3D structural and geological models that provide insight and understanding of the continents subsurface. The models capture 3D stratigraphy and architecture, including the depth to bedrock and the locations of different major rock units, faults and geological structures. <b>Value: </b>These models are valuable for exploration and reconstructions of Australia's evolution <b>Scope: </b>Contains a variety of 3D volumetric models and surfaces that were produced for specific projects at regional to continental scale.

The Topographic Position Index measures the topographic slope position of landforms by comparing the mean elevation of a specific neighbourhood area with the elevation value of a central cell. This is done for every cell or pixel in the digital elevation model (DEM) to derive the relative topographic position (e.g. upper, middle and lower landscape elements). Ruggedness informs on the roughness of the surface and is calculated as the standard deviation of elevations. Both these terrain components are used to generate a multi-scale topographic index over the Australian continent using the algorithm developed by Lindsay, J, B., Cockburn, J. M. H. and Russell, H. A. J., 2015. An integral image approach to performing multi-scale topographic position analysis, Geomorphology, 245, 51-61. Topographic position is captured across three spatial scale and display as a ternary image. The ternary image reveals a rich representation of nested landform features with broad application to geomorphological and hydrological process understanding and mapping of regolith and soils. <b>Value: </b>Broad application in understanding geomorphological and hydrological processes and in mapping regolith and soils over the Australian continent. Can be used as inputs into geospatial modelling and machine learning <b>Scope: </b>The dataset is national. The algorithm can be run on any digital elevation gridded dataset.

This data collection are comprised of magnetic surveys acquired across Australia by Commonwealth, State and Northern Territory governments and the private sector with project management and quality control undertaken by Geoscience Australia. Magnetic surveying is a geophysical method for measuring the intensity (or strength) of the Earth's magnetic field, which includes the fields associated with the Earth's core and the magnetism of rocks in the Earth's crust. Measuring the magnetism of rocks, in particular, provides a means for the direct detection of several different types of mineral deposits and for geological mapping. The magnetism of rocks depends on the volume, orientation and distribution of their constituent magnetic minerals (namely magnetite, monoclinic pyrrhotite, maghaemite and ilmenite). The instrument used in magnetic surveys is a magnetometer, which can measure the intensity of the magnetic field in nanoteslas (nT). Magnetic surveys in this collection have been acquired using aircraft or ship-mounted magnetometers and are a non-invasive method for investigating subsurface geology.

This data collection is comprised of radiometric (gamma-ray spectrometric) surveys acquired across Australia by Commonwealth, State and Northern Territory governments and the private sector with project management and quality control undertaken by Geoscience Australia. The radiometric method measures naturally occurring radioactivity arising from gamma-rays. In particular, the method is able to identify the presence of the radioactive isotopes potassium (K), uranium (U) and thorium (Th). The measured radioactivity is then converted into concentrations of the radioelements K, U and Th in the ground. Radiometric surveys have a limited ability to see into the subsurface with the measured radioactivity originating from top few centimetres of the ground. These surveys are primarily used as a geological mapping tool as changes in rock and soil type are often accompanied by changes in the concentrations of the radioactive isotopes of K, U and Th. The method is also capable of directly detecting mineral deposits. For example, K alteration can be detected using the radiometric method and is often associated with hydrothermal ore deposits. Similarly, the method is also used for U and Th exploration, heat flow studies, and environmental mapping purposes such as characterising surface drainage features. The instrument used in radiometric surveys is a gamma-ray spectrometer. This instrument measures the number of radioactive emissions (measured in counts per second) and their energies (measured in electron volts (eV)). Radiometric data are simultaneously acquired with magnetic data during airborne surveys and are a non-invasive method for investigating near-surface geology and regolith.

Relatively little is known about what the seafloor of Australia's continental shelf looks like or has living on it. Geoscience Australia (GA), together with other partners, undertakes a range of marine surveys to improve our understanding and management of Australia's marine environments. One component of the research involves the collection of underwater imagery to directly observe and characterise coastal and deep sea habitats. In some regions these surveys build on existing baseline knowledge, but in many areas, particularly deep offshore locations, these surveys provide the first images of the seafloor. The imagery collection includes both still and video imagery collected using various systems, including towed platforms, remotely operated vehicles (ROVs) and autonomous underwater vehicles (AUVs). Post-survey reports and metadata files are included as part of the collection, which describe further details of the surveys and respective imagery collections. The seafloor imagery provides a wealth of information about the geological features, habitats and life forms occurring throughout Australia's marine jurisdiction. <b>Value: </b>Improve the understanding and management of Australia's marine environments. <b>Scope: </b>GA surveys from 2007 onwards in waters around Australia and Australia's Antarctic Territory.

This collection includes calibrated time-series data and other products from Geoscience Australia's geomagnetic observatory network in Australia and Antarctica. Data dates back to 1924. <b>Value: </b>These data are used in mathematical models of the geomagnetic field, in resource exploration and exploitation, to monitor space weather, and for scientific research. The resulting information can be used for compass-based navigation, magnetic direction finding, and to help protect communities by mitigating the potential hazards generated by magnetic storms. <b>Scope: </b>Continuous geomagnetic time series data, indices of magnetic activity and associated metadata, Data dates back to 1924.

Segmented time series data for earthquake events. Data are in raw digital counts and have associated instrument metadata for calibration to physical ground-motion measures. These data are used to inform a range of applications in seismic hazard assessment and for assessing the utility of current observatory practice for magnitude assessment. <b>Value: </b>Used in the selection and development of ground-motion models used for seismic hazard purposes. These data also enable the assessment and development of new earthquake magnitude formulae. <b>Scope: </b>Data has been collected on an ad hoc basis, some early digital data dates back to 1989 (i.e. Newcastle earthquake), and the dataset continues to grow as earthquakes of interest occur, or various temporary deployments are rolled out. Instrument metadata is not always known.

Descriptions of and measurements from field sites and samples from geological (including regolith) surveys. <b>Value: </b>Used to constrained surface geology, important in resource exploration and understanding physical environment. <b>Scope: </b>Mapping surveys mainly in Australia, but also in Antarctica, Oceania and south-east Asia.

This collection contains all national level bathymetry grids held by Geoscience Australia (GA) dating back to survey data obtained since 1993. <b>Value: </b>Bathymetry data is used for a wide range of marine applications including: navigation, environmental assessment, jurisdictional boundaries, resource exploration. <b>Scope: </b>Data holdings lying within the offshore area of Australia, including international waters. <b>To access the AusSeaBed Marine Data Portal</b> use the following link: <a href="https://portal.ga.gov.au/persona/marine#/">https://portal.ga.gov.au/persona/marine#/</a>

This is a physical collection of photographic materials created by staff of Geoscience Australia (GA) and its predecessor organisations in the course of their work between the early 1920s and the early 21st century. <b>Value: </b>Historic and scientific significance. Many sites visited are remote and have rarely been revisited. Some images are of people from First Nations, flora and fauna of Australia, its territories and other countries. <b>Scope: </b> Geographical scope is largely Australia, pre- and post-Independence Papua New Guinea, and the Australian Antarctic Territory, but other countries and territories are represented. Thematic scope varies considerably, covering a diverse range of operations of a geological survey, including land and marine surveys, field installations, rock and fossil specimens (in situ, laboratory and under microscope), buildings, passport photographs, etc. The majority of the physical image collection (photos, negatives and glass plates) is still hardcopy only and stored in an access restricted room. This collection requires extensive work to develop a comprehensive catalogue of its contents and explore options for digitisation. <b>Queries can be directed to Records Management Unit (RMU) via the <a href="https://supportworkplace.ga.gov.au/CherwellPortal/Geoscience/">Support Workplace tool</a>. </b> More recent mages received from business area's and departing staff members have been digitised and are stored in HPRM folders: P14/50 - GA Image Collection (A20/615, A20/614, A20/598, A18/111) A spreadsheet containing metadata (D2019-4576) for these images (previously delivered via a now decommissioned database), can be viewed via the Download tab. Note: This HVC record is currently only visible to internal GA staff. <b>If anyone has any additional photographic collections that reflect the history of Geoscience Australia (or its predecessor organisations) the Records Management Unit would be very interested in chatting to you.</b>