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  • This dataset is a polygon theme of vegetation types or structures of the Cocos (Keeling) Islands. It is derived from topography data (possibly 1:1000 scale) created by AUSLIG. The attributes are probably meaningless. Re-coding according to actual vegetation types is recommended if this layer is to be used for analysis. The vegetation appears to match the 1987 orthophotography, and would therefore be out of date in some areas (the 1992 planning data documentation reveals that areas have been cleared since the 1987 air photos). Coverage is over West and Home Islands.

  • We report the discovery of three submerged, living patch coral reefs covering 80 km2 in the southern Gulf of Carpentaria, Australia, an area previously thought not to contain coral bioherms. The patch reefs have their upper surfaces at a mean water depth of 28.6±0.5 m, and were consequently not detected by satellites or aerial photographs. The reefs were only recognised in our survey using multibeam swath sonar supplemented with seabed sampling and under water video. Their existence points to an earlier, late Quaternary phase of framework reef growth, probably under cooler climate and lower sea level conditions than today. Submerged reefs with surfaces between 20 and 30 m water depth occur in other regions of the Earth and existing bathymetry indicates they could be widespread in the Gulf. Many tropical regions that today do not support patch or barrier reefs for reasons similar to the modern Gulf, may have done so in the past, when environmental conditions were more suitable. Submerged reefs may provide an important refuge for corals during the next few decades when near-surface reefs are threatened by widespread coral bleaching due to warmer global sea surface temperatures.

  • Geoscience Australia, ACRES distribute Landsat Multispectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data for a series of epochs or time frames covering Australia. The first epoch is 1972. These data have been produced and provided by the Australian Greenhouse Office (AGO). AGO use the data in their National Carbon Accounting System for monitoring land clearing and revegetation. This data is only available through ACRES and ACRES Landsat Distributors, and not through the AGO. More information is available at <a href="http://www.ga.gov.au/acres/prod_ser/agosuite.jsp">http://www.ga.gov.au/acres/prod_ser/agosuite.jsp</a> This data is available in 1:1M tiles or as a full continental Mosaic. Tiles areas are available at: <a href="http://www.ga.gov.au/acres/prod_ser/agotilemap.jsp">http://www.ga.gov.au/acres/prod_ser/agotilemap.jsp</a>

  • Product no longer exists, please refer to GeoCat #30413 for the data

  • Product no longer exists, please refer to GeoCat #30413 for the data

  • Product no longer exists, please refer to GeoCat #30413 for the data

  • This dataset contains polygon cadastral data and non-spatial attribute data for the Cocos (Keeling) Islands. Horsburgh Island and North Keeling Atoll are not included in this dataset.

  • This dataset contains points, lines and polygon data of topographical, cultural and infrastructual features. A sample of the Arc View legend that accompanies the above view can be seen here. This dataset covers all of Home Island and most of West Island however the detail is lost outside of the built up areas. The other islands and North Keeling Atoll are not included in this dataset.

  • Recent field observations have identified the widespread occurrence of fluid seepage through the eastern Mediterranean Sea floor in association with mud volcanism or along deep faults. Gas hydrates and methane seeps are frequently found in cold seep areas and were anticipated targets of the MEDINAUT/MEDINETH initiatives. The study presented herein has utilized a multi-disciplinary approach incorporating observations and sampling of visually selected sites by the manned submersible Nautile and by ship-based sediment coring and geophysical surveys. The study focuses on the biogeochemical and ecological processes and conditions related to methane seepage, especially the anaerobic oxidation of methane (AOM), associated with ascending fluids on Kazan mud volcano in the eastern Mediterranean. Sampling of adjacent box cores for studies on the microbiology, biomarkers, pore water and solid phase geochemistry allowed us to integrate different biogeochemical data within a spatially highly heterogeneous system. Geophysical results clearly indicate the spatial heterogeneity of mud volcano environments. Results from pore water geochemistry and modeling efforts indicate that the rate of AOM is 6 mol m-2 year-1, which is lower than at active seep sites associated with conditions of focused flow, but greater than diffusion-dominated sites. Furthermore, under the non-focused flow conditions at Kazan mud volcano advective flow velocities are of the order of a few centimeters per year and gas hydrate formation is predicted to occur at a sediment depth of about 2 m and below. The methane flux through these sediments supports a large and diverse community of micro- and macrobiota, as demonstrated by carbon isotopic measurements on bulk organic matter, authigenic carbonates, specific biomarker compounds, and macrofaunal tissues...