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. As part of this initiative, this record presents new whole-rock geochemistry data from 967 samples of sedimentary rocks sampled from 26 wells in the South Nicholson region, including the Proterozoic South Nicholson Basin and Lawn Hill Platform, the Neoproterozoic to Devonian Georgina Basin and the Jurassic to Cretaceous Carpenteria Basin. This work complements other components of the EFTF program, including the South Nicholson Basin seismic survey, a comprehensive geochronology program and hydrocarbon prospectivity studies to better understand the geological evolution and basin architecture of the region, and facilitate identification of areas of unrecognised resource potential and prospectivity. The South Nicholson region, straddling north-eastern Northern Territory and north-western Queensland, arguably represents one of the least geologically understood regions of Proterozoic northern Australia. The South Nicholson region is situated between two highly prospective provinces, the greater McArthur Basin in the Northern Territory, the Lawn Hill Platform and the Mount Isa Province in Queensland, both with demonstrated hydrocarbon and base metal potential. These new geochemical data provide baseline understanding of regional resource prospectivity of sedimentary rocks in the South Nicholson region. During 2017 and 2018, 967 drill core and cuttings were sampled from 26 legacy boreholes that intersected the South Nicholson region housed in Northern Territory Geological Survey’s core repository in Darwin, the Geological Survey of Queensland’s core repository in Brisbane and Geoscience Australia’s core repository in Canberra. This data release contains the results of elemental analyses on these samples, which include X-Ray Fluorescence (XRF), Loss-On-Ignition (LOI), Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) for all samples, in addition to ron titration (FeO) for selected samples. The data was generated in the Inorganic Geochemistry laboratory at Geoscience Australia between 2017 and 2019 as part of the EFTF program. All data was quality controlled based on Certified Reference Material standards (CRMs) and duplicate samples analysed with each batch of samples.

The South Nicholson region, which includes the Paleoproterozoic Isa Superbasin, the Mesoproterozoic South Nicholson Group and overlying younger sediments, is sparsely explored and has recently come into increased focus as a result of the Australian Government’s Exploring for the Future program. Previous exploration has identified potential shale gas plays within the River and Lawn supersequences of the Isa Superbasin in northwest Queensland’s northern Lawn Hill Platform region. Understanding mineralogy is important for characterising shale reservoirs, as mechanical properties such as shale brittleness are influenced by mineral composition. Mineralogy can, therefore, be utilised as a proxy for mechanical properties that are crucial to minimising risks associated with exploring for and developing shale reservoirs. This study utilises three different methods for calculating brittleness; XRD mineralogy, XRF major element geochemistry, and geomechanical properties. Results indicate highly variable mineralogy within the analysed samples, demonstrating heterogeneity in shale brittleness throughout the studied supersequences. Brittleness calculated from XRD analysis ranges from ductile to brittle with zones of brittle shales present in all supersequences. Increasing quartz and decreasing clay content is the dominant control on shale brittleness in the studied samples. Correlation between XRF major element geochemistry and XRD mineralogy is demonstrated to be moderate to poor, with brittleness derived from XRF major element geochemistry observed to be significantly higher than brittleness derived from XRD mineralogy. Conversely, brittleness derived from geomechanical properties agrees closely with XRD mineralogy derived brittleness. Hence, XRF major element geochemistry data are not recommended in the South Nicholson region to calculate brittleness. Analysis of brittleness indices from this study, in combination with total organic carbon content drawn from regional geochemical analysis in the South Nicholson region, identifies potential shale gas target intervals in the River, Term, and Lawn supersequences. Data presented on correlated well sections highlights intervals of exploration interest within these supersequences, being those depths where high organic content, brittle rocks are identified. The rocks that meet this criteria are primarily constrained to the already known potential shale gas plays of the River and Lawn supersequences. Recent data from Geoscience Australia implies that these potential shale gas plays are likely to extend from the northern Lawn Hill Platform, where they have been primarily identified to date, underneath the South Nicholson Basin and into the Carrara Sub-basin, significantly increasing their lateral extent. <b>Citation:</b> A. H. E. Bailey, A. J. M. Jarrett, L. Wang, B. L. Reno, E. Tenthorey, C. Carson & P. Henson (2022) Shale brittleness within the Paleoproterozoic Isa Superbasin succession in the South Nicholson region, Northern Australia, <i>Australian Journal of Earth Sciences, </i>DOI: 10.1080/08120099.2022.2095029

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/)

The Proterozoic succession in the NDI Carrara 1 drill hole, Northern Territory, consists predominantly of tight shales, siltstones, and calcareous clastic rocks. As part of Geoscience Australia’s Exploring for the Future program, this study aims to derive porosity, permeability and gas content from both laboratory testing and well log interpretation from machine learning approaches, to improve the Proterozoic shale gas reservoir characterisation. The Proterozoic Lawn Hill Formation was divided into four chemostratigraphic packages. The middle two packages were further divided into seven internal units according to principal component analysis and self-organising map clustering on well logs and inorganic geochemical properties. Artificial neural networks were then applied to interpret the mineral compositions, porosity and permeability from well logs, density and neutron-density crossplot interpretations. Gas content was estimated from the interpreted porosity, gas saturation, total organic carbon and clay contents. Petrophysical interpretation results are summarised for all chemostratigraphic packages and units. Package 2 (1116–1430.1 m) has the highest potential among the four chemostratigraphic packages. P2U1 (1116–1271 m) and P2U3 (1335.5–1430.1 m) units have the most favourable petrophysical properties for organic-rich shales with the average total gas contents of 1.25 cm3/g and 1.30 cm3/g, geometric mean permeability of 4.79 µD and 17.56 µD, and net shale thickness of 54.4 m and 85.3 m, respectively. P3U4 unit (687.9–697.9 m) has high gas content and permeability, with the net shale thickness of 29.1 m. Besides the organic-rich shales, the tight non-organic-rich siltstone and shale reservoirs in package 1 (below 1430.1 m) have average gas saturation of 14% and geometric mean permeability of 1.31 µD, respectively. Published in The APPEA Journal 2023. <b>Citation:</b> Wang Liuqi, Bailey Adam H. E., Grosjean Emmanuelle, Carson Chris, Carr Lidena K., Butcher Grace, Boreham Christopher J., Dewhurst Dave, Esteban Lionel, Southby Chris, Henson Paul A. (2023) Petrophysical interpretation and reservoir characterisation on Proterozoic shales in National Drilling Initiative Carrara 1, Northern Territory. <i>The APPEA Journal</i><b> 63</b>, 230-246. https://doi.org/10.1071/AJ22049

Exploring for the Future (EFTF) is a four-year $100.5 million initiative by the Australian Government conducted by Geoscience Australia in partnership with state and Northern Territory government agencies, CSIRO and universities to provide new geoscientific datasets for frontier regions. As part of this program, Geoscience Australia acquired two new seismic surveys that collectively extend across the South Nicholson Basin (L120 South Nicholson seismic line) and into the Beetaloo Sub-basin of the McArthur Basin (L212 Barkly seismic line). Interpretation of the seismic has resulted in the discovery of new basins that both contain a significant section of presumed Proterozoic strata. Integration of the seismic results with petroleum and mineral systems geochemistry, structural analyses, geochronology, rock properties and a petroleum systems model has expanded the knowledge of the region for energy and mineral resources exploration. These datasets are available through Geoscience Australia’s newly developed Data Discovery Portal, an online platform delivering digital geoscientific information, including seismic locations and cross-section images, and field site and well-based sample data. Specifically for the EFTF Energy project, a petroleum systems framework with supporting organic geochemical data has been built to access source rock, crude oil and natural gas datasets via interactive maps, graphs and analytical tools that enable the user to gain a better and faster understanding of a basin’s petroleum prospectivity. <b>Citation:</b> Henson Paul, Robinson David, Carr Lidena, Edwards Dianne S., MacFarlane Susannah K., Jarrett Amber J. M., Bailey Adam H. E. (2020) Exploring for the Future—a new oil and gas frontier in northern Australia. <i>The APPEA Journal</i><b> 60</b>, 703-711. https://doi.org/10.1071/AJ19080

<div>This report presents the results of petrographic and X-ray Diffraction analysis undertaken by Microanalysis Australia under contract to Geoscience Australia, on rock samples collected from selected drill holes across the Proterozoic Birrindudu Basin and underlying metamorphic basement.</div><div><br></div>

The Exploring for the Future program is an initiative by the Australian Government dedicated to boosting investment in resource exploration in Australia. As part of the Exploring for the Future program, this study aims to improve our understanding of the petroleum resource potential of northern Australia. This data release presents the bulk kerogen kinetics of 21 potential source rocks from the McArthur Basin and the Lawn Hill Platform to understand the rate of hydrocarbon conversion. Kerogen was isolated from bulk rock, and analysed by a Rock-Eval 6 (Vinci Technologies, France) using four different temperature ramps. All sample preparation and analyses were carried out in Geoscience Australia’s in-house laboratories. The results of this study can be used to improve our understanding of the hydrocarbon generative potential of Proterozoic aged source rocks in northern Australia.

<div>Geoscience Australia’s 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.</div><div><br></div><div>The Paleo to Mesoproterozoic Birrindudu Basin is an underexplored frontier basin located in northwestern Northern Territory and northeastern Western Australia. The Birrindudu Basin is a region of focus for the second phase of the EFTF program (2020–2024) as it contains strata of similar age to the prospective McArthur Basin, South Nicholson region and Mount Isa Province, but remains comparatively poorly understood.</div><div><br></div><div>Geoscience Australia have undertaken (via the service provider, FIT, Schlumberger) Fluid Inclusion Petrography and Microthermometry analysis of samples for the drillhole WLMB001B, Birrindudu Basin, located in the northwest Northern Territory (Company reference number MT#FI230004a).</div><div><br></div><div>This eCat Record accompanies the report containing the results of fluid inclusion stratigraphy on this drillhole (eCat record 149178)</div>

The Proterozoic alkaline and related igneous rocks of Australia web map service depicts the spatial representation of the alkaline and related rocks of Proterozoic age.

The Proterozoic alkaline and related igneous rocks of Australia web map service depicts the spatial representation of the alkaline and related rocks of Proterozoic age.