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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.

  • A rich trove of marine geophysical data acquired in the search for missing flight MH370 is yielding knowledge of ocean floor processes at a level of detail rare in the deep ocean. The tragic disappearance of Malaysian Airlines flight MH370 on 8 March 2014 has led to a deep ocean search effort of unprecedented scale and detail. Between June 2014 and June 2016, state-of-the-art shipboard multibeam echosounder (MBES) and sub-bottom profile data were collected in a ~255,000 km2 zone of the southeastern Indian Ocean. The arcuate, NE-SW oriented search swath (75 to 160 km wide) centers on Broken Ridge and extends ~2500 km from the eastern flank of Batavia Seamount to the Geelvinck Fracture Zone (Figure 1). Aircraft debris found along the shores of the western Indian Ocean is consistent with drift modelling that indicates an origin in the search area (https://www.atsb.gov.au/mh370/). The resultant dataset constitutes the largest MBES mapping effort for the Indian Ocean, representing about half the size of California, improving spatial resolution of the ocean floor in this region from an average of >5 km2 to <0.1 km2. Importantly, the new data provide the geospatial framework for the current phase of the search – deployment of deep-water, high-resolution acoustic and optical imaging instruments able to identify aircraft wreckage. <b>Citation:</b> Picard, K.,Brooke, B., and Coffin, M. F. (2017), Geological insights from Malaysia Airlines flight MH370 search, <i>Eos</i>, 98, https://doi.org/10.1029/2017EO069015. Published on 06 March 2017.

  • A high-resolution multibeam echosounder (MBES) dataset covering over 279,000 km2 was acquired in the southeastern Indian Ocean to assist the search for Malaysia Airlines Flight 370 (MH370) that disappeared on 8 March 2014. The data provided an essential geospatial framework for the search and is the first large-scale coverage of MBES data in this region. Here we report on geomorphic analyses of the new MBES data, including a comparison with the Global Seafloor Geomorphic Features Map (GSFM) that is based on coarser resolution satellite altimetry data, and the insights the new data provide into geological processes that have formed and are currently shaping this remote deepsea area. Our comparison between the new MBES bathymetric model and the latest global topographic/bathymetric model (SRTM15_plus) reveals that 62% of the satellite-derived data points for the study area are comparable with MBES measurements within the estimated vertical uncertainty of the SRTM15_plus model (± 100 m). However, > 38% of the SRTM15_plus depth estimates disagree with the MBES data by > 100 m, in places by up to 1900 m. The new MBES data show that abyssal plains and basins in the study area 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 more of these features than previously estimated for the broader region. This is important considering the ecological significance of high-relief structures on the seabed, such as hosting high levels of biodiversity. Analyses of the new data also enabled sea knolls, fans, valleys, canyons, troughs, and holes to be identified, doubling the number of discrete features mapped. Importantly, mapping the study area using MBES data improves our understanding of the geological evolution of the region and reveals a range of modern sedimentary processes. For example, a large series of ridges extending over approximately 20% of the mapped area, in places capped by sea knolls, highlight the preserved seafloor spreading fabric and provide valuable insights into Southeast Indian Ridge seafloor spreading processes, especially volcanism. Rifting is also recorded along the Broken Ridge – Diamantina Escarpment, with rift blocks and well-bedded sedimentary bedrock outcrops discernible down to 2400 m water depth. Modern ocean floor sedimentary processes are documented by sediment mass transport features, especially along the northern margin of Broken Ridge, and in pockmarks (the finest-scale features mapped), which are numerous south of Diamantina Trench and appear to record gas and/or fluid discharge from underlying marine sediments. The new MBES data highlight the complexity of the search area and serve to demonstrate how little we know about the vast areas of the ocean that have not been mapped with MBES. 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. <b>Citation:</b> Kim Picard, Brendan P. Brooke, Peter T. Harris, Paulus J.W. Siwabessy, Millard F. Coffin, Maggie Tran, Michele Spinoccia, Jonathan Weales, Miles Macmillan-Lawler, Jonah Sullivan, Malaysia Airlines flight MH370 search data reveal geomorphology and seafloor processes in the remote southeast Indian Ocean, <i>Marine Geology</i>, Volume 395, 2018, Pages 301-319, ISSN 0025-3227, https://doi.org/10.1016/j.margeo.2017.10.014.

  • 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.

  • Geoscience Australia’s Exploring for the Future program provides precompetitive information to inform decision-making by government, community and industry on the sustainable development of Australia's mineral, energy and groundwater resources. By gathering, analysing and interpreting new and existing precompetitive geoscience data and knowledge, we are building a national picture of Australia’s geology and resource potential. This leads to a strong economy, resilient society and sustainable environment for the benefit of all Australians. This includes supporting Australia’s transition to net zero emissions, strong, sustainable resources and agriculture sectors, and economic opportunities and social benefits for Australia’s regional and remote communities. The Exploring for the Future program, which commenced in 2016, is an eight year, $225m investment by the Australian Government. The name ‘Birrindudu Basin’ was first introduced by Blake et al. (1975) and Sweet (1977) for a succession of clastic sedimentary rocks and carbonates, originally considered to be Paleoproterozoic to Neoproterozoic in age, and overlain by the Neoproterozoic Victoria Basin (Dunster et al., 2000), formerly known as the Victoria River Basin (see Sweet, 1977).

  • Geoscience Australia has permanently deployed 40 trihedral corner reflectors in Queensland, Australia, covering an area of approximately 20,000 km2. The array of corner reflectors was constructed as part of the AuScope Australian Geophysical Observing System (AGOS) initiative to monitor crustal deformation using Interferometric Synthetic Aperture Radar (InSAR) techniques. The array includes 34 corner reflectors of 1.5m, 3 reflectors of 2.0m and 3 reflectors of 2.5m inner leg dimensions. Through the design process and the precision manufacturing techniques employed, the corner reflectors are also highly suitable for calibration and validation of satellite-borne Synthetic Aperture Radar (SAR) instruments. Nine of the 1.5m corner reflectors in the AGOS array had their Radar Cross Section (RCS) individually characterised at the Defence Science and Technology Organisation¿s outdoor ground reflection range, prior to permanent deployment in Queensland. The RCS measurements for the corner reflectors were carried out at X and C-band frequencies for both horizontal and vertical transmit-receive polarisations, and at a range of elevation and azimuth alignments. The field performance of the AGOS corner reflectors has been studied using SAR data from a range of satellites including Sentinel-1A. This study focuses on the calibration of the Sentinel-1A satellite presenting results from exercises undertaken both at Geoscience Australia and the European Space Agency¿s Mission Performance Centre as part of the satellite commissioning and routine phases. Radiometric calibration results in conjunction with geometric calibration and validation results for Sentinel-1A products from Stripmap and Terrain Observation with Progressive Scans (TOPS) modes are presented in this paper. The current configuration for most corner reflectors in the AGOS array is set to serve calibration requirements for a broad range of SAR missions on ascending orbital passes. However, the design allows for mission-specific corner reflector alignment if needed, as in the case of the 2.5m and 2.0m reflectors which have specifically been aligned to support calibration of the L-band SAR instrument on ALOS-2. Results reported in this paper could inform the need for re-configuring one or more corner reflectors in the array to specifically support ongoing calibration of the Sentinel-1A and B satellites. The permanently deployed AGOS corner reflector infrastructure presents an opportunity for independent calibration and comparison of SAR instruments on current and future satellite missions, and is considered an important Australian contribution to the global satellite calibration and validation effort. Presented at the 2016 Living Planet Symposium (LPS16) Prague, Czech Republic

  • The rapid growth in global sensor networks is leading to an explosion in the volume, velocity and variety of geospatial and geoscientific data. This coupled with the increasing integration of geospatial data into our everyday lives is also driving an increasing expectation of spatial information on-demand, and with minimal delay. However, there remains a gap between these expectations and the present reality of accessible information products and tools that help us understand the Living Planet. A solution can only be achieved through the development and implementation of common analytical frameworks that enable large scale interoperability across multiple data infrastructures. Success has been achieved using discrete global grid systems (DGGS). A DGGS is a form of Earth reference system that represents the Earth using a tessellation of discrete nested cells and is designed to ensure a repeatable representation of measurements that is better suited to today's requirements and technologies rather than for primarily navigation and manual charting purposes. A DGGS presents a common framework that is capable of linking very large multi-resolution and multi-domain datasets together to enable the next generation of analytic processes to be applied. There are many possible DGGS, each with their own advantages and disadvantages; however, there exists a common set of key characteristics that enable the standardization of DGGS to be achieved. Through the Open Geospatial Consortium (OGC) a new standard has been developed to define these essential characteristics of DGGS infrastructures and the core functional algorithms necessary to support the operation of and interoperability between DGGS. This paper describes the key elements of the new OGC DGGS Core Standard and how DGGS relate to the Living Planet. Examples from a number of conformant DGGS implementations will be used to demonstrate the immense value that can be derived from the adoption of a DGGS approach to issues of serious concern for the planet we live on. Presented at the 2016 Living Planet Symposium (LPS16) Prague, Czech Republic

  • This OGC Web Map Service (WMS) contains geospatial seabed morphology and geomorphology information for Cairns Seamount within the Coral Sea Marine Park and are intended for use by marine park managers, regulators, the general public and other stakeholders. This web service uses the data product published in McNeil et al. (2023); eCat Record 147998.

  • This OGC Web Feature Service (WFS) contains geospatial seabed morphology and geomorphology information for Flinders Reefs within the Coral Sea Marine Park and are intended for use by marine park managers, regulators, the general public and other stakeholders. This web service uses the data product published in McNeil et al. (2023); eCat Record 147998.

  • This OGC Web Map Service (WMS) contains geospatial seabed morphology and geomorphology information for Flinders Reefs within the Coral Sea Marine Park and are intended for use by marine park managers, regulators, the general public and other stakeholders. This web service uses the data product published in McNeil et al. (2023); eCat Record 147998.