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  • <div>NDI Carrara 1 is a deep stratigraphic borehole that was drilled in 2020 under the MinEx CRC’s National Drilling Initiative (NDI) program in collaboration with Geoscience Australia and the Northern Territory Geological Survey. NDI Carrara 1 is the first stratigraphic test of the recently described Carrara Sub-basin, a Proterozoic aged depocentre located in the South Nicholson region of northwest Queensland and the Northern Territory. The borehole was drilled to a total depth of 1751 m and penetrated a succession of Cambrian aged Georgina Basin carbonate and siliciclastic rocks that unconformably overly a thick succession of Proterozoic age siliciclastic and carbonate-rich sediments. Although drilled on the western flank of the Carrara Sub-basin, NDI Carrara 1 did not penetrate to basement. Interpretation of the L210 deep-crustal seismic survey suggests that further Proterozoic sedimentary packages known from the northern Lawn Hill Platform in northwest Queensland are likely to be found underlying the succession intersected in NDI Carrara 1. The borehole was continuously cored from 283 m to total depth, and an extensive suite of wireline logs was acquired. Geoscience Australia and partners have undertaken an extensive analytical program to understand the depositional, structural, and diagenetic history of the sediments intersected in NDI Carrara 1. This program includes a targeted petrophysical study that aims to characterise the physical properties of these Proterozoic rocks through laboratory analysis of core samples, the results of which are summarised in this data release.</div><div><br></div><div>This data release provides data from new X-ray Computerised Tomography (XCT) scanning and gas porosity and permeability testing for 32 samples from NDI Carrara 1. Additional low permeability tests were undertaken on select samples that were identified as being ultra-tight (permeability <1 μD). These tests were performed at the CSIRO Geomechanics and Geophysics Laboratory in Perth, during January to June 2022. The full results as provided by CSIRO to Geoscience Australia are provided as an attachment to this document.&nbsp;</div>

  • The National Drilling Initiative (NDI) will manage and deliver drilling programs in multiple case study areas proposed by MinEx CRC’s partner geological survey organisations. The NDI vision is to drill multiple holes in a region to map the regional geology and architecture and define the potential for mineral systems in 3D. The areas shown in this web service describe the spatial locations of the study areas.

  • <div>The Carrara Sub-basin, discovered in 2017 based on interpretation of 2D deep seismic surveys acquired by Geoscience Australia, is a large sedimentary depocentre in the South Nicholson region straddling the Northern Territory and Queensland. It was interpreted to contain up to 8 km of Paleoproterozoic to Cambrian rocks including stratigraphic equivalents to the Isa Superbasin, South Nicholson Group and Georgina Basin. In order to validate these stratigraphic interpretations and assess the resource prospectivity of the Carrara Sub-basin, the South Nicholson National Drilling Initiative (NDI) Carrara 1 stratigraphic drill hole was completed in late 2020 as a collaboration between the MinEx Cooperative Research Centre, Geoscience Australia and the Northern Territory Geological Survey. NDI Carrara 1 was drilled on the western flanks of the Carrara Sub-basin and reached a total depth of 1751&nbsp;m, intersecting ca. 630&nbsp;m of Cambrian Georgina Basin overlying ca. 1100&nbsp;m of Proterozoic carbonates, black shales and minor siliciclastics. More than 400 NDI Carrara&nbsp;1 physical samples were analysed as part of an extensive geochemical program, including Rock-Eval pyrolysis and compositional analyses of hydrocarbon shows, whose results and implications for energy prospectivity are summarised here.</div> This Abstract was submitted/presented to the 2022 Australian Organic Geochemistry Conference 27-29 November (https://events.csiro.au/Events/2022/October/5/Australian-Organic-Geochemistry-Conference)

  • <div>A multi-disciplinary program of geological and geophysical data collection and integration, focussed on the Delamerian Orogen, was undertaken as part of Geoscience Australia’s Exploring for the Future (EFTF) program and the Mineral Exploration Cooperative Research Centres (MinEx CRC) National Drilling Initiative (NDI).&nbsp;In this study, we integrate learnings from these data with existing geological and geophysical data to refine the basement geology of the Loch Lilly-Kars Belt, Lake Wintlow Belt and Wilcannia High. Our interpretation provides a revised geological framework for a frontier exploration region in the Delamerian Orogen.&nbsp;This product includes ESRI shape files and layer files, accompanying notes, and several appendices containing new detrital zircon U-Pb geochronology data from the map area as well as the broader Delamerian Orogen.</div>

  • The National Drilling Initiative (NDI) will manage and deliver drilling programs in multiple case study areas proposed by MinEx CRC’s partner geological survey organisations. The NDI vision is to drill multiple holes in a region to map the regional geology and architecture and define the potential for mineral systems in 3D. The areas shown in this web service describe the spatial locations of the study areas.

  • The National Drilling Initiative (NDI) will manage and deliver drilling programs in multiple case study areas proposed by MinEx CRC’s partner geological survey organisations. The NDI vision is to drill multiple holes in a region to map the regional geology and architecture and define the potential for mineral systems in 3D. The areas shown in this web service describe the spatial locations of the study areas.

  • <div>This study was commissioned by Geoscience Australia (GA) to produce a report on methane adsorption and desorption of select samples from the deep stratigraphic drill hole NDI Carrara 1, located in the Proterozoic Carrara Sub-basin in the Northern Territory. Plugs were taken from depths of interest and analysed via adsorption and desorption isotherm testing at the CSIRO laboratories in Clayton, Victoria. </div>

  • <div>NDI Carrara&nbsp;1 is a 1751 m stratigraphic drill hole completed in 2020 as part of the MinEx CRC National Drilling Initiative (NDI). This campaign was a collaboration between Geoscience Australia under the Exploring for the Future program, together with MinEx CRC and the Northern Territory Geological Survey. It is the first drillhole to intersect Proterozoic rocks of the Carrara Sub-basin, a recently discovered depocentre in the South Nicholson region. The drill hole intersected ~625 m of the Paleozoic Georgina Basin, which overlies ~1120 m of Proterozoic carbonates, black shales and siliciclastic rocks, with hydrocarbon shows encountered in both the Paleozoic and Proterozoic sections. Following the completion of the drillhole, a comprehensive analytical program was carried out by Geoscience Australia to better understand the geology of the Carrara Sub-basin and its resource potential.</div><div><br></div><div>Here we present new high-resolution strontium (87Sr/86Sr), carbon (δ13C) and oxygen (δ18O) isotope data from carbonate bearing samples of the Paleozoic Georgina Basin and the Proterozoic Lawn Hill Formation intersected in NDI Carrara&nbsp;1. The aim of this data acquisition was to provide an improved understanding of the paleo-depositional environments and local/global chemostratigraphy trends recorded in the Carrara Sub-basin. </div><div><br></div><div>The majority of samples show significant alteration and thus caution should be exercised when using this data for assessing primary depositional conditions and contemporary sea-water chemistry. Despite the altered nature of most samples, samples belonging to undifferentiated Georgina Basin preserve 87Sr/86Sr ratios close to that of mid-Cambrian seawater, indicating the sampled intervals of Georgina Basin were likely connected to the global Cambrian ocean.&nbsp;Two small positive δ13C excursions (with positive shift in δ18O) within Georgina Basin samples may coincide with reported mid-Cambrian positive δ13C global marine excursions. </div><div><br></div><div>The least altered samples from the Proterozoic Lawn Hill Formation show more radiogenic 87Sr/86Sr values than the expected value of coeval mid-Proterozoic ocean at ~1600 Ma. These radiogenic 87Sr/86Sr values may reflect (i) influx of terrigenous material into a restricted basin with reduced interaction with the global ocean, or (ii) secondary overprinting by more radiogenic diagenetic fluids.</div> Abstract/Poster submitted and presented at 2023 Australian Earth Science Convention (AESC), Perth WA (https://2023.aegc.com.au/)

  • As part of Geoscience Australia's Exploring for the Future program, the East Tennant region, which is centred on the Barkly Roadhouse in the Northern Territory, was identified as having favourable geological and geophysical indicators of mineral systems potential. Potentially prospective stratigraphy in the East Tennant region is completely concealed beneath Mesoproterozoic to Quaternary cover sequences. Prior to 2020 basement rocks in the East Tennant region were only known from a handful of legacy boreholes, supported by geophysical interpretation. In order to test geophysical interpretations and obtain additional samples of basement rocks for detailed analysis, a stratigraphic drilling campaign was undertaken in the East Tennant region as part of the MinEx CRC’s National Drilling Initiative. Ten stratigraphic boreholes were drilled through the cover sequences and into basement for a total of nearly 4000 m, including over 1500 m of diamond cored basement rocks to be used for scientific purposes. Inorganic geochemical samples from East Tennant National Drilling Initiative boreholes were taken to characterise cover and basement rocks intersected during drilling. Two sampling approaches were implemented based on the rocks intersected: 1) Borehole NDIBK04 contained localised sulphide mineralisation and elevated concentrations of several economically-significant elements in portable X-ray fluorescence data. In order to understand the geochemical variability and distribution of elements important for mineral system characterisation, the entire basement interval was sampled at nominal one metre intervals. This spacing was reduced to between 0.5 and 0.25 m from 237 m to 263 m to better understand a more intense zone of mineralisation, and 2) Samples from boreholes NDIBK01, NDIBK02, NDIBK03, NDIBK05, NDIBK06, NDIBK07, NDIBK08, NDIBK09 and NDIBK10 were selected to capture lithological and geochemical variability to establish bulk rock geochemical compositions for further interpretation. Attempts were made to sample representative, lithologically consistent intervals. A total of 402 samples were selected for analysis. Sample preparation was completed at Geoscience Australia and Bureau Veritas, with all analyses performed by Bureau Veritas in Perth. All samples were submitted for X-ray fluorescence (XRF), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), FeO determination, and loss on ignition (LOI). Samples from borehole NDIBK04 also underwent total combustion C and S, and Pb collection fire assay by ICP-MS for determination of Au, Pt and Pd concentrations. This data release presents inorganic geochemistry data acquired on rock samples from the ten East Tennant National Drilling Initiative boreholes.

  • NDI Carrara 1 is a deep stratigraphic well 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 stratigraphic test of the Carrara Sub-Basin, a newly discovered depocentre in the South Nicholson region. The well intersected Proterozoic sediments with numerous hydrocarbon shows, likely to be of particular interest due to affinities with the known Proterozoic plays of the Beetaloo Sub-basin and the Lawn Hill Platform, including two organic-rich black shales and a thick sequence of interbedded black shales and silty-sandstones. Alongside an extensive suite of wireline logs, continuous core was recovered from 283.9 m to total depth at 1750.8 m, providing high-quality data to support comprehensive analysis. Presently, this includes geochronology, geochemistry, geomechanics, and petrophysics. Rock Eval pyrolysis data demonstrates the potential for several thick black shales to be a source of hydrocarbons for conventional and unconventional plays. Integration of these data with geomechanical properties highlights potential brittle zones within the fine-grained intervals where hydraulic stimulation is likely to enhance permeability, identifying prospective Carrara Sub-basin shale gas intervals. Detailed wireline log analysis further supports a high potential for unconventional shale resources. Interpretation of the L210 and L212 seismic surveys suggests that the intersected sequences are laterally extensive and continuous throughout the Carrara Sub-basin, potentially forming a significant new hydrocarbon province and continuing the Proterozoic shale play fairway across the Northern Territory and northwest Queensland. This abstract was submitted and presented at the 2022 Australian Petroleum Production and Exploration Association (APPEA), Brisbane (https://appea.eventsair.com/appea-2022/)