<div>A PowerPoint presentation given by Chief of Minerals, Energy and Groundwater Division Dr Andrew Heap at NT Resources Week 2023. </div><div><br></div><div>This presentation had the theme of 'Precompetitive geoscience - Uncovering our critical minerals potential.'</div>

Magnetotelluric (MT) data allow geoscientists to investigate the link between mineralisation and lithospheric-scale features and processes. In particular, the highly conductive structures imaged by MT data appear to map the pathways of large-scale palaeo-fluid migration, which is an important element of several mineral systems. New data were collected as part of the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) under Geoscience Australia Exploring for the Future (EFTF) program in northern Australian. We use this dataset to demonstrate that the MT method is a valuable tool for mapping lithospheric-scale features and for selecting prospective areas for mineral exploration. Our results image a number of major conductive structures at depths up to ~200 km or deeper in the survey region, for example, the Carpentaria Conductivity Anomaly in east of Mount Isa; and the Tanami Conductive Anomaly along the Willowra Suture Zone. These significant anomalies are lithospheric- scale highly conductive structures, and show spatial correlations with major suture zones and known mineral deposits. These results provide important first-order information for lithospheric architecture and possible large footprint of mineral systems. Large-scale crustal/mantle conductivity anomalies mapping fluid pathways associated with major sutures/faults may have implications for mineral potential. These results provide evidence that some mineralisation occurs at the gradient of or over highly conductive structures at lower crustal and lithospheric mantle depths. These observations provide a powerful means of highlighting greenfields for mineral exploration in under-explored and covered regions.

<div>Alkaline igneous and related rocks are recognised as a significant source of the critical minerals essential for Australia’s transition to net-zero. Understanding these small but economically significant group of poorly mapped rocks is essential for identifying their resource potential. The Australian Alkaline Rocks Atlas aims to capture all known occurrences of these volumetrically minor, but important, igneous rocks in a national compilation, to aid understanding of their composition, distribution and age at the continental scale. The Atlas, comprises five, stand-alone data packages covering the Archean, Proterozoic, Paleozoic, Mesozoic and Cenozoic eras. Each data package includes a GIS database and detailed accompanying report that informs alkaline rock nomenclature, classification procedures, individual units and their grouping into alkaline provinces based on common age, characteristics and inferred genesis. The Alkaline Rocks Atlas will form a foundation for more expansive research on related mineral systems and their corresponding economic potential being undertaken as part of the EFTF program. To illustrate the use of the Alkaline Rocks Atlas, a mineral potential assessment using a subset of the Atlas has been undertaken for carbonatite-related rare earth element mineral systems that aims to support mineral exploration and land-use decision making that aims to support mineral exploration and land-use decision making.</div>

<div>Poster for the Specialist Group in Geochemistry, Mineralogy & Petrology (SGGMP) conference in Yallingup WA in November 2022.</div><div><br></div>This Poster was presented to the 2022 Specialist Group in Geochemistry, Mineralogy and Petrology (SGGMP) Conference 7-11 November (https://gsasggmp.wixsite.com/home/biennial-conference-2021)

<div>Reliable water availability is critical to supporting communities and industries such as mining, agriculture and tourism. In remote and arid areas such as in the Officer – Musgrave region of central Australia, groundwater is the only viable source of water for human and environmental use. Groundwater systems in remote regions such as the Musgrave Province are poorly understood due to sparse geoscientific data and few detailed scientific investigations. The Musgrave palaeovalley module will improve palaeovalley groundwater system understanding in the Musgrave Province and adjacent basins to identify potential water sources for communities in the region. This report summarises the state of knowledge for the region on the landscape, population, water use, geology and groundwater systems. An analysis of the current and potential future water needs under different development scenarios captures information on how water is used in an area covering three jurisdictions and several potentially competing land uses.</div><div>The Musgrave Palaeovalley study area is generally flat, low-lying desert country. The Musgrave, Petermann, Mann and Warburton ranges in the centre of the area are a significant change in elevation and surface materials, comprising rocky hills, slopes and mountains with up to 800&nbsp;m of relief above the sand plains. Vegetation is generally bare or sparse, with isolated pockets of grassy or woody shrub lands. Soils are typically Tenosols, Rudosols and Kandosols.</div><div><br></div><div>There are four main hydrogeological systems in the study area. These are the fractured and basement rocks, local Quaternary sediments regional sedimentary basins and palaeovalley aquifers. These systems are likely to be hydraulically connected. Within palaeovalleys, three main hydrostratigraphic units occur. The upper Garford Formation is a sandy unconfined aquifer with a clay rich base (lower Garford Formation) which acts as a partial aquitard where present. The Pidinga Formation represents a coarser sandy or gravelly channel base, which is partly confined by the lower Garford Formation aquitard. The aquifers are likely to be hydraulically connected on a regional scale. Further to the west, equivalent units are identified and named in palaeovalley systems on the Yilgarn Craton. </div><div><br></div><div>Groundwater is recharged by episodic, high-intensity rainfall events and mostly discharges via evapotranspiration. Recharge is higher around the ranges, and lower over the flatter sand plains. Palaeovalley aquifers likely receive some groundwater inflow from underlying basin systems and fractured rock systems. Regional groundwater movement is topographically controlled, moving from the ranges towards surrounding areas of lower elevation. In some palaeovalleys groundwater discharges at playa lakes. Water table gradients are very low. More groundwater isotope and tracer data is required to understand potential connectivity between basin, fractured rock and palaeovalley systems.</div><div>Groundwater quality is brackish to saline, although pockets of fresher groundwater occur close to recharge areas and within the deeper and coarse-grained Garford Formation. Groundwater resources generally require treatment prior to use Most groundwater in the region is suitable for stock use. </div><div><br></div><div>Existing palaeovalley mapping is restricted to inferring extents based on landscape position and mapped surface materials. Utilising higher resolution digital elevation models and more recently acquired remotely sensed data will refine mapped palaeovalley extents. Improving the modelling of the distribution and depth of palaeovalleys in greater detail across the region is best aided through interpretation of airborne electromagnetic (AEM) data.</div><div>Based on the successes of integrating AEM with other geoscientific data in South Australia, we have acquired 25,109 line km of new AEM across the WA and NT parts of our study area. We will integrate this data with reprocessed and inverted publicly available AEM data, existing borehole information, existing and newly acquired hydrochemical data, and new surface magnetic resonance data to model the three dimensional distribution of palaeovalleys in the study area. We will use these models and data as the basis for conceptualising the hydrogeology of the palaeovalley systems, and provide information back to local communities and decision-makers to inform water management decisions. The data will also provide valuable precompetitive information for future economic development in the region.</div><div><br></div>

<div>This was the last of five presentations held on 31 July 2023 as part of the National Groundwater Systems Workshop. Towards developing a 3D hydrogeological framework for Australia: A common chronostratigraphic framework for aquifers&nbsp;</div><div><br></div>

This data package provides seismic interpretations that have been generated in support of the energy resource assessments under the Australia’s Future Energy Resources (AFER) project. Explanatory notes are also included. The AFER project is part of Geoscience Australia’s Exploring for the Future (EFTF) Program—an eight year, $225 million Australian Government funded geoscience data and precompetitive information acquisition program 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, Geoscience Australia is building a national picture of Australia’s geology and resource potential. This will help support a strong economy, resilient society and sustainable environment for the benefit of all Australians. The EFTF program is supporting Australia’s transition to a low emissions economy, industry and agriculture sectors, as well as economic opportunities and social benefits for Australia’s regional and remote communities. Further details are available at http://www.ga.gov.au/eftf. The seismic interpretations build on the recently published interpretations by Szczepaniak et al. (2023) by providing updated interpretations in the AFER Project area for the Top Cadna-owie (CC10) and Top Pre-Permian (ZU) horizons, as well as interpretations for 13 other horizons that define the tops of play intervals being assessed for their energy resource potential (Figure 1). Seismic interpretations for the AFER Project are constrained by play interval tops picked on well logs that have been tied to the seismic profiles using time-depth data from well completion reports. The Pedirka and Western Eromanga basins are underexplored and contain relatively sparse seismic and petroleum well data. The AFER Project has interpreted play interval tops in 41 wells, 12 seismic horizons (Top Cadna-owie and underlying horizons) on 238 seismic lines (9,340 line kilometres), and all 15 horizons on 77 recently reprocessed seismic lines (3,370 line kilometres; Figure 2). Note that it has only been possible to interpret the Top Mackunda-Winton, Top Toolebuc-Allaru and Top Wallumbilla horizons on the reprocessed seismic lines as these are the only data that provide sufficient resolution in the shallow stratigraphic section to confidently interpret seismic horizons above the Top Cadna-owie seismic marker. The seismic interpretations are provided as point data files for 15 horizons, and have been used to constrain the zero edges for gross-depositional environment maps in Bradshaw et al. (2023) and to produce depth-structure and isochore maps for each of the 14 play intervals in Iwanec et al. (2023). The data package includes the following datasets: 1) Seismic interpretation point file data in two-way-time for up to 15 horizons using newly reprocessed seismic data and a selection of publicly available seismic lines (Appendix A). 2) Geographical layers for the seismic lines used to interpret the top Cadna-owie and underlying horizons (Cadnaowie_to_TopPrePermian_Interpretation.shp), and the set of reprocessed lines used to interpret all 15 seismic horizons (All_Horizons_Interpretation.shp; Appendix B). These seismic interpretations are being used to support the AFER Project’s play-based energy resource assessments in the Pedirka and Western Eromanga basins.

<div>Geoscience Australia’s Exploring for the Future (EFTF) program is a multi-year Australian Government initiative, led by Geoscience Australia in partnership with State and Territory governments. The 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 information, 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 EFTF program, which commenced in 2016, is an eight year, $225 million investment by the Australian Government.</div><div><br></div><div>This report presents the results of Grains with Oil Inclusions (GOI™) and Frequency of Oil Inclusions (FOI™) on rock samples from three selected drill holes across the Birrindudu Basin. Forty-five samples were obtained from drill holes WLMB001B, ANT003 and 99VRNTGSDD1. GOI™ and FOI™ was conducted on sedimentary and carbonate vein lithologies to investigate the potential presence of oil inclusions. Oil inclusions were recorded in samples taken from drill holes WLMB001B and ANT003, but not 99VRNTGSDD1. Analysis was undertaken by CSIRO under contract to Geoscience Australia.</div>

<div>This data package provides depth and isochore maps generated in support of the energy resource assessments under the Australia’s Future Energy Resources (AFER) project. Explanatory notes are also included.</div><div><br></div><div>The AFER project is part of Geoscience Australia’s Exploring for the Future (EFTF) Program—an eight year, $225 million Australian Government funded geoscience data and precompetitive information acquisition program 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, Geoscience Australia is building a national picture of Australia’s geology and resource potential. This will help support a strong economy, resilient society and sustainable environment for the benefit of all Australians. The EFTF program is supporting Australia’s transition to a low emissions economy, industry and agriculture sectors, as well as economic opportunities and social benefits for Australia’s regional and remote communities. Further details are available at http://www.ga.gov.au/eftf.</div><div><br></div><div>The depth and isochore maps are products of depth conversion and spatial mapping seismic interpretations by Szczepaniak et al. (2023) and Bradshaw et al. (2023) which interpreted 15 regional surfaces. These surfaces represent the top of play intervals being assessed for their energy resource potential (Figure 1). These seismic datasets were completed by play interval well tops by Bradshaw et al. (in prep), gross depositional environment maps, zero edge maps by Bradshaw et al. (in prep), geological outcrop data as well as additional borehole data from Geoscience Australia’s stratigraphic units database.</div><div><br></div><div>Depth and isochore mapping were undertaken in two to interactive phases; </div><div><br></div><div>1.&nbsp;&nbsp;&nbsp;&nbsp;A Model Framework Construction Phase – In this initial phase, the seismic interpretation was depth converted and then gridded with other regional datasets. </div><div><br></div><div>2.&nbsp;&nbsp;&nbsp;&nbsp;A Model Refinement and QC Phase – This phase focused on refining the model and ensuring quality control. Isochores were generated from the depth maps created in the previous phase. Smoothing and trend modelling techniques were then applied to the isochore to provide additional geological control data in areas with limited information and to remove erroneous gridding artefacts.&nbsp;</div><div><br></div><div>The final depth maps were derived from isochores, constructing surfaces both upward and downward from the CU10_Cadna-owie surface, identified as the most data-constrained surface within the project area. This process, utilizing isochores for depth map generation, honours all the available well and zero edge data while also conforming to the original seismic interpretation.</div><div><br></div><div>This data package includes the following datasets: </div><div><br></div><div>1)&nbsp;&nbsp;&nbsp;Depth maps, grids and point datasets measured in meters below Australian Height Datum (AHD, for 15 regional surfaces (Appendix A). </div><div>2)&nbsp;&nbsp;&nbsp;Isochore maps, grids and point datasets measured in meters, representing 14 surfaces/play internals (Appendix B).</div><div>&nbsp;</div><div>These depth and isochore maps are being used to support the AFER Project’s play-based energy resource assessments in the Pedirka and western Eromanga basins, and will help to support future updates of 3D geological and hydrogeological models for the Great Artesian Basin by Geoscience Australia.</div><div><br></div>

This report presents groundwater level information collected during Geoscience Australia’s Musgrave Palaeovalley Project. The Musgrave Palaeovalley Project was conducted as part of Exploring for the Future (EFTF), an Australian Government funded geoscience data and information acquisition program. The eight-year, $225 million program aims to deliver new geoscience data and knowledge to inform decision-making by government, community, and industry on the sustainable development of Australia's mineral, energy, and groundwater resources.</div><div>Groundwater level data was collected during two hydrogeochemical surveys undertaken in March and May 2023 based around the remote communities of Warburton, Kaltukatjara, Wanarn, Blackstone and Jameson in Western Australia and the Northern Territory. Sixteen bores were measured for their groundwater levels. The results are contained herein and within the attached CSV file.