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.

A large multibeam echo sounder (MBES) dataset (710, 000 km2, inclusive of transit data) was acquired in the SE Indian Ocean to assist the search for Malaysia Airlines Flight 370 (MH370). Here, we present the results of a geomorphic analysis of this new data and compare with the Global Seafloor Geomorphic Features Map (GSFM) that is based on coarser resolution satellite-derived bathymetry data. The analyses show that abyssal plains and basins are significantly more rugged than their representation in the GSFM, with a 20% increase in the extent of hills and mountains. The new model also reveals four times more seamounts than presented in the GSFM, suggesting a greater number of these features than previously estimated for the broader region and indeed globally. This is important considering the potential ecological significance of these high-relief structures. Analyses of the new data also enabled knolls, fans, valleys, canyons, troughs and holes to be identified, doubling the number of discrete features mapped and revealing the true geodiversity of the deep ocean in this area. This high-resolution mapping of the seafloor also provides new insights into the geological evolution of the region, both in terms of structural, tectonic, and sedimentary processes. For example, sub-parallel ridges extend over approximately 20% of the area mapped and their form and alignment provide valuable insight into Southeast Indian Ridge seafloor spreading processes. Rifting is recorded along the Broken Ridge – Diamantina Escarpment, with rift blocks and well-bedded sedimentary bedrock exposures discernible down to 2,400 m water depth. Ocean floor sedimentary processes are represented in sediment mass transport features, especially along and north of Broken Ridge, and pockmarks (the finest-scale features mapped) south of Diamantina Trench. The new MBES data highlight the complexity of the search area and serve to demonstrate how little we know about the 85-90% of the ocean floor that has not been mapped with this technology. The availability of high-resolution and accurate maps of the ocean floor can clearly provide new insights into the Earth’s geological evolution, modern ocean floor processes, and the location of sites that are likely to have relatively high biodiversity. Abstract presented the 2017 American Geophysical Union, Fall Meeting

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.

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 repository contains a static version of the data and software that accompanies the article by Stephenson et al. (2024) published in the Journal of Geophysical Research: Solid Earth. Note that the data and software repositories are up to date as of 07/03/2024. For more recent updates users are referred to the primary repositories on Github. Contents of zipped repository files includes four directories: 1. The manuscript directory `STEPHENSON_ET_AL_2024_JGR/` containing - The manuscript file (pre-print before final peer review and acceptance by the journal). - Supplementary text accompanying the manuscript. 2. The `SMV2rho` software package version `v1.0.1` for converting seismic velocity into density. 3. The `SeisCruST` database of global crustal thickness and velocity profiles. 4. The `global-residual-topography` database containing estimates of continental residual topography after correcting for isostatic effects of crustal thickness and density variations. Abstract for the article: Continental topography is dominantly controlled by a combination of crustal thickness and density variations. Nevertheless, it is clear that some additional topographic component is supported by the buoyancy structure of the underlying lithospheric and convecting mantle. Isolating these secondary sources is not straightforward, but provides valuable information about mantle dynamics. Here, we estimate and correct for the component of topographic elevation that is crustally supported to obtain residual topographic anomalies for the major continents, excluding Antarctica. Crustal thickness variations are identified by assembling a global inventory of 26 725 continental crustal thickness estimates from local seismological datasets (e.g. wide-angle/refraction surveys, calibrated reflection profiles, receiver functions). In order to convert crustal seismic velocity into density, we develop a parametrization that is based upon a database of 1 136 laboratory measurements of seismic velocity as a function of density and pressure. In this way, 4 120 new measurements of continental residual topography are obtained. Observed residual topography mostly varies between±1–2 km on wavelengths of 1 000–5 000 km. Our results are generally consistent with the pattern of residual depth anomalies observed throughout the oceanic realm, with long-wavelength free-air gravity anomalies, and with the distribution of upper mantle seismic velocity anomalies. They are also corroborated by spot measurements of emergent marine strata and by the global distribution of intraplate magmatism that is younger than 10 Ma. We infer that a significant component of residual topography is generated and maintained by a combination of lithospheric thickness variation and sub-plate mantle convection. Lithospheric composition could play an important secondary role, especially within cratonic regions.

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

The Officer-Musgrave project investigates the groundwater and energy resource potential of the Officer Basin and neighbouring Musgrave Province near the junction of South Australia, Western Australia and the Northern Territory (Figure 1). Groundwater investigations focus on the Musgrave Province and overlying Officer Basin to identify potential palaeovalley groundwater resources, to support geological framework data acquisition and geochemistry. Groundwater systems in remote regions, such as the Officer-Musgrave region, are poorly understood due to sparse geoscientific data and few detailed scientific inestigations having been undertaken. Characterising the distribution and quality of groundwater resources, will lead to a better understanding of the groundwater resources for community supply and economic development opportunities. The energy resource component of the project focuses on the analysis of existing legacy datasets, including seismic and well data, in the Officer Basin and acquisition of key new precompetitive data. These activities will improve understanding of regional resource potential, with the aim of stimulating industry exploration investment in the medium-term, ultimately leading to new discoveries and wealth creation. This work builds directly on work completed in the first phase of the Exploring for the Future program, which enhanced our understanding of Centralian Superbasin stratigraphy (Khider et al., 2021; Bradshaw et al., 2021). Presented to the 2022 Central Australian Basins Symposium IV (CABS) 29-30 August (https://agentur.eventsair.com/cabsiv/)

All modern ground motion prediction equations (GMPEs) are now calibrated to the moment magnitude scale MW, it is therefore essential that earthquake rates are also expressed in terms of moment magnitudes for probabilistic seismic hazard analyses. However, MW is not routinely estimated for earthquakes in Australia because of Australia’s low-to-moderate level of seismicity, coupled with the relatively sparse seismic recording networks. As a result, the Australian seismic catalogue has magnitude measures mainly based on local magnitudes, ML. To homogenise the earthquake catalogue based on a uniform MW, a “reference catalogue” that includes earthquakes with available MW estimates was compiled. This catalogue consists of 240 earthquakes with original MW values between 2.0 and 6.58. The reference catalogue served as the basis for the development of magnitude conversion equations between MW and ML. The conversions are developed using general orthogonal regression. Different functional forms for the conversion equations were considered and their impact on seismic hazard is explored. Synthetic earthquake catalogues with a “known” ­b-value are generated about an arbitrary location. These catalogues are subsequently perturbed according to different magnitude adjustment assumptions. It is found that the results of seismic hazard analyses at our site are sensitive to the implementation algorithm of such equations. For the considered scenario, the results show a 20-40% reduction in PGA hazard (at the 10% in 50-year probability of exceedance level), depending on the selection of the functional form as well as the method for applying the magnitude conversion equations. Presented at the 2018 Seismological Society of America (SSA) Annual Meeting

Publicly available geology data are compiled to provide a common information base for resource development and regulatory decisions in the north Bowen Basin region. This web service summarises the geology of the north Bowen Basin.

We consider how our society can use data, information and knowledge of the Earth under a broad definition of geoscience to better connect with the Earth system. This is important in our changing world, in particular how geoscience contributes to our response to the societal impacts of the COVID-19 pandemic. Ultimately, informed decisions utilizing the best geoscience data and information provide key parts of our economic, environmental and cultural recovery from the pandemic. The connection to country and more widely connection to our planet and the greater Earth system that comes from personal experience has been especially challenged in 2020. Much of Australia’s population have been encouraged to stay in our homes, first because of major fires and more recently in response to isolation from the COVID-19 pandemic. Although domestic travel became increasingly allowable, international travel has been restricted for much longer. This has increased the importance of trusted data and information initially from domestic locations and for more extended time between countries that are now less accessible. We discuss ways that geoscience governs our discovery and use of minerals, energy and groundwater resources and builds resilience and adaptation to environmental and cultural change. A broad definition of geoscience also includes positioning and location data and information, such as through integrated digital mapping, satellite data and real-time precise positioning. Important here is sharing, with two-way exchange of data, information and knowledge about the Earth, through outreach in geoscience education programs and interactions with communities across Australia, into neighboring countries in Asia and the Pacific, and across the world. An aspiration is for geoscience to inform social license through evidence-based decisions, such as for land and marine access, for a strong economy, resilient society and sustainable environment. At Geoscience Australia, we have developed a ten years strategic plan (Strategy 2028) that guides us to be a trusted source of information on Australia’s geology and geography for government, industry and community decision making. This will contribute to a safer, more prosperous and well-informed Australia and its connection to neighbouring countries, such as in Asia, as well as people that are better connected to country and our planet. <b>Citation:</b> Hill, S., Thorne, J., Przeslawski, R., Mouthaan, R., Lewis, C. The 'new normal' for geoscience in a post-COVID world: connecting informed people with the Earth. <i>Thai Geoscience Journal</i> Volume 2 (2) 2021, p30-37 021 ISSN-2730-2695; DOI-10.14456/tgj.2021.3