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  • In May 2013, Geoscience Australia (GA) and the Australian Institute of Marine Science (AIMS) undertook a collaborative seabed mapping survey (GA0340/ SOL5754) on the Leveque Shelf, a distinct geological province within the Browse Basin, offshore Western Australia. The purpose of the survey was to acquire geophysical and biophysical data on seabed environments over a previously identified potential CO2 injection site to better understand the overlying seabed habitats and to assess potential for fluid migration to the seabed. Mapping and sampling was undertaken across six areas using multibeam and single beam echosounders, sub-bottom profilers, sidescan sonar, underwater towed-video, gas sensors, water column profiler, grab samplers, and vibrocorer. Over 1070 km2 of seabed and water column was mapped using the multibeam and single beam echosounder, in water depths ranging between 40 and 120 m. The sub-surface was investigated using the multichannel and the parametric sub-bottom profilers along lines totalling 730 km and 1547 km in length respectively. Specific seabed features were investigated over 44 line km using the sidescan sonar and physically and sampled at 58 stations. Integration of this newly acquired data with existing seismic data will provide new insights into the geology of the Leveque Shelf. This work will contribute to the Australian Government's National CO2 Infrastructure Plan (NCIP) by providing key seabed environmental and geological data to better inform the assessment of the CO2 storage potential in this area of the Browse Basin. This dataset contains identifications of Polychaetes collected from 64 Smith-McIntyre grabs deployed during GA0340/SOL5754.

  • Australia has one of the world’s largest marine estates and has recently established the largest network of marine protected areas in the world. As such, Australia is now uniquely placed to develop standardised national approaches to monitor the marine environment. We have therefore developed a suite of field manuals for the acquisition of marine data from a variety of frequently-used sampling platforms so that data is directly comparable in time and through space. This will then facilitate a national monitoring program in Australian waters, with a particular focus on Australian Marine Parks (AMPs). Due to the large geographic area, diverse flora and fauna, and range of environmental conditions represented by the Australian marine estate, a single method of sampling is neither practical nor desirable. For this reason, we present a standard operating procedure (SOP) for each of six key marine benthic (i.e. seafloor) sampling platforms that were identified based on their frequency of use in previous sampling and monitoring programs: • Multibeam sonar (MBES) provides bathymetry and backscatter data that are used to map the seafloor. • Autonomous Underwater Vehicles (AUVs) acquire high-resolution continuous imagery of the seafloor and its associated habitats and organisms. • Benthic Baited Remote Underwater Video (BRUV) systems acquire video of demersal fish attracted to a baited camera system dropped to the seafloor. • Pelagic BRUVs acquire video of pelagic fish and other fauna that are attracted to a baited camera system suspended in the water column. This platform is included as an emergent sampling method for pelagic ecosystems. • Towed cameras acquire video or still imagery of the seafloor and its associated habitats and organisms. • Grabs and box corers collect sediment samples that can be analysed for biological, geochemical, or sedimentological variables. • Sleds and trawls collect benthic or demersal fauna near the seafloor. The main challenge in the development of these manuals was to find a balance between being overly prescriptive (such that everyone follows their existing protocols and ignores the manuals) and overly flexible (such that data is not consistent and therefore not comparable). A collaborative approach was paramount to addressing this concern. Ultimately, over 60 individuals from 28 organisations contributed to the field manual package. By engaging researchers, managers, and technicians from multiple agencies with a variety of experience, sea time, and subject matter expertise, we strove to ensure the field manuals represented the broader marine science community of Australia. This not only improved the content but also increased the potential for adoption across multiple agencies and monitoring programs. Future work is based on the understanding that SOPs should be periodically checked and revised, lest they become superseded or obsolete. Resources are available to develop a Version 2 of this field manual package, due for completion in late 2018. As part of this version, a long-term plan for managing the field manuals will be developed, including maintenance and version control.

  • 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. <b>To view catalogue records associated with this collection click on the keyword "HVC_144640" below</b>

  • <p>A new finite volume algorithm to solve the two dimensional shallow water equations on an unstructured triangular mesh has been implemented in the open source ANUGA software, which is jointly developed by the Australian National University and Geoscience Australia. The algorithm supports discontinuous-elevation, or 'jumps' in the bed profile between neighbouring cells. This has a number of benefits compared with previously implemented continuous-elevation approaches. Firstly it can preserve stationary states at wet-dry fronts without using any mesh porosity type treatment. It can also simulate very shallow frictionally dominated flow down sloping topography, as typically occurs in direct-rainfall flood models. In the latter situation, mesh porosity type treatments lead to artificial storage of mass in cells and associated mass conservation issues, whereas continuous elevation approaches with good performance on shallow frictionally dominated flows tend to have difficulties preserving stationary states near wet-dry fronts. The discontinuous elevation approach shows good performance in both situations, and mass is conserved to a very high degree, consistent with floating point error. <p>A further benefit of the discontinuous-elevation approach, when combined with an unstructured mesh, is that the model can sharply resolve rapid changes in the topography associated with e.g. narrow prismatic drainage channels, or buildings, without the computational expense of a very fine mesh. The boundaries between such features can be embedded in the mesh using breaklines, and the user can optionally specify that different elevation datasets are used to set the elevation within different parts of the mesh (e.g. often it is convenient to use a raster DEM in terrestrial areas, and surveyed channel bed points in rivers). <p>The discontinuous elevation approach also supports a simple and computationally efficient treatment of river walls. These are arbitrarily narrow walls between cells, higher than the topography on either side, where the flow is controlled by a weir equation and optionally transitions back to the shallow water solution for sufficiently submerged flows. This allows modelling of levees or lateral weirs much finer than the mesh size. <p>A number of benchmark tests are presented illustrating these features of the algorithm, along with its application to urban flood hazard simulation and comparison with field data. All these features of the model can be run in serial or parallel, on clusters or shared memory machines, with good efficiency on 10s - 100s of cores depending on the number of mesh triangles and other case-specific details.

  • Phase two of the China Australia Geological Storage of CO2 (CAGS2) project aimed to build on the success of the previous CAGS project and promote capacity building, training opportunities and share expertise on the geological storage of CO2. The project was led by Geoscience Australia (GA) and China's Ministry of Science and Technology (MOST) through the Administrative Centre for China's Agenda 21 (ACCA21). CAGS2 has successfully completed all planned activities including three workshops, two carbon capture and storage (CCS) training schools, five research projects focusing on different aspects of the geological storage of CO2, and ten researcher exchanges to China and Australia. The project received favourable feedback from project partners and participants in CAGS activities and there is a strong desire from the Chinese government and Chinese researchers to continue the collaboration. The project can be considered a highly successful demonstration of bi-lateral cooperation between the Australian and Chinese governments. Through the technical workshops, training schools, exchange programs, and research projects, CAGS2 has facilitated and supported on-going collaboration between many research institutions and industry in Australia and China. More than 150 experts, young researchers and college students, from over 30 organisations, participated in CAGS2. The opportunity to interact with Australian and international experts at CAGS hosted workshops and schools was appreciated by the participants, many of whom do not get the opportunity to attend international conferences. Feedback from a CAGS impact survey found that the workshops and schools inspired many researchers and students to pursue geological storage research. The scientific exchanges proved effective and often fostered further engagement between Chinese and Australian researchers and their host organisations. The research projects often acted as a catalyst for attracting additional CCS funding (at least A$700,000), including two projects funded under the China Clean Development Mechanism Fund. CAGS sponsored research led to reports, international conference presentations, and Chinese and international journal papers. CAGS has established a network of key CCS/CCUS (carbon capture, utilisation and storage) researchers in China and Australia. This is exemplified by the fact that 4 of the 6 experts that provided input on the 'storage section of the 12th Five-Year plan for Scientific and Technological Development of Carbon Capture, Utilization and Storage, which laid out the technical policy priorities for R&D and demonstration of CCUS technology in China, were CAGS affiliated researchers. The contributions of CAGS to China's capacity building and policy CCUS has been acknowledged by the Chinese Government. CAGS support of young Chinese researchers is particularly noted and well regarded. Letters have been sent to the Secretary of the Department of Industry and Science and to the Deputy CEO of Geoscience Australia, expressing China's gratitude for the Australian Government's support and GA's cooperation in the CAGS project.

  • This report provides the first comprehensive assessment of geomorphological and geological features of the Great Barrier Reef (GBR) whose intrinsic characteristics represent elements of the Outstanding Universal Value (OUV) of the Great Barrier Reef World Heritage Area (GBRWHA). Specific examples of these features are described and an initial assessment made of the environmental pressures that they currently or in the future may experience. Importantly, the information compiled in this report improves our knowledge of an important set of physical and biophysical features in the GBRWHA with key natural heritage values and thereby has the potential to better inform the conservation and management of this unique region.

  • This dataset contains seascape classification layer derived from bathymetry and backscatter, and their derivative from seabed mapping surveys in Darwin Harbour. The survey was undertaken during the period 24 June to 20 August 2011 by iXSurvey Australia Pty Ltd for the Department of Natural Resources, Environment, The Arts and Sport (NRETAS) in collaboration with Geoscience Australia (GA), the Darwin Port Corporation (DPC) and the Australian Institute of Marine Science (AIMS) using GA's Kongsberg EM3002D multibeam sonar system and DPC's vessel Matthew Flinders. The survey obtained detailed bathymetric map of Darwin Harbour. Refer to the GA record ' Mapping and Classification of Darwin Harbour Seabed' for further information on processing techniques applied (GeoCat: 79212; GA Record: 2015/xx)

  • This dataset provides the spatially continuous data of seabed gravel (sediment fraction >2000 µm), mud (sediment fraction < 63 µm) and sand content (sediment fraction 63-2000 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.0025 decimal degree (dd) resolution raster grids format and ascii text file. The dataset covers the Browse region in the Australian continental EEZ. This dataset supersedes previous predictions of sediment gravel, mud and sand content for the basin with demonstrated improvements in accuracy. Accuracy of predictions varies based on density of underlying data and level of seabed complexity. Artefacts occur in this dataset as a result of insufficient samples in relevant regions. This dataset is intended for use at the basin scale. The dataset may not be appropriate for use at smaller scales in areas where sample density is insufficient to detect local variation in sediment properties. To obtain the most accurate interpretation of sediment distribution in these areas, it is recommended that additional samples be collected and predictions updated.

  • This resource contains sediment data for the Oceanic Shoals Commonwealth Marine Reserve (CMR) in the Timor Sea collected by Geoscience Australia during September and October 2012 on RV Solander (survey GA0339/SOL5650). Seabed sediment samples were collected from four survey areas by either a Smith McIntyre grab or box corer at 62 stations, divided between Area 1 (n=22), Area 2 (n=17), Area 3 (n=21) and Area 4 (n=2). The Oceanic Shoals Commonwealth Marine Reserve survey was undertaken as an activity within the Australian Government's National Environmental Research Program Marine Biodiversity Hub and was the key component of Research Theme 4 - Regional Biodiversity Discovery to Support Marine Bioregional Plans. Hub partners involved in the survey included the Australian Institute of Marine Science, Geoscience Australia, the University of Western Australia, Museum Victoria and the Museum and Art Gallery of the Northern Territory. Data acquired during the survey included: multibeam sonar bathymetry and acoustic backscatter; sub-bottom acoustic profiles; physical samples of seabed sediments, infauna and epibenthic biota; towed underwater video and still camera observations of seabed habitats; baited video observations of demersal and pelagic fish, and; oceanographic measurements of the water column from CTD (conductivity, temperature, depth) casts and from deployment of sea surface drifters. Further information on the survey is available in the post-survey report published as Geoscience Australia Record 2013/38 (Nichol et al. 2013).

  • This dataset contains probability values of rocky/hard seabed (multibeam angular backscatter response derived product) from seabed mapping surveys in Darwin Harbour. The survey was undertaken during the period 24 June to 20 August 2011 by iXSurvey Australia Pty Ltd for the Department of Natural Resources, Environment, The Arts and Sport (NRETAS) in collaboration with Geoscience Australia (GA), the Darwin Port Corporation (DPC) and the Australian Institute of Marine Science (AIMS) using GA's Kongsberg EM3002D multibeam sonar system and DPC's vessel Matthew Flinders. The survey obtained detailed bathymetric map of Darwin Harbour. Refer to the GA record ' Mapping and Classification of Darwin Harbour Seabed' for further information on processing techniques applied (GeoCat: 79212; GA Record: 2015/xx)