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  • A dataset for display as a layer in the Australian Mines Atlas. It is compiled from many shapefiles of Aboriginal Land, including: Indigenous Protected areas (from DEWHA), Registered Indigenous Land Use Agreements, (hosted by GA on behalf of the National Native Title Tribunal) Determinations of Native Title, (hosted by GA on behalf of the National Native Title Tribunal) Registered Native Title Claims, (hosted by GA on behalf of the National Native Title Tribunal) Indigenous land, freehold and leasehold (prepared by Peter Richardson at GA in 2009)

  • Old, Flat and Red: the Origins of the Australian Landscape Colin Pain, Geoscience Australia, Lisa Worrall, Geoscience Australia, and Brad Pillans, Research School of Earth Science, Australian National University

  • pH is one of the more fundamental soil properties governing nutrient availability, metal mobility, elemental toxicity, microbial activity and plant growth. The field pH of topsoil (0-10 cm depth) and subsoil (~60-80 cm depth) was measured on floodplain soils collected near the outlet of 1186 catchments covering over 6 M km2 or ~80% of Australia. Field pH duplicate data, obtained at 124 randomly selected sites, indicates a precision of 0.5 pH unit (or 7%) and mapped pH patterns are consistent and meaningful. The median topsoil pH is 6.5, while the subsoil pH has a median pH of 7 but is strongly bimodal (6-6.5 and 8-8.5). In most cases (64%) the topsoil and subsoil pH values are similar, whilst, among the sites exhibiting a pH contrast, those with more acidic topsoils are more common (28%) than those with more alkaline topsoils (7%). The distribution of soil pH at the national scale indicates the strong controls exerted by precipitation and ensuing leaching (e.g., low pH along the coastal fringe, high pH in the dry centre), aridity (e.g., high pH where calcrete is common in the regolith), vegetation (e.g., low pH reflecting abundant soil organic matter), and subsurface lithology (e.g., high pH over limestone bedrock). The new data, together with existing soil pH datasets, can support regional-scale decision-making relating to agricultural, environmental, infrastructural and mineral exploration decisions.

  • This map shows the boundary of the Maritime Security Zones for each port for the purpose of the Maritime Transport & Office Security Act 2003. 1 sheet (Colour) April 2010 Not for sale or public distribution Contact Manager LOSAMBA project, PMD

  • Crust predating 3.0 Ga within the Australian continent has previously been identified only in relatively restricted areas of the Yilgarn and Pilbara Cratons of Western Australia. Here we report the discovery of early Mesoarchean (~3150 Ma) rocks in the eastern Gawler Craton of South Australia. Rocks of broadly Mesoarchean age have been inferred by some authors to exist at depth beneath the Gawler Craton (Creaser and Fanning, 1993; Daly and Fanning, 1993), but no rocks of this age have been identified previously at the surface. The newly identified Mesoarchean granites and gneisses crop out across at least ~20 x 30 km and, on the basis of inherited zircon and Nd-isotopic compositions, are inferred to be present at depth beneath a region of at least ~1500 km2.

  • AAM Hatch was engaged by Geoscience Australia to undertake a LiDAR survey over the BHMAR Phase 2 prject area, for the purpose of producing a DTM and vegetation structure analysis. The survey covers an area of approximately 7856 sqkm of the Lower Darling River, downstream from Wilcannia. LiDAR was acquired from a fixed wing aircraft between 19 June 2009 and 5 August 2009 with a vertical accuracy of 0.15m and horizontal accuracy of 0.25m in coordinated system GDA 94, MGA Zone 54 and vertical datum of AHD. File formats included las format and 1m DTM ESRI Grids in ArcGIS binary grid format. Producing a DTM and vegetation structure analysis for the BHMAR Phase 2 Project area for groundwater monitoring.

  • The gravitational attraction of the Galactic centre leads to the centrifugial acceleration of the Solar system barycentre. It results in secular aberration drift which displaces the position of the distant radio sources. The effect should be accounted for in high-precision astrometric reductions as well as by the corresponding update of the ICRS definition.

  • Abiotic surrogates for marine biodiversity have been identified across multiple ecosystems and vary according to spatial scale, region, habitat, and biodiversity measures. Compared to other regions, our knowledge of the relationships between abiotic and biotic factors in northern Australian waters is limited. As part of the Australian Government's program of collecting pre-competitive regional information on seabed habitats, Geoscience Australia recently collaborated with the Australian Institute of Marine Science to conduct a survey along a representative channel of the Van Diemen Rise in the Joseph Bonaparte Gulf (50 - 250 km off the coast of Darwin). We used a range of methods to collect physical and biological data including multibeam sonar, towed underwater video, oceanographic moorings, sediment sampling, and epibenthic sampling. Depth was a major driver in epibenthic biomass and richness. Sponge and octocoral gardens were common on almost all banks surveyed but rarely found on other geomorphic features, suggesting that biodiversity of epifauna is linked to geomorphology and depth. Infaunal assemblages were extremely diverse in soft sediment plains and correlated to some geochemical factors. Species-level identifications will show whether these biological communities are different across sites and thereby reveal potentially unique habitats in the region. Results from this survey will identify key environmental drivers of biological assemblages in a representative region of the Van Diemen Rise to produce regional-scale information on seabed habitats in northern Australia for resource management purposes.

  • Global climate change is putting Australia's infrastructure and in particular coastal infrastructure at risk. More than 80% of Australians live within the coastal zone. Almost 800,000 residences are within 3km of the coast and less than 6m above sea level. Much of Australia's land transport is built around road and rail infrastructure which is within the threatened coastal zone. A significant number of Australia's ports, harbours and airports are under threat. Australia's coastal zone contains several major cities, and supports agriculture, fisheries, tourism, coastal wetlands and estuaries, mangroves and other coastal vegetation, coral reefs, heritage areas and threatened species or habitats. Sea level rise is one physical effect of rising sea temperatures and is estimated at about 0.146m for 2030 (IPCC 2007) and up to 1.1m for 2100 (Antarctic and Climate Ecosystems CRC). The warming is likely to result in increases in intensity of both extra-tropical and tropical storms (spatially dependent) which are predicted to increase storm surge and severe wind hazard. Beaches, estuaries, coastal wetlands, and reefs which have adapted naturally to past changes in climate (storminess) and sea level over long time scales, now are likely to face faster rates of change. In many cases landward migration may be blocked by human land uses and infrastructure. Adaptation options include integrated coastal zone assessments and management; redesign, rebuilding, or relocation of capital assets; protection of beaches, dunes and maritime infrastructure; development zone control; and retreat plans.

  • Interpretation of the 2006 deep seismic reflection data across the western Lachlan Orogen of southeast Australia have provided important insights into crustal-scale fluid pathways and possible source rocks in the Victorian orogenic gold province. The seismic profiles span three of the most productive structural zones in Victoria: the Stawell, Bendigo and Melbourne zones. Variations in the age and style of gold deposits across the structural zones are reflected by changes in crustal structure and composition, as revealed by the seismic data.