Basin. A total of six chemostratigraphic mega-sequences have been geochemically defined and assigned to the stratigraphy; these have been further subdivided into twenty-eight chemostratigraphic sequences. The chemostratigraphic zonation has been established upon elemental changes attributed to provenance and climatic variation which can be used for correlation as they convey regional, rather than local, changes in sedimentation. The elemental data reveals that there is lateral variation within the established lithostratigraphy (e.g., within the members of the Observatory Hill and Hussar formations), which is suggestive of localised sediment source input to different areas of the basin. Presented to the 2022 Central Australian Basins Symposium IV (CABS) 29-30 August (https://agentur.eventsair.com/cabsiv/)