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  • Geoscience Australia carried out a marine survey on Carnarvon shelf (WA) in 2008 (SOL4769) to map seabed bathymetry and characterise benthic environments through colocated sampling of surface sediments and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wavegenerated currents. Data and samples were acquired using the Australian Institute of Marine Science (AIMS) Research Vessel Solander. Bathymetric mapping, sampling and video transects were completed in three survey areas that extended seaward from Ningaloo Reef to the shelf edge, including: Mandu Creek (80 sq km); Point Cloates (281 sq km), and; Gnaraloo (321 sq km). Additional bathymetric mapping (but no sampling or video) was completed between Mandu creek and Point Cloates, covering 277 sq km and north of Mandu Creek, covering 79 sq km. Two oceanographic moorings were deployed in the Point Cloates survey area. The survey also mapped and sampled an area to the northeast of the Muiron Islands covering 52 sq km. cloates_3m is an ArcINFO grid of Point Cloates of Carnarvon Shelf survey area produced from the processed EM3002 bathymetry data using the CARIS HIPS and SIPS software

  • The Brattstrand Paragneiss, a highly deformed Neoproterozoic granulite-facies metasedimentary sequence, is cut by three generations of ~500 Ma pegmatite. The earliest recognizable pegmatite generation, synchronous with D2-3, forms irregular pods and veins up to a meter thick, which are either roughly concordant or crosscut S2 and S3 fabrics and are locally folded. Pegmatites of the second generation, D4, form planar, discordant veins up to 20-30 cm thick, whereas the youngest generation, post-D4, form discordant veins and pods. The D2-3 and D4 pegmatites are abyssal class (BBe subclass) characterized by tourmaline + quartz intergrowths and boralsilite (Al16B6Si2O37); the borosilicates prismatine, grandidierite, werdingite and dumortierite are locally present. In contrast, post-D4 pegmatites host tourmaline (no symplectite), beryl and primary muscovite and are assigned to the beryl subclass of the rare-element class. Spatial correlations between B-bearing pegmatites and B-rich units in the host Brattstrand Paragneiss are strongest for the D2-3 pegmatites and weakest for the post-D4 pegmatites, suggesting that D2-3 pegmatites may be closer to their source. Initial 87Sr/86Sr (at 500 Ma) is high and variable (0.7479-0.7870), while -Nd500 tends to be least evolved in the D2-3 pegmatites (-8.1 to -10.7) and most evolved in the post-D4 pegmatites (-11.8 to -13.0). Initial 206Pb/204Pb and 207Pb/204Pb and 208Pb/204Pb ratios, measured in acid-leached alkali feldspar separates with low U/Pb and Th/Pb ratios, vary considerably (17.71-19.97, 15.67-15.91, 38.63-42.84), forming broadly linear arrays well above global Pb growth curves. The D2-3 pegmatites contain the most radiogenic Pb while the post-D4 pegmatites have the least radiogenic Pb; data for D4 pegmatites overlap with both groups. Broad positive correlations for Pb and Nd isotope ratios could reflect source rock compositions controlled two components. Component 1 (206Pb/204Pb-20, 208Pb/204-43, Nd -8) most likely represents old upper crust with high U/Pb and very high Th/Pb. Component 2 (206Pb/204Pb -18, 208Pb/204Pb~38.5, -Nd500 -12 to -14) has a distinctive high-207Pb/206Pb signature which evolved through dramatic lowering of U/Pb in crustal protoliths during the Neoproterozoic granulite-facies metamorphism. Component 1, represented in the locally-derived D2-3 pegmatites, could reside within the Brattstrand Paragneiss, which contains detrital zircons up to 2.1 Ga old and has a wide range of U/Pb and Th/Pb ratios. The Pb isotope signature of component 2, represented in the 'far-from-source' post-D4 pegmatites, resembles feldspar Pb isotope ratios in Cambrian granites intrusive into the Brattstrand Paragneiss. However, given their much higher 87Sr/86Sr, the post-D4 pegmatite melts are unlikely to be direct magmatic differentiates of the granites, although they may have broadly similar crustal sources. Correlation of structural timing with isotopic signatures, with a general sense of deeper sources in the younger pegmatite generations, may reflect cooling of the crust after Cambrian metamorphism.

  • This dataset reflects the external boundaries of all native title determination and compensation applications that are currently recognized and active within the Federal Court process. Applications that are non-active (i.e. withdrawn, dismissed, finalised, rejected or combined) are only included as aspatial records for completeness. This is a national dataset with data partitioned by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these for completeness. This dataset depicts the spatial definition of active Claimant and Non-claimant native title determination applications and compensation applications. Where possible these may include internal boundaries or areas excluded. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member where assigned to the application. Applications included on the Schedule of Native Title (Federal Court) include all registered and unregistered applications as well as determined applications that are yet to be finalized. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.

  • Geoscience Australia Flyer prepared for LOCATE14.

  • Studies utilising high-resolution multibeam swath bathymetry datasets to understand the glacial evolution of the previously glaciated Antarctic continental margin are limited, and are particularly meagre for the East Antarctic Continental shelf. Here we present an interpretation of the seafloor geomorphology based on a new swath bathymetry dataset from the shallow-water marine environment of the Windmill Islands, adjacent to the Australian Antarctic research station, Casey. This high resolution (1 m) dataset permits visualisation of geomorphological features preserved on the seafloor in unparalleled detail. The seafloor is dominated by an assemblage of bedrock, glacial and post-glacial features, providing new insight into the behaviour of the ice-sheet in the region during past glacial episodes and its subsequent retreat to present-day conditions. Interpretation of the submarine geomorphology reveals five dominant features: (1) basement fault systems and bedrock `highs (2) meltwater channels, (3) streamlined sub-glacial landforms, (4) moraine ridges and (5) isolated basins and depressions. Distinctive NW-SE trending channels and linear features that represent brittle bedrock fault systems are clearly evident. These sub-parallel basement bedrock faults or joints have been preferentially eroded and widened by glacial action to form narrow channels and preserve typical `U-shaped profiles. A secondary set of SW to WSW trending linear features are characterised by broad eroded channels. The general orientation of the coastline and channels in the region suggest that these linear features fundamentally control the regional coastal and seafloor geomorphology. Regions of bedrock highs, comprised of submarine outcrops of crystalline metamorphic basement, are characterised by complex, rugged and variable topography, forming steep knolls, small shoals and reefs. Numerous channel networks have been incised into crystalline bedrock highs and their meandering nature, orientation and geometry are consistent with meltwater channels formed by subglacial hydrological flow under considerable hydrostatic pressure. They likely formed during a period when the ice-sheet was expanded and grounded over the areas of offshore crystalline bedrock, possibly during the late Pleistocene Glacial Maximum (LGM) or earlier glaciations. Glacial lineations characterised by subdued sub-parallel linear ridges are preserved in basins and appear to have formed from moulding of unconsolidated sediments by overriding ice. The orientation of the lineations are consistent with formation during westward expansion of the Law Dome ice-sheet onto the continental shelf during the LGM. Regular and closely-spaced arcuate moraine ridge sets are preserved mostly within the prominent NW-trending U-shaped channels. These features appear to be a sequence of recessional moraines or push moraine banks recording slow or episodic retreat of channelized valley glaciers or outlet ice-streams which appear strongly controlled by the local bathymetry. There are several enclosed basins and shallow depressions between bedrock highs with varying degrees of post-glacial sedimentary infill. There is little evidence of reworking of sediments by currents and as a result, the glacial features in this dataset are well preserved. Interpretation of submarine glacial landforms using high-resolution swath bathymetry, integrated with existing information of local ice-sheet evolution from terrestrial studies, allows us to enhance our understanding of the ice-sheet dynamics in the Windmill Islands region.

  • This dataset attempts to reflect the boundaries of claimant applications for Native Title as per the Register of Native Title Claims (s185, Native Title Act; Commonwealth). This is a national dataset but data is stored by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these. This dataset depicts the spatial record of registered claimant applications. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member assigned to the application. Applicants of registered applications have the Right To Negotiate (RTN) with respect to certain types of Future Acts over the area being claimed. Whilst applications that are determined are recorded on a separate register, all registered applications remain on the Register of Native Title Claims until otherwise finalised.. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.

  • This dataset attempts to reflect the boundaries of claimant applications for Native Title as per the Register of Native Title Claims (s185, Native Title Act; Commonwealth). This is a national dataset but data is stored by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these. This dataset depicts the spatial record of registered claimant applications. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member assigned to the application. Applicants of registered applications have the Right To Negotiate (RTN) with respect to certain types of Future Acts over the area being claimed. Whilst applications that are determined are recorded on a separate register, all registered applications remain on the Register of Native Title Claims until otherwise finalised. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.

  • This dataset reflects the external boundaries of all native title determination and compensation applications that are currently recognized and active within the Federal Court process. Applications that are non-active (i.e. withdrawn, dismissed, finalised, rejected or combined) are only included as aspatial records for completeness. This is a national dataset with data partitioned by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these for completeness. This dataset depicts the spatial definition of active Claimant and Non-claimant native title determination applications and compensation applications. Where possible these may include internal boundaries or areas excluded. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member where assigned to the application. Applications included on the Schedule of Native Title (Federal Court) include all registered and unregistered applications as well as determined applications that are yet to be finalized. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.

  • This dataset reflects the external boundaries of all native title determination and compensation applications that are currently recognized and active within the Federal Court process. Applications that are non-active (i.e. withdrawn, dismissed, finalised, rejected or combined) are only included as aspatial records for completeness. This is a national dataset with data partitioned by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these for completeness. This dataset depicts the spatial definition of active Claimant and Non-claimant native title determination applications and compensation applications. Where possible these may include internal boundaries or areas excluded. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member where assigned to the application. Applications included on the Schedule of Native Title (Federal Court) include all registered and unregistered applications as well as determined applications that are yet to be finalized. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.

  • This dataset attempts to reflect the boundaries of claimant applications for Native Title as per the Register of Native Title Claims (s185, Native Title Act; Commonwealth). This is a national dataset but data is stored by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these. This dataset depicts the spatial record of registered claimant applications. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member assigned to the application. Applicants of registered applications have the Right To Negotiate (RTN) with respect to certain types of Future Acts over the area being claimed. Whilst applications that are determined are recorded on a separate register, all registered applications remain on the Register of Native Title Claims until otherwise finalised. Geospatial data portraying native title information produced by the National Native Title Tribunal may not be on-sold. Value added products using this data must acknowledge the National Native Title Tribunal as the data source and include the NNTT disclaimer.