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  • This web service provides access to groundwater raster products for the Upper Burdekin region, including: inferred relative groundwater recharge potential derived from weightings assigned to qualitative estimates of relative permeability based on mapped soil type and surface geology; Normalised Difference Vegetation Index (NDVI) used to map vegetation with potential access to groundwater in the basalt provinces, and; base surfaces of basalt inferred from sparse available data.

  • The Layered Geology of Australia web map service is a seamless national coverage of Australia’s surface and subsurface geology. Geology concealed under younger cover units are mapped by effectively removing the overlying stratigraphy (Liu et al., 2015). This dataset is a layered product and comprises five chronostratigraphic time slices: Cenozoic, Mesozoic, Paleozoic, Neoproterozoic, and Pre-Neoproterozoic. As an example, the Mesozoic time slice (or layer) shows Mesozoic age geology that would be present if all Cenozoic units were removed. The Pre-Neoproterozoic time slice shows what would be visible if all Neoproterozoic, Paleozoic, Mesozoic, and Cenozoic units were removed. The Cenozoic time slice layer for the national dataset was extracted from Raymond et al., 2012. Surface Geology of Australia, 1:1 000 000 scale, 2012 edition. Geoscience Australia, Canberra.

  • This web service delivers metadata for onshore active and passive seismic surveys conducted across the Australian continent by Geoscience Australia and its collaborative partners. For active seismic this metadata includes survey header data, line location and positional information, and the energy source type and parameters used to acquire the seismic line data. For passive seismic this metadata includes information about station name and location, start and end dates, operators and instruments. The metadata are maintained in Geoscience Australia's onshore active seismic and passive seismic database, which is being added to as new surveys are undertaken. Links to datasets, reports and other publications for the seismic surveys are provided in the metadata.

  • The Exploring for the Future program is an initiative by the Australian Government dedicated to boosting investment in resource exploration in Australia. The initial phase of this program led by Geoscience Australia focussed on northern Australia to gather new data and information about the potential mineral, energy and groundwater resources concealed beneath the surface. The northern Lawn Hill Platform is an intracratonic poly-phased history region of Paleoproterozoic to Mesoproterozic age consisting of mixed carbonates, siliciclastics and volcanics. It is considered a frontier basin with very little petroleum exploration to date, but with renewed interest in shale and tight gas, that may present new exploration opportunities. An understanding of the geochemistry of the sedimentary units, including the organic richness, hydrocarbon-generating potential and thermal maturity, is therefore an important characteristic needed to understand the resource potential of the region. As part of this program, Rock-Eval pyrolysis analyses were undertaken by Geoscience Australia on selected rock samples from 2 wells of the northern Lawn Hill Platform.

  • This report presents key results from the Howard East project conducted as part of Exploring for the Future (EFTF), an Australian Government funded geoscience data and information acquisition program. The four-year (2016–20) program focused on better understanding the potential mineral, energy and groundwater resources in northern Australia. Groundwater is an essential part of Darwin’s water supply and is sourced from the Koolpinyah Dolostone Aquifer (KDA) at the Howard East Borefield (HEB) and McMinns Borefield, which are ~25 km to 30 km southeast of Darwin. Previous work suggests that electrical conductivity anomalies observed in airborne electromagnetic (AEM) data within 5 km of HEB may be caused by saline groundwater within the KDA that is separated from HEB by dykes and other geological features that effectively compartmentalise the aquifer (Fell-Smith & Sumner, 2011; Tan et al., 2012). Nevertheless, concerns have grown that increased groundwater use may result in migration of saline groundwater toward HEB, which could compromise the groundwater resource. We collected groundwater chemistry including isotopes, time-series groundwater salinity, AEM, and induction and gamma data to better understand the complexities of the KDA. We show that groundwater in the KDA typically has a fresh Mg-Ca-HCO3 type composition, as is expected for a dolomitic aquifer. Highly saline Na-Cl type groundwater with a composition similar to seawater exists at some locations as well as groundwater with a mixed composition. These findings confirm previous interpretations for the area (e.g. Fell-Smith & Sumner, 2011). We sampled saline groundwater on the opposite side of two dolerite dykes to HEB to its northeast. Age dating results for this sample cannot be used to determine whether this saline groundwater represents relict seawater or whether groundwater at this site is in hydraulic connection with the modern ocean. Our groundwater chemistry results also show that saline intrusion is occurring northwest of HEB. AEM data were collected to better characterise geological and hydrogeological features in the area. Estimates of bulk conductivity of the subsurface were derived by inverting AEM data using both deterministic and stochastic methods. Using these AEM inversions and other hydrogeological information, we characterised high-conductivity anomalies within 5 km of HEB and the upper surface of unweathered dolerite in the two dykes northeast of HEB. We interpreted conductivity anomalies as pyritic shales, although drilling is required to investigate the salinity of groundwater in the KDA in this area. Where we were able to resolve the upper surface of unweathered material in the two dykes using the AEM, we found that it commonly occurs below sea level. Characterising the geometry of these dykes will aid in assessing their role in aquifer compartmentalisation. Our findings contribute to building a robust conceptual understanding of the KDA and will guide future investigations into the groundwater system. A number of other products exist for the EFTF Howard East project. The findings of this report are integrated with hydrodynamic analyses undertaken by Woltmann (in prep.) and reported in Haiblen et al. (2020). Hydrochemistry data presented here are contained in McGrath-Cohen et al. (2020), water level and salinity monitoring data can be found in Turner et al. (2020), AEM data are in Ray et al. (2020b), and induction and gamma data are in Tan et al. (2020).

  • Long-period 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, the identification of which is an important element of several mineral system models. Given the importance of these data, governments and academia have united under the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP) to collect long-period MT data across the continent on a ~55 km-spaced grid. Here, we use AusLAMP data to demonstrate the MT method as a regional-scale tool to identify and select prospective areas for mineral exploration undercover. We focus on the region between Tennant Creek in the Northern Territory and east of Mount Isa in Queensland. Our results image major conductive structures up to 150 km deep in the lithosphere, such as the Carpentaria Conductivity Anomaly east of Mount Isa. This anomaly is a significant lithospheric-scale conductivity structure that shows spatial correlations with a major suture zone and known iron oxide–copper–gold deposits. Our results also identify similar features in several under-explored areas that are now considered to be prospective for mineral discovery. These observations provide a powerful means of selecting frontier regions for mineral exploration undercover.. <b>Citation:</b> Duan, J., Kyi, D., Jiang, W. and Costelloe, M., 2020. AusLAMP: imaging the Australian lithosphere for resource potential, an example from northern Australia. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A. and Slatter, E. (eds.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1–4.

  • The Source Rock and Fluids Atlas delivery and publication services provide up-to-date information on petroleum (organic) geochemical and geological data from Geoscience Australia's Organic Geochemistry Database (ORGCHEM). The sample data provides the spatial distribution of petroleum source rocks and their derived fluids (natural gas and crude oil) from boreholes and field sites in onshore and offshore Australian basins. The services provide characterisation of source rocks through the visualisation of Pyrolysis, Organic Petrology (Maceral Groups, Maceral Reflectance) and Organoclast Maturity data. The services also provide molecular and isotopic characterisation of source rocks and petroleum through the visualisation of Bulk, Whole Oil GC, Gas, Compound-Specific Isotopic Analyses (CSIA) and Gas Chromatography-Mass Spectrometry (GCMS) data tables. Interpretation of these data enables the characterisation of petroleum source rocks and identification of their derived petroleum fluids that comprise two key elements of petroleum systems analysis. The composition of petroleum determines whether or not it can be an economic commodity and if other processes (e.g. CO2 removal and sequestration; cryogenic liquefaction of LNG) are required for development.

  • Exploring for the Future is a four-year $100.5 million programme to unveil new resource opportunities in Northern Australia and parts of South Australia. It is being conducted by Geoscience Australia in partnership with state and Northern Territory government agencies, CSIRO, and universities. This initiative, which is due for completion in 2020–2021, has started to deliver a suite of new products to help unveil new resource opportunities in Northern Australia. The programme has three inter-related elements: minerals, energy and groundwater, which collectively aims to: • provide baseline pre-competitive geoscience data to inform and encourage government, industry and community decision making about sustainable resources management to improve Northern Australia’s economic development • attract investment in resource exploration to Northern Australia • deliver an assessment of groundwater resources for irrigated agriculture and community water supplies as well as for mineral and energy development; and an assessment of the potential impacts of those developments. The minerals-focussed projects have been designed with a three-fold programme logic (Figure 1): 1) Northern Australia-wide projects, 2) focussed integrated studies, and 3) generic innovation and method development. The minerals-focussed project activities address a number of the highest and high priority themes identified by the mineral exploration industry in the UNCOVER Roadmap. 1) Northern Australia-wide projects This work programme will develop and use innovative tools and techniques to collect semi-continental a) geological, b) geochemical, and c) geophysical data on an unprecedented scale. The commencement of these projects is focussed on the region between Tennant Creek and Mt Isa (TISA). a) Geological projects Because one person’s cover is another person’s basement, a Northern Australia-wide series of time-based geological maps are being prepared. Building from the national 1:1 M scale Surface Geology Map of Australia, the Cenozoic, Mesozoic, Palaeozoic and Neoproterozoic layers will be successively removed to reveal a series of ‘solid geology’ maps at 1:1M scale. These maps will form the basis for subsequent 3D models and resource assessments. Extensive use is being made of national-scale potential field geophysical data and existing drillhole data. This has the combined effect of calibrating the geological interpretation of the geophysics with known rocks and attributing the interfaces with their actual depth (from drilling or geophysical estimates). Resultant 3D data are being stored in a new database called Estimates of Geological and Geophysical Surfaces (EGGS); this is a national repository for depth-determined geological information from any method (drilling or geophysical estimate). The EGGS’ database will form the depth-control points from which new 3D surfaces will be constructed and imported into a 3D geological model along with uncertainty. A new peak metamorphic map of Australia is also in production, with a subset available for Northern Australia in the first phase. This map is a compilation of quantitative and qualitative estimates of metamorphic conditions across Australia. The maps will provide important constraints on the crustal exhumation and (mineral) preservation history as well as thermo-barometric evolution of Australia. b) Geochemical projects An atlas of the surface of Northern Australia, as a subset of the national atlas, is in preparation. Geoscience Australia has time-series LANDSAT data from NASA extending back into the 1980s. Each pixel from each scene has been organised in Digital Earth Australia (DEA) so the archive can be ‘data-mined’ to extract pixels with the least vegetation and cloud-cover effects. Products of this work will be a new national Bare Earth image along with iron oxide, silica and clay mineral maps of the surface at 25 m resolution. The European Space Agency’s Sentinel 2 satellite system provides global coverage of multispectral earth-observation data at 10 m resolution from these data. A new cloud-free seamless Sentinel 2 national map will be produced at 10 m resolution. A suite of new machine learning codes has been produced in collaboration with DATA61. These codes are being deployed on the national whole rock and surface geochemical datasets to produce national surface maps of the major elements. An isotopic atlas for northern Australia is being prepared, consisting of a suite of map layers including Sm–Nd, Lu–Hf, U–Pb, Ar–Ar and Pb–Pb; it will be delivered in GIS form, and draped on the aforementioned 3D surfaces. In addition, selected age dating of geological units through U–Pb SHRIMP geochronology and various other dating techniques for direct dating of key mineral deposits are being undertaken. c) Geophysical projects The world’s largest airborne electromagnetic (AusAEM) survey and the most extensive long-period magnetotelluric (AusLAMP) survey are well underway. At the time of writing (February 2018), 20 600 line-km of the 60,000 planned AusAEM data have been flown and 155 new AusLAMP stations have been acquired. In addition, a new seismic tomographic velocity model will be constructed from historical earthquake data; these data form the basis of the Australia-wide AusARRAY project. Gravity data are being infilled at higher resolutions in areas where station spacing is >4 km using a mix of ground and airborne gravity and airborne gravity gradiometry. 2) Focused Integrated Studies (TISA) The region between Tennant Creek and Mt Isa (TISA) is the initial focus of all the above-mentioned activities plus a series of additional projects. This vast under cover region lies between the great mining centres of Tennant Creek (Cu, Au) and Mt Isa (Cu, Pb, Zn, Ag). The thickness of cover is variable and the underlying ‘basement’ geology is poorly known. The region lies at a key junction in Australian geology, with north-south striking domains in the east joining east-west and northwest-southeast striking domains in the west. The region showed unexplained base metal anomalism in the National Geochemical Survey of Australia (NGSA) and at depth, it has variable seismic velocity and Moho depths. The programme has collected 782 surface geochemical and 118 groundwater samples to augment the broad-spaced NGSA dataset; laboratory results are being modelled with the first products due for release in March 2018. The AusARRAY project deployed 120 passive seismic recorders that will remain in the TISA region until later this year. Two more deployments are expected in the life of the programme at locations to be confirmed. A total of 2724 ground gravity stations were collected; the data was released in 2017. A total of 1100 km of deep seismic reflection data have been acquired and processed (see Henson this volume), with processed data to be released in March 2018, and interpretation products to follow. The aim of focusing the activities into one region is to provide the best possible suite of data that will be integrated into an assessment of the undercover mineral potential of the TISA region. This assessment and the geological and mineral systems interpretations of the above data will be tested by a stratigraphic drilling programme in 2019. Assessments are underway for basin-hosted base metals (Cu, Pb, Zn) and for iron-oxide-copper-gold mineral systems. The basin assessment will draw on well-established petroleum systems approaches and apply them to these mineral systems. When the programme is complete, the TISA region will arguably be the best imaged and understood piece of lithosphere on the planet. 3) Innovation and Method Development To complement data acquisition, new big data management and data analytical methods, tools and platforms are being developed to maximise data value. Strategic collaborations have been established with world-leading experts at Australian universities and DATA61 to develop a suite of new geoscience-relevant computer codes and products that will be released in open source repositories (GitHub) and be incorporated into the Australian National Virtual Geophysical Laboratory (ANVGL). Given the vast range of activities being conducted, many of which are novel, effort is being made to share the generic lessons. This includes publishing software codes and standard operating procedures as well as developing an Explorer’s Guide for the TISA region that will have generic applicability elsewhere. Particular effort is being made to transfer knowledge and receive feedback from industry through a series of workshops that commenced in 2017. Conclusions Exploring for the Future, an exciting initiative in collaboration with state and NT partners, will: • Assist in securing an ongoing pipeline of new discoveries and help maintain Australia’s position as a major global mineral and energy exporter. • Determine the location, quantity and quality of groundwater resources to inform water management options, including infrastructure development and water banking. • Benefit the Mining Equipment, Technology and Services (METS) sector by drawing on private sector expertise in undertaking data acquisition and analysis.

  • The Upper Burdekin Basalt extents web service delivers province extents, detailed geology, spring locations and inferred regional groundwater contours for the formations of the Nulla and McBride Basalts. This work has been carried out as part of Geoscience Australia's Exploring for the Future program.

  • The Upper Burdekin Basalt extents web service delivers province extents, detailed geology, spring locations and inferred regional groundwater contours for the formations of the Nulla and McBride Basalts. This work has been carried out as part of Geoscience Australia's Exploring for the Future program.