The first phase of the Australian Government's Exploring for the Future (EFTF) was a multi-year (2016-2020) $100.5 million initiative to increase northern Australia's desirability as a destination for industry investment to stimulate ‘greenfield’ resource exploration. In order to support this fundamental objective of the EFTF program, Geoscience Australia conducted acquisition of a diverse range of new precompetitive datasets across northern Australia, focussing on regions of unrecognised mineral, energy and groundwater resource potential. The Barkly 2D Deep Crustal Reflection Seismic Survey (L212) was acquired in 2019 as a major objective of the EFTF program in partnership with, and co-funded by, the NT Government under the Resourcing the Territory initiative. The Barkly Seismic Survey extends from the newly discovered Carrara Sub-basin in the South Nicholson Basin region to the south-eastern margins of the Beetaloo Sub-basin (Fomin, T., et al. 2019). The Barkly Seismic Survey images interpreted Paleoproterozoic to Mesoproterozoic successions extending from the Carrara Sub-basin to the highly prospective Beetaloo Sub-basin of the McArthur Basin. These successions are concealed by a persistent cover of up to 600 m of Paleozoic Georgina Basin sediments. Interpretation of the Barkly Seismic Survey established three informal geological domains, each defined by structural elements and/or basin characteristics (Southby et al, 2021). This data set contains an exported set of XYZ points from interpreted horizons (Southby et al 2022,) on the Barkly Seismic Survey (L212) in both two way time (TWT ms on PreSTM_19ga lines) and depth (m) re-interpreted on depth indexed PreSDM_19GA lines. The coordinate reference system for this dataset is WGS 1984 Australian Centre for Remote Sensing Lambert. Seismic reference datum is 350 m. The seismic reference datum are described in the EBCDIC headers of the SEGY files for each of the survey lines. Fomin, T., Costelloe, R.D., Holzschuh, J. 2019. L212 Barkly 2D Seismic Survey. Geoscience Australia, Canberra. https://pid.geoscience.gov.au/dataset/ga/132890 Southby, C., Rollet, N., Carson, C., Carr, L., Henson, P., Fomin, T., Costelloe, R., Doublier, M., Close, D. 2021. The Exploring for the Future 2019 Barkly Reflection Seismic Survey: Key discoveries and implication for resources. Geoscience Australia, Canberra. https://pid.geoscience.gov.au/dataset/ga/145107 Southby, C., Carson, C.J., Fomin, T., Rollet, N., Henson, P.A., Carr, L.K., Doublier, M.P., Close, D. 2022. Exploring for the Future - The 2019 Barkly Reflection Seismic Survey (L212). RECORD: 2022/009. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2022.009

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 (Carr et al 2018). The South Nicholson Basin and immediate surrounding region is situated between Paleo-Mesoproterozoic Mount Isa Province and McArthur Basin. Both the Mount Isa Province and McArthur Basin are well studied. By contrast, the adjacent South Nicholson region is less studied, and contains rocks that are mostly undercover, for which the basin evolution and resource potential is not well understood. To address this gap, the L210 South Nicholson Deep Crustal Seismic Survey was collected in 2017 in the region between the southern McArthur Basin to the Mount Isa western succession, crossing the South Nicholson Basin and Murphy Province, providing a fundamental data link across these regions (L210 South Nicholson Deep Crustal Seismic Reflection Survey). The primary aim of the survey was to investigate areas with a low measured gravity response in the region to determine whether they represent thick basin sequences, as is the case for the nearby prospective Beetaloo Sub-basin. The interpretation of this survey led to the discovery of a new basin, the Carrara Sub-basin, coinciding with a gravity low in the south-eastern South Nicholson Basin Region. This data set contains an exported set of XYZ points from interpreted horizons (Carr et al 2019) on the South Nicholson Seismic Survey (L210) in both two way time (TWT ms on PreSTM_17ga lines) and depth (m) re-interpreted on depth indexed PreSDM_17GA lines. The coordinate reference system for this dataset is WGS 1984 Australian Centre for Remote Sensing Lambert. Seismic reference datum is 350 m. The seismic reference datum are described in the EBCDIC headers of the SEGY files for each of the survey lines. Carr, L.K., Southby, C., Henson, P., Costello, R., Anderson, J.R., Jarrett, A.J M., Carson, C.J., Gorton, J., Hutton, L.J., Troup, A., Williams, B., Khider, K., Bailey, A. & Fomin, T. 2019. Exploring for the Future: South Nicholson Basin geological summary and seismic interpretation. Record 2019/21, Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2019.021 Carr, L.K., Southby, C., Henson, P., Anderson, J.R., Costelloe, R., Jarrett, A.J.M., Carson, C.J., MacFarlane, S.K., Gorton, J., Hutton, L., Troup, A, Williams, B., Khider, K., Bailey, A.H.E., Fomin, T. 2020. South Nicholson Basin seismic interpretation. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/132029 L210 South Nicholson Deep Crustal Seismic Reflection Survey, NT and QLD, 2017. Geoscience Australia, Canberra. https://pid.geoscience.gov.au/dataset/ga/116881.

NDI Carrara 1 is a deep stratigraphic drill hole (~1751m) 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. This report presents SHRIMP U-Pb zircon geochronology on 10 volcaniclastic rocks taken from NDI Carrara 1.

In 2017, under the Federal Governments’ Exploring for the Future program, in collaboration with the NTGS under their ‘Resourcing the Territory’ initiative, Geoscience Australia acquired the South Nicholson Deep Crustal Seismic Reflection Survey in north-eastern Northern Territory. One of the key discoveries of this survey was the identification of a large sedimentary depocentre, concealed beneath the sedimentary rocks of the Cambrian Georgina Basin. This depocentre, up to 7 km deep, termed the ‘Carrara Sub-basin’ by Geoscience Australia (e.g. Carr et al., 2020), is interpreted to contain thick sequences of resource-rich Proterozoic rocks, broadly equivalent to rocks of the greater McArthur Basin (Northern Territory) and northern Lawn Hill Platform and Mount Isa Province of northwest Queensland, rocks that are highly prospective for sediment-hosted base metals and unconventional hydrocarbons. The Carrara-1 stratigraphic drillhole was completed in late 2020, as a collaboration between Geoscience Australia, the Northern Territory Geological Survey and the MinEx CRC. Carrara-1 is the first drillhole to intersect the undifferentiated Proterozoic rocks of the Carrara Sub-Basin. 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 m, intersecting ca. 630 m of Cambrian Georgina Basin overlying ca. 1100 m of Proterozoic carbonates, black shales and minor siliciclastics. These rocks preserve evidence of both oil and gas and visible disseminated sulphide mineralisation. Carrara-1 affords us a privileged glimpse into this highly prospective and exciting frontier Proterozoic basin.

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 1120 m of Proterozoic sedimentary rocks unconformably overlain by 630 m of Cambrian Georgina Basin carbonates. Continuous cores recovered from 283 m to a total depth of 1750 m provide samples of the highest quality for a comprehensive geochemical program designed to inform on the energy and mineral prospectivity of the Carrara Sub-basin. Total Organic Carbon (TOC) contents from Rock-Eval pyrolysis of the Cambrian and Proterozoic sections demonstrate the potential for several thick black shales as source rocks and unconventional plays. Evidence for retained hydrocarbons included bituminous oil stains in centimetre-scale vugs within the Cambrian Georgina Basin and several oil bleeds within the Proterozoic section. The latter also contains surface gas with up to 2% methane concentrations measured within carbonaceous mudstones. Geochemical analyses of hydrocarbon shows highlight the occurrence of several petroleum systems operating in this frontier region. The results at NDI Carrara 1 offer the promise of a new exciting resource province in northern Australia.

Exploring for the Future (EFTF) is an Australian Government initiative that gathers new data and information about potential mineral, energy and groundwater resources. Commencing in 2016 with a focus on northern Australia, an EFTF extension to 2024 was recently announced, with expanded coverage across mainland Australia and Tasmania. The EFTF energy component aims to improve our understanding of the petroleum potential of frontier onshore Australian basins and has acquired significant pre-competitive datasets, including the recently drilled Barnicarndy 1 deep stratigraphic well in Western Australia’s Canning Basin (in partnership with the Geological Survey of Western Australia), and NDI Carrara 1 deep stratigraphic well in the South Nicholson region of the Northern Territory (in partnership with the MinEX CRC). These are the first stratigraphic wells drilled in a petroleum basin by Geoscience Australia since the formation in 2001 from its predecessor agencies. Both wells were sited along two-dimensional, deep crustal seismic surveys acquired by Geoscience Australia as part of EFTF, and provide stratigraphic control for the imaged geology. The sedimentary fill intersected by the Barnicarndy 1 and NDI Carrara 1 wells were cored and logged with a broad suite of wireline tools, providing substantial new data in two frontier basins. These data provide insights into regional stratigraphy and local lithology. Geochronology, petrographic, organic and inorganic geochemistry, petrophysical rock properties, petroleum systems elements, palaeontological, and fluid inclusion studies have been undertaken upon which inferences on regional prospectivity can made in these data-poor regions. Moving into the next phase of EFTF, these wells provide a template for new pre-competitive data acquisition by Geoscience Australia, expanding our knowledge of frontier regions making them attractive for new investment and exploration.

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.

<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)

NDI Carrara 1 is a deep stratigraphic drill hole (~1751m) 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. This report presents inorganic geochemical analyses undertaken by Geoscience Australia on selected rock samples, collected at roughly 4 m intervals.

The NDI Carrara 1 sedimentology, microstructural analysis and sequence stratigraphy program was a joint undertaking between Geoscience Australia (GA) and CSIRO (Perth) as part of the Exploring for the Future program to examine the sedimentology, sequence stratigraphy and paleogeography of the Carrara Sub-basin. The program was based on recovered core from the National Drilling Initiative (NDI) deep stratigraphic drill hole, 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. This final report, and associated appendices, compiles the findings of three milestone deliverables. The first component of the report addresses the sedimentology of the Proterozoic section of NDI Carrara 1 with an accompanying Appendix (core log, from HyLogger data). The second component is a detailed microstructural analysis based on selected thin sections in intervals of interest. The final component completed a 1D sequence stratigraphic assessment, enabling regional stratigraphic correlations to be established and an interpretive paleogeographic map generated for the Proterozoic sequences of interest across the region .