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  • 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.

  • <div>The Varzin Passage to Merkara Shoal&nbsp;bathymetry survey was acquired for the Australian Hydrographic Office (AHO) during the period 4 Sep 2023 – 12 Apr 2024. This was a contracted survey conducted for the Australian Hydrographic Office by Fugro Australia as part of the Hydroscheme Industry Partnership Program. The survey area encompasses an area in Varzin Passage to Merkara Shoal. Bathymetry data was acquired using a LADS HD+, and processed using CARIS HIPS and SIPS, and QIMERA processing software. The dataset was then exported as a 30m resolution, 32 bit floating point GeoTIFF grid of the survey area.</div><div>This dataset is not to be used for navigational purposes.</div>

  • 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 European Union¿s Copernicus programme will change the global Earth observation landscape, providing vast amounts of data on an operational basis over the long term. However, the huge data volumes that are the strength of Copernicus also present its major challenge. Ensuring that this volume of data is made available in forms that make it usable is very challenging. Old paradigms based on each individual user downloading all data to local systems for their own applications will not scale sufficiently to support the volumes of data that Copernicus will produce. Particular technical challenges exacerbate these issues in the region around Australia: South-East Asia and the Pacific. Bandwidth is often limited, and data storage for huge volumes of data can be problematic. Tackling these problems at the level of individual institutions or users, where data is downloaded many times, is even more problematic; and when implemented, such ¿silo¿ type solutions create barriers to collaboration across domains and disciplines that Copernicus, by virtue of the comprehensiveness and consistency of the data it offers, makes possible. Australia is using its location in the region, and its expertise, to support the European Union to address these challenges. Through the Regional Copernicus Data Access/Analysis Hub, Australia will greatly improve access to Copernicus data for users in the South-East Asia and Pacific region. This will include providing access to very large volumes of Copernicus data ready for use and analysis. This will help avoid key barriers, particularly those caused by limited bandwidth in some parts of the region, and those related to the challenges of storing the Petabytes of data that Copernicus will generate in multiple locations. As well as overcoming significant technical challenges that would otherwise prevent effective exploitation of Copernicus data within a specific country in the region, the Regional Copernicus Data Access/Analysis Hub is also intended to provide a platform to enhance collaboration across borders. By enabling users from across nations, and across disciplines and sectors, to work together ¿around¿ the same data, and share and combine their results, barriers to cooperation and collaboration are broken down. This, in turn, enables people to work together more effectively in pursuit of the goals of fora such as Asia-Pacific Economic Cooperation and Association of South East Asian Nations. Tackling challenges like sustainable livelihoods, growth of the blue economy, and climate change become easier. This paper reviews the history and status of the initiative, describes the unique approaches that are being taken to establish the data infrastructure, discusses how it will enable effective exploitation of Copernicus data across the South East Asia and Pacific region, and discusses how federal and state governments are collaborating to establish something that ¿gives back¿, in a very concrete way, to the nations that provide the satellite data that is so important to Australia. Presented at the 2016 Living Planet Symposium (LPS16) Prague, Czech Republic

  • Coastal environments are intrinsically dynamic and respond to a wide array of natural and anthropogenic drivers across a broad range of time steps. In addition, coastal environments are under increasing pressure from land use intensification and climate change. The development of the Australian Geoscience Data Cube has delivered an unprecedented capability to support environmental change monitoring applications through rapid processing and analysis of standardised Earth Observation (EO) time-series data in a High Performance Computing environment. Standardised long-term EO data records provide the capacity to monitor coastal changes processes and understand current changes from a historical perspective. The ability to visualise environmental changes in a spatio-temporal context provides the opportunity to assess whether the change phenomena are rapid / gradual onset, and/or episodic / cyclical in nature. Understanding the spatio-temporal nature of the changes also enables the attribution of observed changes to the potential causes. Hovmöller diagrams, typically used to plot meteorological data, can be applied for visualising large datasets in a meaningful way. In this study, we apply Hovmöller plots to examine coastal change processes and estuarine dynamics, based on a time-series of Landsat based surface reflectance data over a 27-year period (1987-2014), within the Australian Geoscience Data Cube. The Hovmöller plot in Figure 1 highlights the timing of a sea wall installation and associated land reclamation processes near Fremantle, Western Australia (see PDF attachment).Three coastal change processes are illustrated in this study: 1. The opening, closing and migration of the mouth of the Glenelg River in Victoria; the Hovmöller plots show that the river mouth moves on an episodic basis and remains closed for periods of time. 2. The installation of a sea wall and subsequent land reclamation near Fremantle in Western Australia; the results illustrate rapid anthropogenic change in the coastal zone and highlight the timing of the sea wall installation and land reclamation processes. 3. The migration of coastal dune fields north of Perth in Western Australia; the results show slow coastal change processes through the gradual northward migration of the dune field over multi-decadal time scales. The availability of standardised long-term Landsat data, in conjunction with new data becoming available from the Copernicus Sentinel-2 missions, point to the need for cross calibrated multi-sensor data, to enrich the global long-term EO record, in support of the detection and characterisation of coastal change phenomena. Presented at the 2016 Living Planet Symposium (LPS16) Prague, Czech Republic

  • Digital Earth Australia (DEA) is a world-class digital infrastructure that uses satellite data, in the form of images and information, to detect physical changes across Australia in unprecedented detail. It identifies soil and coastal erosion, crop growth, water quality and changes to cities and regions. DEA provides government, industry, and individuals with the high-quality data and tools required for policy and investment decision-making. DEA will support industry productivity and innovation and the development of new digital products and services. These capabilities will improve decision-making, increase business efficiency, bolster profits and create jobs. For more information visit www.ga.gov.au/dea

  • 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

  • A ground-motion dataset from moderate-to-large magnitude earthquakes is compiled for earthquakes occurring in Proterozoic and Archean terranes of the Australian continental crust. Data, which are predominantly weak-motion velocity recordings, are compiled from low-sample-rate continuous waveform buffers and segmented high-sample-rate data (where available) recorded by the Australian National Seismograph Network (ANSN). Additional data are retrieved from various temporary deployments and, more recently, from the Incorporated Research Institutions for Seismology (IRIS) data centre. All raw data were first converted to a uniform miniSEED format from various binary and ASCII formats used over time. Corresponding instrument metadata is compiled in the standard FDSN StationXML format. The dataset currently contains 1497 earthquake recordings from 164 earthquakes occurring between 1990 and 2019. The magnitudes of earthquakes within the dataset range from MW 2.5 to 6.1 with hypocentral distances up to 1500 km. The time-series data are consistently processed to correct for the instrument response and to reduce the effect of background noise. A range of engineering parameters are calculated in time and frequency domains using the USGS’s ground-motion processing software, “gmprocess”. Numerous near-source recordings exceed peak accelerations of 0.10 g and range up to 0.66 g, while the maximum peak velocity of the dataset exceeds 27 cm/s. In spite of the limited number of seismic stations located throughout the Australian continental landmass, the dataset compiled herein will improve characterisation of ground-motion attenuation in the region and will provide an excellent supplement to ground-motion datasets collected in analogue seismotectonic regions worldwide. Presented at the 2021 Seismological Society of America (SSA) Annual Meeting

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    The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This radiometric uranium grid has a cell size of degrees (approximately 40m) and shows uranium element concentration of the Yathong airborne magnetic gradient and radiometric survey, 2023 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2023 by the NSW Government, and consisted of 65504 line-kilometres of data at 200m line spacing and 80m terrain clearance.

  • 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