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  • The Exploring for the Future Program (EFTF) is a $100.5 million four year, federally funded initiative to better characterise the mineral, energy and groundwater potential of northern Australia. A key focus area of the initiative is the South Nicholson region, situated across the Northern Territory and Queensland border. The South Nicholson region is located between two highly prospective provinces, the greater McArthur Basin in the Northern Territory, the Lawn Hill Platform and the Mount Isa Province in Queensland–Northern Territory, which both have demonstrated hydrocarbon and base metal resources. In contrast, the South Nicholson region is not well understood geologically, is mostly undercover with limited well data, and prior to EFTF contained limited seismic coverage. Re–Os analyses in this study were undertaken to complement seismic data, U–Pb geochronology and geochemistry data to better understand the geological evolution and resource potential of the South Nicholson region. Five organic carbon bearing sedimentary samples from drillholes BMR Ranken 1, NTGS00/1, DDH 83/1 and DDH 83/4 located across the South Nicholson region were analysed for whole rock Re–Os. The aim of the analyses was to better constrain the depositional age of basin units in the region, and to potentially provide insights into the timing of post-depositional processes such as fluid events and hydrocarbon generation and/or migration. Samples belong to the Mesoproterozoic South Nicholson Group, Paleoproterozoic Fickling and McNamara groups, and the Neoproterozoic to Devonian Georgina Basin. Samples were analysed at the University of Alberta, Canada.

  • The upper Permian to Lower Triassic sedimentary succession in the southern Bonaparte Basin represents an extensive marginal marine depositional system that hosts several gas accumulations. Of these, the Blacktip gas field has been in production since 2009, while additional identified gas resources are under consideration for development. The sedimentary succession extends across the Permian–Triassic stratigraphic boundary, and shows a change in lithofacies changes from the carbonate dominated Dombey Formation to the siliciclastic dominated Tern and Penguin formations. The timing, duration, distribution and depositional environments of these formations in the Petrel Sub-basin and Londonderry High is the focus of this study. The sedimentary succession extending from the Dombey to the Penguin formations is interpreted to represent marginal marine facies which accumulated during a long-lasting marine transgression that extended over previous coastal and alluvial plain sediments of the Cape Hay Formation. The overlying Mairmull Formation represents the transition fully to marine deposition in the Early Triassic. Regional scale well correlations and an assessment of available biostratigraphic data suggest marginal marine deposition systems were initiated outboard before the End Permian Extinction event, subsequently migrated inboard at about the Permian–Triassic stratigraphic boundary, and continued to be deposited through the faunal and floral recovery phase as Triassic species became established. The depositional history of the basin is translated to a chronostratigraphic framework which has implications for predicting the character and distribution of petroleum system elements in the Petrel Sub-basin and Londonderry High. Appeared in The APPEA Journal 61(2) 699-706, 2 July 2021

  • The NDI Carrara 1 Sedimentology and Sequence Stratigraphy program has been undertaken by CSIRO (Perth) under contract to Geoscience Australia as part of the Exploring for the Future program to examine the sedimentology, sequence stratigraphy and paleogeography of the Carrara Sub-basin based on recovered core from NDI Carrara 1. NDI Carrara 1 is the first drill hole to intersect the Proterozoic rocks of the Carrara Sub-Basin, a large depocentre discovered during seismic acquisition conducted during the first phase of the EFTF program in 2017. NDI Carrara 1 is located on the western flanks of the Carrara Sub-basin, reaching a total depth of 1751 m, intersecting ca. 630 m of Cambrian Georgina Basin overlying ca. 1100 m of Proterozoic carbonates, black shales and siliciclastics. The contract will be reported on through three milestone deliverables or 'Packages'. Interim reports on each package will be released and made public following review and approval, however, retroactive revision of released interim milestone reports may be conducted as further information, data analysis and interpretation is completed. This Package 1 milestone interim report (and accompanying Appendix) is a contracted milestone deliverable, on the sedimentology of the Proterozoic section of the National Drilling Initiative (NDI) drill hole Carrara 1 with an accompanying Appendix (Core log, from HyLogger data). Subsequent Package 2 and 3 reports will be publicly released as they are made available and reviewed.

  • Resources for promoting the use of the Australian Stratigraphic Units Database and proper stratigraphic nomenclature.

  • This report was compiled and written to summarise the four-year Palaeovalley Groundwater Project which was led by Geoscience Australia from 2008 to 2012. This project was funded by the National Water Commission's Raising National Water Standards Program, and was supported through collaboration with jurisdictional governments in Western Australia, South Australia and the Northern Territory. The summary report was published under the National Water Commission's 'Waterlines' series. This document is supported by related publications such as the palaeovalley groundwater literature review, the WASANT Palaeovalley Map and associated datasets, and four stand-alone GA Records that outline the detailed work undertaken at several palaeovalley demonstration sites in WA, SA and the NT. Palaeovalley aquifers are relied upon in outback Australia by many groundwater users and help underpin the economic, social and environmental fabric of this vast region. ‘Water for Australia’s arid zone – Identifying and assessing Australia’s palaeovalley groundwater resources’ (the Palaeovalley Groundwater Project) investigated palaeovalleys across arid and semi-arid parts of Western Australia (WA), South Australia (SA) and the Northern Territory (NT). The project aimed to (a) generate new information about palaeovalley aquifers, (b) improve our understanding of palaeovalley groundwater resources, and (c) evaluate methods available to identify and assess these systems.

  • The Australian Government, through the National Water Infrastructure Fund – Expansion, commissioned Geoscience Australia (GA) to undertake the project ‘Assessing the Status of Groundwater in the Great Artesian Basin’ (GAB). The project commenced in July 2019 and will finish in June 2022. The aim of the project is to develop and evaluate new tools and techniques to assess the status of GAB groundwater system to support responsible management of basin water resources. A critical relationship exists between sediment depositional architecture and groundwater flow within and between GAB aquifers, and their connectivity with underlying and overlying aquifers. Little is known about lateral and vertical facies variation within the hydrogeological units and potential compartmentalisation and connectivity across the GAB. To improve the understanding of distribution and characteristics of Jurassic and Cretaceous sediments across the Eromanga/Galilee/Surat basins region, GA is compiling, processing and correlating a variety of well log data. Correlations have been made between geological units of similar age using palynological data from 322 key wells along 28 regional transects to standardise lithostratigraphic units, which are currently described using varying nomenclature, to a single chronostratigraphic chart across the entire GAB. The distribution of generalised sand/shale ratios calculated for 236 wells in the Surat and Eromanga basins are used to estimate the thickness of sand and shale in the different formations, with implications for formation porosity and the hydraulic properties of aquifers and aquitards. This study highlights regional lithological heterogeneity in each hydrogeological unit, and contributes to our understanding of connectivity within and between aquifers. This report and associated data package provide a first phase of data compilation on 322 key wells in the Surat and Eromanga basins to assist in updating the geological framework for the GAB. A data gap analysis and recommendations for building on this initial work are also provided.

  • Exploring for the Future (EFTF) is an Australian Government program led by Geoscience Australia, in partnership with state and Northern Territory governments. The first phase of the EFTF program (2016-2020) aimed to drive industry investment in resource exploration in frontier regions of northern Australia by providing new precompetitive data and information about their energy, mineral and groundwater resource potential. One of the key discoveries of the first phase of the Exploring for the Future program was the identification of a large sedimentary depocentre in the South Nicholson region, an underexplored area straddling north-eastern Northern Territory and north-western Queensland. This depocentre, up to 8 km deep, was termed the ‘Carrara Sub-basin’ by Geoscience Australia. It is interpreted to contain thick sequences of Proterozoic rocks, broadly equivalent to rocks of the greater McArthur Basin (Northern Territory) and northern Lawn Hill Platform and Mount Isa Province (Queensland), known to be highly prospective for sediment-hosted base metals and unconventional hydrocarbons. In order to gain insights into the resource potential of the Carrara Sub-basin, the South Nicholson National Drilling Initiative (NDI) Carrara 1 stratigraphic drillhole was completed in late 2020, as a collaboration between Geoscience Australia, the Northern Territory Geological Survey (NTGS) and the MinEx CRC . NDI Carrara 1 is the first drillhole to intersect the, as yet, undifferentiated Proterozoic rocks of the Carrara Sub-Basin. NDI Carrara 1 is located on the western flanks of the Carrara Sub-basin on the South Nicholson Seismic line (17GA-SN1), reaching a total depth of 1751 mGL, intersecting ca. 630 m of Cambrian Georgina Basin overlying ca. 1100 m of Proterozoic carbonates, black shales and minor siliciclastics . Geoscience Australia is undertaking a range of investigations on the lithology, stratigraphy and geotechnical properties of NDI Carrara 1 based on wireline data, as well as undertaking a range of analyses of over 400 physical samples recovered through the entire core. This report presents new data from bulk density measurements carried out on selected rock samples as part of this comprehensive analytical program.

  • NDI Carrara 1 is a deep stratigraphic drill hole completed in 2020 as part of the MinEx CRC National Drilling Initiative (NDI) in collaboration with Geoscience Australia and the Northern Territory Geological Survey. It is the first test of the Carrara Sub-Basin, a depocentre newly discovered in the South Nicholson region based on interpretation from seismic surveys (L210 in 2017 and L212 in 2019) recently acquired as part of the Exploring for the Future program. The drill hole intersected approximately 1100 m of Proterozoic sedimentary rocks uncomformably overlain by 630 m of Cambrian Georgina Basin carbonates. A comprehensive geochemical program designed to provide information about the region’s resource potential was carried out on samples collected at up to 4 meter intervals. This report presents data from Rock-Eval pyrolysis analyses undertaken by Geoscience Australia on selected rock samples to establish their total organic carbon content, hydrocarbon-generating potential and thermal maturity.

  • 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.

  • We present a new geological map of Warrumbungle Volcano created from volcanic facies field mapping, new geophysical, geochemical, and geochronological data as well as data from previous studies. Field mapping and petrography defined 19 volcanic and 2 mixed volcanic-sedimentary facies. Facies identification and distribution in conjunction with geochemical analyses indicate an early shield-forming phase of predominantly mafic and intermediate lavas and pyroclastic deposits, and minor felsic lavas deposited on an irregularly eroded basement of Surat and Gunnedah basin rocks. The shield was subsequently intruded by felsic intermediate to felsic magmas that formed dykes and other intrusions including possible cryptodomes, and also erupted as lava domes and block-and-ash-flow deposits. A radial dyke swarm cross-cuts most units, although is concentrated within basement sandstone surrounding the central area of the volcano, suggesting late inflation accompanied by dyke emplacement. Geochemistry indicates differentiation of a single although repeatedly recharged alkaline magmatic suite. Fractionation of olivine, Ti-magnetite and clinopyroxene occurred in mafic magmas, and after reaching 62 wt% SiO2 crystallisation of apatite and alkali feldspar took place. A new U-Pb zircon SHRIMP magmatic crystallisation age of 16.25 +/- 0.12 Ma on a felsic block-and-ash flow deposit is in agreement with the recalculated 40Ar/39Ar isochron dates of previous workers. Based on our mapping and the use of volcanic facies to define mappable units, we recommend the previous Warrumbungle Volcanics be elevated from formation to group status and renamed the Warrumbungle Volcanic Complex.