Geochemical surveys deliver fundamental data, information and knowledge about the concentration and spatial distribution of chemical elements, isotopes and compounds in the natural environment. Typically near-surface sampling media, such as soil, sediment, outcropping rocks and stream or groundwater, are used. The application of such datasets to fields such as mineral exploration, environmental management, and geomedicine has been widely documented. In this presentation I reflect on a sabbatical experience with the Australian Federal Police (AFP) in 2017-2018 that allowed me to extend the interpretation of geochemical survey data beyond these established applications. In particular, with my collaborators we explore ways in which geochemical survey data and maps can be used to indicate the provenance of an evidentiary sample collected at a crime scene or obtained for instance from items belonging to a suspect intercepted at border entry. Because soils are extremely diverse mineralogically, geochemically and biologically, it should theoretically be possible to exclude very large swathes of territory (>90%) from further provenancing investigation using soil data. In a collaboration between Geoscience Australia (GA), the AFP and the University of Canberra (UC), a recent geochemical survey of the urban/suburban Canberra region in southeastern Australia is being used as a testbed for developing different approaches to forensic applications of geochemical surveys. A predictive soil provenancing method at the national scale was also developed and tested for application where no actual detailed, fit-for-purpose geochemical survey data exist. Over the next few years, GA, AFP and UC are collaborating with Flinders University to add biome data from soil and soil-derived dust to further improve the provenancing technique. This Abstract was presented at the 2021 Goldschmidt Conference (https://conf.goldschmidt.info/goldschmidt/2021/meetingapp.cgi)

We collected 38 groundwater and two surface water samples in the semi-arid Lake Woods region of the Northern Territory to better understand the hydrogeochemistry of this system, which straddles the Wiso, Tennant Creek and Georgina geological regions. Lake Woods is presently a losing waterbody feeding the underlying groundwater system. The main aquifers comprise mainly carbonate (limestone and dolostone), siliciclastic (sandstone and siltstone) and evaporitic units. The water composition was determined in terms of bulk properties (pH, electrical conductivity, temperature, dissolved oxygen, redox potential), 40 major, minor and trace elements as well as six isotopes (δ18Owater, δ2Hwater, δ13CDIC, δ34SSO4=, δ18OSO4=, 87Sr/86Sr). The groundwater is recharged through infiltration in the catchment from monsoonal rainfall (annual average rainfall ~600 mm) and runoff. It evolves geochemically mainly through evapotranspiration and water–mineral interaction (dissolution of carbonates, silicates, and to a lesser extent sulfates). The two surface waters (one from the main creek feeding the lake, the other from the lake itself) are extraordinarily enriched in 18O and 2H isotopes (δ18O of +10.9 and +16.4 ‰ VSMOW, and δ2H of +41 and +93 ‰ VSMOW, respectively), which is interpreted to reflect evaporation during the dry season (annual average evaporation ~3000 mm) under low humidity conditions (annual average relative humidity ~40 %). This interpretation is supported by modelling results. The potassium (K) relative enrichment (K/Cl mass ratio over 50 times that of sea water) is similar to that observed in salt-lake systems worldwide that are prospective for potash resources. Potassium enrichment is believed to derive partly from dust during atmospheric transport/deposition, but mostly from weathering of K-silicates in the aquifer materials (and possibly underlying formations). Further studies of Australian salt-lake systems are required to reach evidence-based conclusions on their mineral potential for potash, lithium, boron and other low-temperature mineral system commodities such as uranium. <b>Citation:</b> P. de Caritat, E. N. Bastrakov, S. Jaireth, P. M. English, J. D. A. Clarke, T. P. Mernagh, A. S. Wygralak, H. E. Dulfer & J. Trafford (2019) Groundwater geochemistry, hydrogeology and potash mineral potential of the Lake Woods region, Northern Territory, Australia, <i>Australian Journal of Earth Sciences</i>, 66:3, 411-430, DOI: 10.1080/08120099.2018.1543208

Australia has a low seismicity when compared to countries located along tectonic plate boundaries. Seismic risk, however, is the combination of hazard, community exposure and infrastructure vulnerability. The legacy of older unreinforced masonry buildings is a particular subset of the built environment that may contribute disproportionately to community risk. Documented information on the damage to buildings caused by earthquake events is fundamental to understanding this risk. The Earthquake Earlier this year on the 20th April a magnitude 5.0 (ML) earthquake shook the Western Australian goldfields town of Kalgoorlie. The earthquake was shallow (1.7 km) and was located immediately south of the business district of the Kalgoorlie suburb of Boulder (refer Figure 1). The severity of ground motion was found to vary markedly across the town with the older masonry building stock in Boulder experiencing a greater intensity of shaking than the corresponding building age group in the Kalgoorlie business district 4 km away. The event has provided the best opportunity to examine the earthquake vulnerability of Australian buildings since the Newcastle Earthquake of the 28th December 1989, over twenty years prior. The Survey Following the earthquake Geoscience Australia (GA) arranged a staged collaborative survey that would capture information from which vulnerability knowledge could be derived.

This resource includes backscatter data for Arafura Marine Park (Arafura Sea) collected by Geoscience Australia (GA) and the Australian Institute of Marine Science during the period 2 – 15 November 2020 on the RV Solander. The survey was undertaken as a collaborative project funded through the National Environmental Science Program Marine Biodiversity Hub, with co-investment by GA and AIMS. The purpose of the project was to build baseline information for benthic habitats in Arafura Marine Park that will support ongoing environmental monitoring within the North Marine Park Network as part of the 10-year management plan (2018-2028). Data acquisition for the project included multibeam bathymetry and backscatter for two areas (Money Shoal and Pillar Bank), seabed samples and underwater imagery of benthic communities and demersal fish. This backscatter dataset contains two 32-bit geotiff files of the backscatter mosaic for two survey areas produced from the processed EM2040C Dual Head system using the CMST-GA MB Process v15.04.04.0 (x64) toolbox software co-developed by the Centre for Marine Science and Technology at Curtin University and Geoscience Australia. A detailed report on the survey is provided in: Picard, K. Stowar, M., Roberts, N., Siwabessy, J., Abdul Wahab, M.A., Galaiduk, R., Miller, K., Nichol, S. 2021. Arafura Marine Park Post Survey Report. Report to the National Environmental Science Program, Marine Biodiversity Hub (https://www.nespmarine.edu.au/node/4505).

This resource includes seabed backscatter data for South-west Corner Marine Park collected by Geoscience Australia during the periods 9 – 12 March 2020 and 27 January – 16 February 2021 on the charter vessel Santosha. The survey was undertaken as a collaborative project with the University of Western Australia, the University of Tasmania and the Australian Centre for Field Robotics (University of Sydney) and funded through the National Environmental Science Program Marine Biodiversity Hub, with co-investment by all partners and the Director of National Parks. The purpose of the project was to build baseline information for benthic habitats on the continental shelf in the marine park that will support ongoing environmental monitoring within the South-west Marine Park Network as part of the 10-year management plan (2018-2028). Data acquisition for the project included multibeam bathymetry and backscatter for an area covering 330 km^2 offshore from Cape Naturaliste to Cape Leeuwin coast, with underwater imagery of benthic communities and demersal fish collected by University of Western Australia on separate field deployments. This backscatter dataset contains a 4 m resolution 32-bit geotiff file of the survey area produced from the processed Kongsberg EM2040C multibeam sonar system data using the CMST-GA MB Process v15.04.04.0 (.64) toolbox software co-developed by the Centre for Marine Science and Technology at Curtin University and Geoscience Australia. For further information see: Giraldo-Ospina, A. et al., 2021. South-west Corner Marine Park Post Survey Report. Report to the National Environmental Science Program, Marine Biodiversity Hub.

This dataset provides the locations and status, as at 30 June 2020, of Australian operating mines, mines under development, mines on care and maintenance and resource deposits associated with critical minerals. Developing mines are deposits where the project has a positive feasibility study, development has commenced or all approvals have been received. Mines under care and maintenance and resource deposits are based on known resource estimations and may produce critical minerals in the future.

These videos are recordings of online secondary teacher professional learning sessions, delivered by Geoscience Australia’s Education Team. “Can I Fall Down the Cracks?” Plate Tectonic Misconceptions Part 1 This session focused on common misconceptions that are encountered when teaching plate tectonics. The student misconceptions addressed are: 1. We can’t see the tectonic plates (starting at 5:35) 2. The mantle is made of liquid rock (starting at 11:25) 3. The plates move by convection in the mantle (starting at 17:35) 4. When plates collide one always goes under the other (starting at 22:15) 57 minutes total duration, with Q&A with an expert scientist starting at 34 minutes. “Can I Fall Down the Cracks?” Plate Tectonic Misconceptions Part 2 This session focused on common misconceptions that are encountered when teaching hazards associated with plate tectonics. The student misconceptions addressed are: 1. Earthquakes are measured using the Richter scale (starting at 3:15) 2. The magnitude of an earthquake depends on how far away it is (starting at 7:20) 3. Earthquakes can be predicted (starting at 10:52) This section includes a description of Raspberry Shake equipment: low cost earthquake monitoring for the classroom 4. There are no volcanoes in Australia (starting at 18:25) 5. You can surf a tsunami (starting at 24:17) 51 minutes total duration, with Q&A with an expert scientist starting at 37 minutes.

A dataset of potential geological sequestration sites has been compiled as part of the Australian Petroleum Cooperative Research Centre's GEODISC program. Sites have been identified across all Australian sedimentary basins.