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  • Executive Summary. During 2-20 February 1998 the SNTD consortium of AGSO, USC, MAFRI, MARBOT and CBL conducted a survey to sample the major sediment types of Moreton Bay and the Brisbane River. The work was conducted to complete the SNTD Tasks. This Final Report discusses data from the February survey, and incorporates data collected on previous surveys (where appropriate) to provide this advanced perspective on sediment -water interactions and fluxes of metabolites,(notably nitrogen and phosphorus) across the sediment water interface. All Tasks for SNTD, S2R2 have been completed. Key findings are summarised below. ? A sedimentary and biogenic framework was developed for the Moreton Bay. Several Bio-geozones were identified from the facies mapping. These are ( including the areas of each): (i) Oceanic sands with seagrasses, 596 km2 (ii) Mixed muds and sands, 1009 km2 (iii) sewage impacted mixed muds and sands of western MB, 170 km2 (iv) Mangrove sediments, 62 km2, and (iv) the Upper and Lower Brisbane River sediments, 8.5 km2. Within each of these zones we identified key processes controlling nutrient concentrations and fluxes across the sediment-water interface. ? Oceanic sands with seagrasses. N fixation rates are highest in seagrass sediments. DIN fluxes (ammonia + nitrogen oxides) fluxes from the sediments to overlying waters are low. Coupled sedimentary nitrification and denitrification is active and efficient (>90%), and these sediments appear to be very efficient recyclers of sedimentary N. Sedimentary nitrification and denitrification are probably enhanced by oxygen fluxes through the root systems of seagrasses. P fluxes are low in seagrass sediments. Sulphate reduction is not important. Bioirrigation to shallow depths is evident. ? Ocean sands with seagrasses and `Lyngbya?. N fixation is low and DIN fluxes from sediments to overlying waters are low.

  • This report contains the presurvey report for AGSO Survey 229, the third survey carried out under the Australian Antarctic and Southern Ocean Profiling Project. The survey will acquire deep-seismic, bathymetry, magnetics and gravity data and will record the in-fill lines to Survey 228, recorded in 2000/01.

  • The Regional Marine Planning process demands that an analysis of the hydrocarbon potential of areas suggested for marine parkes be conducted. What style of analysis is not currently known but one similar to that done for the Regional Forest Agreements should provide a good analogy.

  • Hydroscheme 2001-2004 details the programme of charting and surveying for the Australian Hydrographic Service, RAN, for the three-year period commencing 2001. This edition of the Hydroscheme contains the inaugural Oceanographic Scheme (Oc Scheme) reflecting the Australian Defence Force's requirements for the acquisition, management and production of oceanographic geospatial information.

  • Australia's Identified Mineral Resources is an annual national assessment that takes a long-term view of Australian mineral resources likely to be available for mining. The assessment also includes evaluations of long-term trends in mineral resources, world rankings, summaries of significant exploration results and brief reviews of mining industry developments.

  • Since 2012, Geoscience Australia has been providing spatial support and advice to the Crisis Coordination Centre (CCC) within Emergency Management Australia (EMA) as part of our collaboration with the Attorney-General's Department. The GA Exposure Report was developed to provide timely exposure information for emergency response and decision-making. The Exposure Report is generated by extracting relevant demographic, building, business, agriculture, institution and infrastructure attributes from the National Exposure information System (NEXIS) in an event footprint, geographical boundary or area of interest.