<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>

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.

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 magnetic susceptibility analyses undertaken by Geoscience Australia on selected rock samples to establish their ability to be magnetised in an applied external magnetic field.

<div>NDI Carrara 1 is a 1750 m stratigraphic drill hole completed in 2020 as part of the MinEx CRC National Drilling Initiative (NDI) in collaboration with Geoscience Australia under the Exploring for the Future program and the Northern Territory Geological Survey. It is the first stratigraphic test of the Carrara Sub-basin, a recently discovered depocentre in the South Nicholson region. The drill hole intersected Cambrian and Proterozoic sediments consisting of organic-rich black shales and a thick sequence of interbedded black shales and silty sandstones with hydrocarbon shows. A comprehensive analytical program carried out by Geoscience Australia on the recovered core samples from 283 m to total depth at 1751&nbsp;m provides critical data for calibration of burial and thermal history modelling.</div><div>Using data from this drilling campaign, burial and thermal history modelling was undertaken to provide an estimate of the time-temperature maxima that the sub-basin has experienced, contributing to an understanding of hydrocarbon maturity. Proxy kerogen kinetics are assessed to estimate the petroleum prospectivity of the sub-basin and attempt to understand the timing and nature of hydrocarbon generation. Combined, these newly modelled data provide insights into the resource potential of this frontier Proterozoic hydrocarbon province, delivering foundational data to support explorers across the eastern Northern Territory and northwest Queensland.</div> <b>Citation:</b> Palu Tehani J., Grosjean Emmanuelle, Wang Liuqi, Boreham Christopher J., Bailey Adam H. E. (2023) Thermal history of the Carrara Sub-basin: insights from modelling of the NDI Carrara 1 drill hole. <i>The APPEA Journal</i><b> 63</b>, S263-S268. https://doi.org/10.1071/AJ22048

Geoscience Australia’s Exploring for the Future (EFTF) 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 a low emissions economy, strong 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, is an eight year, $225m investment by the Australian Government. The deep stratigraphic drill hole, NDI Carrara 1 (~1751 m), was completed in December 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 contractor report (FIT - Schlumberger) presents hydrocarbon and aqueous fluid inclusion petrology and data (micro-thermometry, salinities etc.) on four hydrocarbon-bearing calcite veins sampled from NDI Carrara 1 between 762.56-763.60 m depth, (under contract to, and fully funded by, Geoscience Australia as part of the Exploring for the Future program).

<div>This report presents thermal property data (thermal conductivity data, calculated heat production data, and calculated surface heat flow) from the deep (1751 m) stratigraphic drill hole, NDI Carrara 1. Thermal conductivity analyses were undertaken at the University of Melbourne. Heat production values were calculated from existing whole rock geochemical data. Surface heat flow was determined using the laboratory thermal conductivity data together with in situ downhole temperature data collected previously.</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.

NDI Carrara 1 is the first stratigraphic test of the Carrara Sub-basin, a newly discovered depocentre in the South Nicholson region that was identified on newly acquired seismic surveys undertaken as part of the Exploring for the Future program. NDI Carrara 1 intersected a thick sequence of Proterozoic aged siliciclastic and carbonate rocks, which host several intervals of interest to hydrocarbon explorers due to affinities with the known Proterozoic shale gas plays of the Beetaloo Sub-basin and the Lawn Hill Platform. These include two organic-rich black shale sequences and a thick sequence of interbedded black shales and silty-sandstones where numerous hydrocarbon shows are demonstrated. An extensive suite of wireline logs was acquired from total depth to the near surface, and continuous core was recovered through the Proterozoic interval. Geoscience Australia and partners are undertaking an extensive program of analytical work to understand the depositional, structural, and diagenetic history of the sediments intersected by NDI Carrara 1, alongside their resource potential. This study characterises petrophysical and geomechanical properties of the Proterozoic interval of NDI Carrara 1 through interpretation of wireline logging data and integration of some of this interpretation with results of geochemical analyses. High interpreted TOC content and a high calculated net shale ratio, alongside high estimated hydrocarbon saturations suggest a high potential for unconventional gas resources in the Proterozoic shale intervals of the Carrara Sub-basin; an assessment supported by gas peaks, particularly methane, measured in mud-logging gas profiles during drilling. Shale brittleness indices and interpreted present-day stresses highlight areas that are likely to be favourable for unconventional gas techniques and which may form attractive shale gas plays. 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/presented to the 2022 Central Australian Basins Symposium IV (CABS) 29-30 August (https://agentur.eventsair.com/cabsiv/)

<div>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 stratigraphic 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) 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 Georgina Basin carbonates.&nbsp;</div><div>Geoscience Australia has undertaken a range of investigations on the lithology, stratigraphy and geotechnical properties of NDI Carrara 1 as well as undertaking a range of analyses of about 500 physical samples recovered through the entire core. Analyses included geochronology, isotope studies, mineralogy, inorganic and organic geochemistry, petrophysics, geomechanics, thermal maturity and petroleum systems investigations.</div><div>Rock-Eval pyrolysis raw data undertaken by Geoscience Australia were reported in Butcher et al. (2021) on selected rock samples to establish their total organic carbon content, hydrocarbon-generating potential and thermal maturity. Interpretation of the Rock-Eval pyrolysis data concluded that a large portion of rocks within the Proterozoic section displayed unreliable Tmax values due to poorly defined S2 peaks resulting from high thermal maturity and low hydrogen content. In order to obtain more reliable Tmax values, Rock-Eval pyrolysis of selected isolated kerogens, where organic matter is concentrated and mineral matrix effects are removed, were conducted and the resulting data are presented in this report.&nbsp;</div><div><br></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.