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  • A nationally-consistent wave resource assessment is presented for Australian shelf (<300 m) waters. Wave energy and power were derived from significant wave height and period, and wave direction hindcast using the AusWAM model for the period 1 March 1997 to 29 February 2008 inclusive. The spatial distribution of wave energy and power is available on a 0.1° grid covering 110'156° longitude and 7'46° latitude. Total instantaneous wave energy on the entire Australian shelf is on average 3.47 PJ. Wave power is greatest on the 3,000 km-long southern Australian shelf (Tasmania/Victoria, southern Western Australia and South Australia), where it widely attains a time-average value of 25-35 kW m-1 (90th percentile of 60-78 kW m-1), delivering 800-1100 GJ m-1 of energy in an average year. New South Wales and southern Queensland shelves, with moderate levels of wave power (time-average: 10-20 kW m-1; 90th percentile: 20-30 kW m-1), are also potential sites for electricity generation due to them having a similar reliability in resource delivery to the southern margin. Time-average wave power for most of the northern Australian shelf is <10 kW m-1. Seasonal variations in wave power are consistent with regional weather patterns, which are characterised by winter SE trade winds/summer monsoon in the north and winter temperate storms/summer sea breezes in the south. The nationally-consistent wave resource assessment for Australian shelf waters can be used to inform policy development and site-selection decisions by industry.

  • A growing need to manage marine biodiversity at local, regional and global scales cannot be met by applying the limited existing biological data sets. Abiotic surrogacy is increasingly valuable in filling the gaps in our knowledge of biodiversity hotspots, habitats needed by endangered or commercially valuable species and systems or processes important to the sustained provision of ecosystem services. This review examines the utility of abiotic surrogates across spatial scales with particular regard to how abiotic variables are tied to processes which affect biodiversity and how easily those variables can be measured at scales relevant to resource management decisions.

  • Multibeam sonar swath-mapping has revealed small submarine volcanic cones on the northeastern Lord Howe Rise (LHR), a submerged ribbon continent. Two such cones, aligned NNW and 120 km apart, were dredged at 23-24Degrees S. Water depth is about 1150 m nearby: the southern cone rises to 750 m and the northern to 900 m. Volcanic rocks dredged from the cones are predominantly highly altered hyaloclastites with minor basalt. The clasts are mostly intensely altered vesicular brownish glass with lesser basalt, in zeolitic, clayey, micritic or ferruginous cement. Lavas and hyaloclastites contain altered phenocrysts of olivine and plagioclase, and fresh clinopyroxene. The latter have compositions between acmite and Ti-augite, and match well clinopyroxene phenocrysts in undersaturated intraplate basanitic mafic lavas. Interbedded micrites in the volcaniclastics represent calcareous ooze that was deposited with (or later than) the volcanic pile. Foraminifera indicate that the oldest micrite is late Early Miocene (~16 Ma), and that the original ooze was deposited in cool water. Late Miocene to Pliocene micrites, presumed to be later infillings, all contain warm water forms. This evidence strongly suggests that both cones formed in pelagic depths in the Early Miocene. Ferromanganese crusts from the two cones are up to 7 cm thick and similar physically, but different chemically. The average growth rate is 3 mm/m.y.. Copper, nickel and cobalt content are relatively high in the north, but copper does not exceed 0.08 wt %, nickel 0.65% and cobalt 0.25%. The Mn:Fe ratio is high in the south (average 13.7) suggesting strong hydrothermal influence. Such small volcanic cones related to intraplate hotspot-type magmatism may occur in extensive fields like those off southern Tasmania. On Lord Howe Rise, the known small volcanic cones coincide with broad gravity highs in areas of shallow continental basement. The highs probably represent Neogene plume-related magmatism. The thick continental crust may dissipate and spread the magma widely, whereas plumes may penetrate thin oceanic crust more readily and build larger edifices. The correspondence of the ages derived from micropalaeontology and from extrapolating from nearby dated hotspot traces support such a genesis. Accordingly, gravity highs in the right setting may help predict fields of small volcanic seamounts.

  • The dataset provides the spatially continuous data of the seabed gravel content (sediment fraction >2000 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.01 decimal degree resolution raster format. The dataset covers the Australian continental EEZ, including seabed surrounding Tasmania. It does not include areas surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands or Australia's marine jurisdiction off of the Territory of Heard and McDonald Islands and the Australian Antarctic Territory. This dataset supersedes previous predictions of sediment gravel content for the Australian Margin 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 national and regional scales. The dataset may not be appropriate for use at local 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 interpolations updated.

  • This dataset provides the spatially continuous data of the seabed sand content (sediment fraction 63-2000 mm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.01 decimal degree resolution raster format. The dataset covers the Australian continental EEZ, including seabed surrounding Tasmania. It does not include areas surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands or Australia's marine jurisdiction off of the Territory of Heard and McDonald Islands and the Australian Antarctic Territory. This dataset supersedes previous predictions of sediment sand content for the Australian Margin 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 national and regional scales. The dataset may not be appropriate for use at local 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 interpolations updated.

  • This includes collection of core from sonic drilling and soil and water samples from boreholes and surface water. The Core is stored in plastic in core trays (4 x 1m). The water samples are disposed of once analysed.

  • The Australian exclusive economic zone (EEZ) contains1.6 million km2 of submarine plateaus, equal to about 13.8% of the world's known inventory of these features. This disproportionate occurrence of plateaus presents Australia with an increased global responsibility to understand and protect the benthic habitats and associated ecosystems. This special volume presents the results of two major marine surveys carried out on the Lord Howe Rise plateau during 2003 and 2007, during which benthic biological and geological samples, underwater photographs, video and multibean sonar bathymetry data were collected. The benthic habitats present on Lord Howe Rise include hard/rocky substrates covering a small area of volcanic peaks (around 31 km2) and parts of other larger seamounts (eg. the Lord Howe Island seamount) which support rich and abundant epifaunal assemblages dominated by suspension feeding invertebrates. These habitats appear to qualify as ecologically and biologically significant areas under the United Nations Convention on Biological Diversity (CBD) scientific selection criterion 1 (uniqueness or rarity), 4 (vulnerability, fragility, sensitivity or slow recovery) and 7 (naturalness). The collection of papers included in this special volume represents a major advance in knowledge about benthic habitats of the Lord Howe Rise, but also about the ecology of plateaus in general.

  • Map showing all of Australia's Maritime Jurisdiction north of approx 25CS . This includes areas around Cocos (Keeling) Islands and areas west of Christmas Island as well as those contiguous to the continent in the north. Map derived from one of the "Australia's Maritime Jurisdiction Map Series" (GeoCat 71985). Depicting Australia's extended continental shelf approved by the Commission on the Limits of the Continental Shelf in April 2008. Background bathymetry image is derived from a combination of the 2009 9 arc second bathymetry and topographic grid by Geoscience Australia and a grid by W.H.F. Smith and D.T. Sandwell, 1997. Background land imagery derived from Blue Marble, NASA's Earth Observatory. Map size 3m x 2m for Australian Customs and Border Protection Service. (for internal use only - not for publication)

  • GEOMA T is a geological-oceanographic computer modelling project which aims to enhance our understanding of the processes controlling sediment mobilisation on the Australian continental shelf. This report describes tidal and surface ocean swell-wave models and their application to studies of shelf sediment mobilisation. The work has been carried out over the past 2 years by a team of collaborators from AGSO, the University of Tasmania, the Australian Bureau of Meteorology and Kort & Matrikelstyrelsen, Geodetic Division in Denmark. Our models predict that swell wave energy is sufficient to mobilise fine sand (0.1 mm diameter), on at least one occasion during the year March 1997 to February 1998, over 63.5% of the Australian continental shelf. The largest and most powerful waves were able to mobilise fine sand up to a water depth of 148 m in the Great Australian Bight. Tidal currents are capable of mobilising fine sand at least once per semi-lunar cycle (ie. -2 weeks) over about 56.4% of the shelf. Overlaying the wave and tide threshold exceedence maps demonstrates that there are areas on the shelf where one process dominates, some areas where tides and waves are of relatively equal importance and still other areas where neither process is significant. We defined 6 shelf regions of relative wave and tidal energy: zero (no-mobility); waves-only, wave-dominated, mixed, tide-dominated and tides-only. The relative distribution of these regions varies with grain size. Inclusion of estimated mean grain size is being undertaken at the present time and this will enhance the usefulness of the regionalisations. GEOMA T provides a predictive, process-based understanding of the shelf sedimentary system. It helps to explain the distribution patterns of surficial sediments and will probably be useful for mapping biological habitats and communities, although further work is needed to better define these relationships. GEOMA T provides a useful tool that will assist with marine environmental management in general, and with the National Ocean's Office regional marine planning process in particular. It has demonstrated applications to marine engineering projects where shelf sediment mobilisation is of concern and to regional studies of pollution dispersal and accumulation.

  • Australian estuaries and coastal waterways were classified into six subclasses according to the wave-, tide- and river-energies that shape them, and also according to their overall geomorphology. The geomorphic classification confirmed the energy classification. Within this framework: - 17% were classified as wave-dominated estuaries; - 11% were classified as tide-dominated estuaries; - 10% were classified as wave-dominated deltas; and - 9% were classified as tide-dominated deltas Therefore, only ~28% of Australian coastal waterways are actually estuaries. The remainder are delta's (19%), strandplains (~5%), or tidal creeks (~35%). A seventh subclass others (13%) includes: Drowned River Valleys, Embayments and Coastal Lakes/Lagoons/Creeks. Strandplains and Tidal Creeks are indicative of very low river-energy, and their joint dominance in the data set (~40%) reflects the fact that Australia is a dry continent, with relatively little river runoff by world standards.