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 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.

<div>The People and Culture Strategy 2028 articulates Geoscience Australia’s aspirations for who we are, and how we work<strong>. </strong>Through strategic people and culture principles, this Strategy outlines Geoscience Australia's plan to recruit, develop and retain the workforce necessary to advance Earth sciences in Australia. These strategic principles are interdisciplinary excellence, strengthened safety performance, success through diversity, leaders at all levels and collaborating for impact.&nbsp;</div><div><br></div>

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

Satellite navigation is an important capability in our modern lives—we use it to find the nearest petrol station, order food at home, and track an arriving package. Accurate satellite-enabled positioning and timing technology is also becoming vital in many industrial sectors of the economy, including transport, agriculture, resources, and utilities. On behalf of the Australian government and in partnership with New Zealand, Geoscience Australia is improving satellite navigation capability for everyone with the Southern Positioning Augmentation Network, or SouthPAN. SouthPAN is a Satellite-Based Augmentation System that will use new spacecraft, ground sensors, and other infrastructure to broadcast corrections that complement existing Global Navigation Satellite Systems—like GPS, for example. SouthPAN services will commence in 2022 and be progressively improved in the coming years, ultimately being used in their most critical application: by aircraft to land at airports.

Since the publication of the Global Seismic Hazard Assessment Project (GSHAP) hazard map in 1999, Australia has stood out as a region of high earthquake hazard among its stable continental region (SCR) peers. The hazard map underpinning the GSHAP traces its lineage back to the 1990 assessment of Gaull and others. This map was modified through a process of expert judgement in response to significant Australian earthquakes (notably the MW 6.2, 6.3 and 6.6 1988 Tennant Creek sequence and the deadly 1989 MW 5.4 Newcastle earthquake). The modified map, developed in 1991 (McCue and others, 1993), underpins Standards Australia’s structural design actions to this day (AS1170.4–2007). But does this assessment make sense with our current understanding of earthquake processes in SCRs? Geoscience Australia (GA) have embarked to update the seismic hazard model for Australia through the National Seismic Hazard Assessment (NSHA18) project. Members of the Australian seismological community were solicited to contribute alternative seismic source models for consideration as inputs to the updated Australian NSHA18. This process not only allowed for the consideration of epistemic uncertainty in the hazard model in a more comprehensive and transparent manner, but also provides the community as a whole ownership of the final model. The 3rd party source models were assessed through an expert elicitation process that weighed the opinion of each expert based on their knowledge and ability to judge relevant uncertainties. In total, 19 independent seismic source models (including regional and background area sources, smoothed seismicity and seismotectonic sources) were considered in the complete source model. To ensure a scientifically rigorous, transparent and quality product, GA also established a Scientific Advisory Panel to provide valuable and ongoing feedback during the development of the NSHA18. The NSHA18 update yields many important advances on its predecessors, including: calculation in a full probabilistic framework using the OpenQuake-engine; consistent expression of earthquake magnitudes in terms of MW; inclusion of epistemic uncertainty through the use of third-party source models; inclusion of a national fault-source model based on the Australian Neotectonic Features database; inclusion of epistemic uncertainty on fault occurrence models and earthquake clustering; and the use of modern ground-motion models. The preliminary NSHA18 design values are significantly lower than those in the current (1991-era) AS1170.4–2007 map at the 10% in 50-year probability level. However, draft values at lower probabilities (i.e., 2% in 50-years) are entirely consistent (in terms of the percentage land mass exceeding different PGA thresholds) with other SCRs with low strain rates (e.g. the central & eastern United States). The large reduction in seismic hazard at the 10% in 50-year probability level has led to much consternation amongst the building code committee in terms of whether the new draft design values will allow enough resilience to seismic loads. This process underscores the challenges in developing national-scale PSHAs in slowly deforming regions, where 10% in 50-year probability level may not adequately capture the maximum considered earthquake ground motions. Consequently, a robust discussion is required is amongst the Australian building code committee (including hazard practitioners) to determine alternative hazard and/or risk objectives that could be considered for future standards. Presented at the Probabilistic Seismic Hazard Assessment (PSHA) Workshop 2017, Lenzburg, Switzerland

There are a number of global initiatives to understand and mitigate the impacts of extreme space weather on critical infrastructure and modern society. This paper provides the results of an analysis to estimate extreme geoelectric field values for the Australian region to facilitate evaluation of Australia's power system response to extreme geomagnetic storms. Geoelectric fields are calculated using a grid of modeled magnetotelluric impedance tensors obtained from a 3‐D conductivity model of the Australian region. Statistical metrics derived from grids of geoelectric field time series are analyzed as a function of Dst index for different storm days to extrapolate geoelectric fields to extreme storm levels over a range of ground conductivity conditions. For Carrington event storm levels, geoelectric field values of 5.3 ± 3.8 V/km in the north‐south direction and 9.6 ± 4.3 V/km in the east-west direction are expected for areas of electrically resistive rocks near coastlines that are adjacent to deep highly conductive oceans, and inland, where there are large contrasts between the electrical conductivities of different rock types across Australia. Further, geoelectric field values may change by at least an order of magnitude over the grid spacing interval of 50 km in these areas. The results of the analysis also suggest that upscaling grids of geoelectric field time series derived from an observed storm by the ratio of extreme storm Dst to the observed storm Dst are a valid approach for the Australian region that provides extreme storm scenarios for different storm morphologies. <b>Citation:</b> Marshall, R., Dziura, L., Wang, L., Young, J., & Terkildsen, M. (2020). Estimating extreme geoelectric field values for the Australian region. <i>Space Weather</i>, 18, e2020SW002512. https://doi.org/10.1029/2020SW002512

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

Geoscience Australia (GA) has embarked on a project to update the seismic hazard model for Australia through the National Seismic Hazard Assessment (NSHA18) project. The draft NSHA18 update yields many important advances on its predecessors, including: 1) calculation in a full probabilistic framework using the Global Earthquake Model’s OpenQuake-engine; 2) consistent expression of earthquake magni-tudes in terms of moment magnitude, MW; 3) inclusion of epistemic uncertainty through the use of alterna-tive source models; 4) inclusion of a national fault-source model based on the Australian Neotectonic Features database; 5) the use of modern ground-motion models; and 6) inclusion of epistemic uncertainty on seismic source models, ground-motion models and fault occurrence and earthquake clustering models. The draft NSHA18 seismic design ground motions are significantly lower than those in the current (1991-era) AS1170.4–2007 hazard map at the 1/500-year annual ground-motion exceedance probability (AEP) level. However, draft values at lower probabilities (i.e., 1/2475-year AEP) are entirely consistent, in terms of the percentage area of land mass exceeding different ground-motion thresholds, with other Stable Continental Regions (e.g., central & eastern United States). The large reduction in seismic hazard at the 1/500-year AEP level has led to engineering design professionals questioning whether the new draft design values will provide enough structural resilience to potential seismic loads from rare large earthquakes. This process underscores the challenges in developing national-scale probabilistic seismic hazard analyses (PSHAs) in slowly-deforming regions, where a 1/500-year AEP design level is likely to be much lower than the ANCOLD Maximum Credible Earthquake (MCE) ground motions. Consequently, a robust discussion among the Standards Australia code committee, hazard practitioners and end users is required to consider alternative hazard and/or risk objectives for future standards. Site-specific PSHAs undertaken for owners and operators of extreme and high consequence dams generally require hazard evaluations at lower probabilities than for typical structural design as recommended in AS1170.4. However, modern national assessments, such as the NSHA18, can provide a benchmark in terms of recommended seismicity models, fault-source models, ground-motion models, as well as hazard values, for low-probability site-specific analyses. With a new understanding of earthquake processes in Australia leading to lower ground-motion hazard values for higher probability events (e.g., 1/500-year AEP), we should also ask whether the currently recommended design probabilities provide an acceptable level of seismic resilience to critical facilities (such as dams) and regular structures. Abstract presented at the 2017 Australian National Committee on Large Dams (ANCOLD) Conference