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  • Map Index indicating the availability of the Department of Defence produced 50K topographic mapping. Folded copies only which are available free of charge. Product Specifications Coverage: Australia Currency: 2004 (PDF); 2004 (data) Coordinates: Geographical Datum: GDA94 Format: ArcInfo Export, ArcView Shapefile and MapInfo mid/mif; PDF (maps only); Paper Map (maps only) Medium: GIS Data Free online, free folded map or CD-ROM (fee applies) Forward Program: Updated annually

  • The variability in the inherent optical properties along an estuary-coast-ocean continuum in tropical Australia has been studied. The study area, the Fitzroy Estuary and Keppel Bay system, is a shallow coastal environment (depth < 30 m) with highly turbid waters in the estuary and blue oceanic waters in the bay and subject to macrotides. Biogeochemical and inherent optical properties (IOPs) were sampled in the near-surface layer spatially and across the tidal phase during the dry season. These determinations included continuous measurements of spectral absorption, scattering and backscattering coefficients, together with discrete measurements of spectral absorption coefficients of phytoplankton, nonalgal particles and colored dissolved organic matter, and concentrations of phytoplankton pigments and suspended matter. Because of a large variability in the characteristics of the water components on short spatial and temporal scales, we observe a large variability in the associated optical properties. From the estuary to the bay, particle scattering and dissolved absorption decreased by 2 orders of magnitude, and nonalgal particle absorption decreased by 3 orders of magnitude. We also observed a strong variability in particle single scattering albedo and backscattering efficiency (by a factor of 6) and in specific IOPs (IOPs normalized by the relevant constituent concentration) such as suspended matter-specific particle scattering and chlorophyll-specific phytoplankton absorption. Superimposed on this strong spatial variability is the effect of the semidiurnal tide, which affects the spatial distribution of all measured properties. These results emphasize the need for spatially and temporally adjusted algorithms for remote sensing in complex coastal systems.

  • Presented at the Evolution and metallogenesis of the North Australian Craton Conference, 20-22 June 2006, Alice Springs. The Early Mesoproterozoic (1600 Ma - 1570 Ma) was a period of widespread compressional tectonism and high geothermal gradient metamorphism in the Australian Proterozoic. In the eastern half of the North Australian Craton, the bulk of Palaeoproterozoic terrains underwent high-temperature tectonism between 1600 Ma to 1550 Ma. In central Australia, the Chewings Orogeny (1600 Ma - 1570 Ma) was associated with approximately north-south shortening coeval with regional low-pressure high-temperature metamorphism up to granulite grade. In northeastern Australia, the Early Isan (1600 Ma - 1580 Ma), and Ewamin-Janan Orogenies (1585 Ma - 1555 Ma) in the Mt Isa and Georgetown and Yambo Inliers, respectively, were also associated with approximately north-south shortening and high geothermal gradient metamorphism. In the southern Australian Proterozoic, the Olarian Orogeny (1610 Ma - 1585 Ma) in the Curnamona Province was also characterised by high geothermal gradient metamorphism. <p>Related product:<a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=64764">Evolution and metallogenesis of the North Australian Craton Conference Abstracts</p>

  • Annular to crescent-shaped low back scatter SAR slicks over carbonate reefs and shoals in the Timor Sea with slick `feathering', and within the coral spawning period for the region, are interpreted to be caused by a coral spawn event. In contrast, ocean current data and detailed swath bathymetry of the sea floor to the southeast of the coral spawn slicks suggest that elongate repeating slicks in this area are related to current flow over submarine channels. Assessment of these slicks in association with ancillary data, such as bathymetry, current velocities, weather and timing of scene capture allow a more robust interpretation of their origins. Through differentiating coral spawn and bathymetric slicks from oil and other biological slicks in shallow carbonate systems, such as the Timor Sea, petroleum and environmental assessments for these areas can be improved.

  • Presented at the Evolution and metallogenesis of the North Australian Craton Conference, 20-22 June 2006, Alice Springs. The Nolan's Bore LREE/P/U deposit is located at 133° 14' 15"E ,22° 34' 40"S , approximately 135 km NNW of Alice Springs. The deposit was initially located in 1994 by PNC Exploration (Australia) Pty Ltd (Thevissen, 1995) and rediscovered by Arafura Resources NL in 1999 when the REE and phosphate potential of the deposit came to prominence. Current identified mineral resources (Indicated + Inferred, JORC compliant) stand at 18.6 Mt at 3.1% REO, 14% P2O5, and 0.021% U3O8 (Goulevitch, 2006). The deposit is open laterally and at depth. The bulk of the mineralisation is currently restricted to an area about 1500 m × 1100 m in extent, and this may increase if suspected continuity to other fluorapatite outcrops 500-600 m along strike to the SW is confirmed. A fluorapatite band located about one kilometre west of the main deposit does not appear to be linked at shallow depths to the main deposit as mineralisation is absent in the intervening area. <p>Related product:<a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=64764">Evolution and metallogenesis of the North Australian Craton Conference Abstracts</p>

  • The characterisation of benthic habitats based on their abiotic (physical and chemical) attributes remains poorly defined in the marine environment, but is becoming increasingly central in the development of marine management plans in Australia and elsewhere in the world. The current study tested this link between physical and biological datasets for the southern Gulf of Carpentaria, Australia. The results presented were based on a range of physical factors, including the sediment composition (grain size and carbonate content), sediment mobility, water depth and organic carbon flux, and their relationship to the distribution and diversity of benthic macrofauna was tested. The results reveal the importance of process-based indices, such as sediment mobility, in addition to other environmental factors in defining the distribution of the benthic macrofauna. The distribution of the benthic macrofauna changes gradationally across the south-eastern Gulf, associated with changes in the per cent mud and gravel, the seabed exposure and the water depth. Patterns of diversity also reveal the importance of physical processes such as sediment mobility in defining benthic habitats. The species' environment relationships observed at the small scale of the current study are consistent with broader associations observed for other organisms within the Gulf.

  • This map is part of the series that covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 513 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and 110 kilometres from north to south. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. The topographic map and data index shows coverage of the sheets. Product Specifications Coverage: The series covers the whole of Australia with 513 maps. Currency: Ranges from 1995 to 2009. 95% of maps have a reliability date of 1994 or later. Coordinates: Geographical and either AMG or MGA (post-1993) Datum: AGD66, GDA94, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Paper, flat and folded copies.

  • This map is part of the series that covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 513 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and 110 kilometres from north to south. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. The topographic map and data index shows coverage of the sheets. Product Specifications Coverage: The series covers the whole of Australia with 513 maps. Currency: Ranges from 1995 to 2009. 95% of maps have a reliability date of 1994 or later. Coordinates: Geographical and either AMG or MGA (post-1993) Datum: AGD66, GDA94, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Paper, flat and folded copies.

  • The White Elephant 1:7,500 regolith-landform map illustrates the distribution of regolith materials and the landforms on which they occur, described using the RTMAP scheme developed by Geoscience Australia

  • The White Elephant 1:7,500 regolith-landform map illustrates the distribution of regolith materials and the landforms on which they occur, described using the RTMAP scheme developed by Geoscience Australia