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  • In this study, we aim to identify the most accurate methods for spatial prediction of seabed gravel content in the northwest Australian Exclusive Economic Zone. We experimentally examined: 1) whether input secondary variables affect the performance of RFOK and RFIDW, 2) whether the performances of RF, SIMs and their hybrid methods are data-specific, and 3) whether model averaging improves predictive accuracy of these methods in the study region. For RF and the hybrid methods, up to 21 variables were used as predictors. The predictive accuracy was assessed in terms of relative mean absolute error and relative root mean squared error based on the average of 100 iterations of 10-fold cross validation. In this study, the following important findings were achieved: - the predictive errors fluctuate with the input secondary variables; - the existence of correlated variables can alter the results of model selection, leading to different models; - the set of initial input variables affects the model selected; - the most accurate model can be missed out during the model selection; - RF, RFOK and RFIDW prove to be the most accurate methods in this study, with RFOK preferred; and these methods are not data-specific, but their models are, so best model needs to be identified; and - Model averaging is clearly data-specific. In conclusion, model selection is essential for RF and the hybrid methods. RF and the hybrid methods are not data-specific, but their models are. RFOK is the most accurate method. Model averaging is also data-specific. Hence best model needs to be identified for individual studies and application of model averaging should also be examined accordingly. RF and the hybrid methods have displayed substantial potentials for predicting environmental properties and are recommended for further test for spatial predictions in environmental sciences and other relevant disciplines in the future. This study provides suggestions and guidelines for improving the spatial predictions of biophysical variables in both marine and terrestrial environments.

  • Data package containing an ESRI shapefile and associated comma-separated value table (.csv) of the Pacific islands, including the countries of Cook Islands, Federated States of Micronesia, Fiji, Kiribati, Nauru, Niue, Palau, Papua New Guinea, Republic of Marshall Islands, Samoa, Solomon Islands, Tokelau, Tonga, Tuvalu and Vanuatu. The ESRI shapefile contains polygons of the islands and has been adapted from the World Vector Shoreline dataset, with original scale suitability of 1:250,000 (reference: Soluri, E.A. and Woodson, V.A. 1990. World Vector Shoreline. International Hydrographic Review LXVII(1)). See lineage for more information. The .csv file contains tabular data associated with the island polygons. The file has been adapted to suit the purposes of the companion report by Dixon-Jain et al. (2014). The island polygon shapefile and .csv file can be joined using the common UniqueID field. The attribute fields within the .csv file include island hydrogeological and physical characteristics. Relative ratings for component of the potential vulnerability framework are included for the two projection periods (2035-2064 and 2070-2099), for each climate hazard (low rainfall periods and mean sea-level rise). See the field list within lineage in the Data Dictionary for more information on the source of each attribute. The full bibliographic reference for the companion report (catalogue number 79066) is: Dixon-Jain, P., Norman, R., Stewart, G., Fontaine, K., Walker, K., Sundaram, B., Flannery, E., Riddell, A., Wallace, L. 2014. Pacific Island Groundwater and Future Climates: First-Pass Regional Vulnerability Assessment. Record 2014/43. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2014.043

  • Presentation to be delivered at the Western Australian Marine Science Institution Symposium, Fremantle, 21 February Abstract text: Geoscience Australia, as the Australian Government's geoscience agency, has a long history of marine environment mapping and research on the North West Shelf of Australia. In recent times, several data acquisition surveys have been completed and subsequent interpretive products have been produced under Commonwealth Government programmes, including: the Offshore Energy Security Program (2006-2011); the Marine Biodiversity Hub under the Commonwealth Environmental Research Facilities (CERF) and the National Environmental Research Program (NERP), and; the National CO2 Infrastructure Plan (NCIP, 2011-15). Collaborations, such as those facilitated by CERF and NERP, and with the Australian Institute of Marine Science (AIMS), have resulted in further work in the region. Areas of investigation have included the North Perth Basin, Bonaparte Gulf and Timor Sea. Using data from these surveys and other sources, GA is continuing to develop regional-scale seabed datasets, including bathymetry, geomorphology, sediment properties, seabed disturbance and seabed hardness that are publicly available via the internet. A pilot program was started in 2010 to collate and archive environmental data generated by the offshore petroleum industry, with a focus on the North West Shelf. Geoscience Australia is currently undertaking marine surveys to provide seabed environmental information to support assessments of the CO2 storage potential of several offshore sedimentary basins under NCIP. A marine survey over the Browse Basin in May 2013, to be undertaken in collaboration with the AIMS, will acquire high-resolution bathymetry and information on seabed and shallow subsurface geology and ecology. Follow-up surveys are also proposed during 2013-2015. The Browse survey results will be publicly released as a data package integrating existing and the newly acquired seabed data, and in a report to the Department of Resources Energy and Tourism on the CO2 storage potential of selected areas of the Browse Basin.

  • This video explains the concept behind Geoscience Australia's Data Cube, a new way of organising, analysing and managing the large amounts of data collected from Earth Observation Satellites (EOS) studies over time. The Data Cube facilitates efficient data analysis and enables users to interrogate Australia's EOS data from the past and present. It is hoped that the Data Cube will become a useful tool used by remote sensing scientists and data analysts to extract information to support for informing future decision-making and policy development within Australia.

  • <b> Legacy service retired 29/11/2022</b> This is an Open Geospatial Consortium (OGC) web service providing access to Australian onshore and offshore borehole data conforming to the GeoSciML version 4.0 specification. The borehole data includes Mineral Drillholes, Petroleum Wells and Water Bores along with a variety of others types. The dataset has been restricted to onshore and offshore Australian boreholes, and bores that have the potential to support geological investigations and assessment of a variety of resources.

  • The Protocol on Environmental Protection to the Antarctic Treaty (the 'Madrid Protocol') includes provisions to protect areas of biological, scientific, historic, aesthetic or wilderness value. While these provisions have been mostly utilised to protect sites of biological or cultural significance, sites of geological or geomorphological significance may also be considered. To date, only two sites within East Antarctica (Marine Plain, Vestfold Hills and Mount Harding, Grove Mountains), have been declared as Antarctic Specially Protected Areas (ASPA) in recognition of their unique geological or geomorphological significance. Recently, however, Stornes, a peninsula in the Larsemann Hills (Prydz Bay) has been identified as a candidate due to the abundance and diversity of extremely rare granulite-facies borosilicate and phosphate minerals found there. The need for proactive intervention, protection and management of sites of intrinsic geoscientific value is becoming increasingly important. This recent example highlights the growing awareness of the intrinsic scientific value of Antarctic geological features within the AAT, including rare mineral or fossil localities. This awareness is identified within the current Australian Antarctic Science Strategic Plan and emphasises that geosciences can actively contribute to and influence the development of management plans and actively support Australia's commitments to Annex V of the Madrid Protocol. Wider recognition of the geological values achieved by invoking the provisions for area management, including creating the need to obtain the permission of a national authority to enter the area, should also mitigate casual souveniring and accidental or deliberate damage caused by ill-advised construction or other human activity.

  • ESRI Grids of available bathymetry within the bounds of proposed Marine Protected Areas in the Antarctic. Interpolated datasets are also included.

  • This study explored the full potential of high-resolution multibeam data for an automatic and accurate mapping of complex seabed under a predictive modelling framework. Despite of the extremely complex distributions of various hard substrata at the inner-shelf of the study area, we achieved a nearly perfect prediction of 'hard vs soft' classification with an AUC close to 1.0. The predictions were also satisfactory for four out of five sediment properties, with R2 values range from 0.55 to 0.73. In general, this study demonstrated that both bathymetry and backscatter information (from the multibeam data) should be fully utilised to maximise the accuracy of seabed mapping. From the modelled relationships between sediment properties and multibeam data, we found that coarser sediment generally generates stronger backscatter return and that deeper water with its low energy favours the deposition of mud content. Sorting was also found to be a better sediment composite property than mean grain size. In addition, the results proved one again the advantages of applying proper feature extraction approaches over original backscatter angular response curves.

  • In 2010, a network of Marine Protected Areas (MPAs) was proposed for the East Antarctic region. This proposal was based on the best available data, which for the benthic regime consisted chiefly of seabed geomorphology and satellite bathymetry data. Case studies from the East Antarctic region indicate that depth and morphology are important factors in delineating marine benthic communities, particularly on the continental shelf. However, parameters such as sediment composition also show a strong association with the distribution and diversity of benthic assemblages. A better assessment of the nature of benthic habitats within the proposed MPA network is now possible with the incorporation of a compilation of sediment properties and higher resolution bathymetry grids across the East Antarctic region (see Figures A and B). Based on these physical properties, and in combination with the seabed morphology, we can now distinguish a range of distinct habitats, such as deep muddy basins, scoured sandy shelf banks, ruggedly eroded slope canyons and muddy deep sea plains. In this presentation, we assess the types of benthic habitats across the East Antarctic region, and then determine how well the proposed MPA network represents the diversity of habitats across this margin. The diversity of physical environments within the proposed MPAs suggests that they likely support a diverse range of benthic communities which are broadly representative of the surrounding region.

  • To date, a range of methods have been developed and applied to the processing and analysis of underwater video and imagery, in part driven by different requirements. For example, in Australia, the marine science community who are partnered by the National Environmental Research Program (NERP) and funded by the Marine Biodiversity Hub, has developed a national CATAMI (Collaborative and Automated Tools for Analysis of Marine Imagery and video) scheme. Technological advances in recent years have improved the usability and output quality of underwater video and still images used to identify and monitor underwater habitats and structures and as a result, these techniques are more frequently applied to marine studies. So far, a comprehensive review of underwater video and still imagery processing/analysis methods has not been completed, although the number of studies utilising underwater stills and video has increased dramatically. Difficulties in diver limitation and stringent regulations applied to the collection of diver-based imagery and video data from underwater benthic habitats. Therefore, remote sensing methods such as underwater video and still imagery are becoming increasingly pivotal for ground-truthing benthic biological and physical habitats in shallow and deep marine and freshwater habitats and are also providing a permanent archive for future analyses. This review focuses on post-processing observational methods used for underwater video and still image habitat classification and quantification. We summarise the main applications, advantages and disadvantages of video and still imagery scoring methods, and illustrate recent advances in this topic.