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  • 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>

  • 40Ar/39Ar dating of mica-bearing pyrite from thermally overprinted Archean gold deposits

  • Presented at the Evolution and metallogenesis of the North Australian Craton Conference, 20-22 June 2006, Alice Springs. The King Leopold and Halls Creek Orogens in the Kimberley region of northern Australia are divided into three distinct terranes, each representing a different tectonic setting, that may be part of a larger, diverse collisional orogen on a scale similar to the present Alpine-Himalayan Orogen. Collision with the Kimberley Craton drove intracratonic deformation in the adjacent Tanami and Arunta regions of the North Australian Craton. <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>

  • Bertelli, M., Baker, T., and Cleverley, J., 2006. Geochemical modeling of ore forming processes in skarn deposits.

  • Presented at the Evolution and metallogenesis of the North Australian Craton Conference, 20-22 June 2006, Alice Springs. The North Australian Craton (NAC; Myers et al. 1996) includes Palaeoproterozoic orogens and basins in northern Australia including the Halls Creek, Pine Creek, McArthur, Mount Isa, Tennant Creek, Tanami, and Aileron (northern Arunta) geological regions. Archean basement to the NAC crops out in the Pine Creek and Tanami regions, with ages in the range 2.67 Ga - 2.50 Ga. An early phase of basin development at 2.05-2.00 Ga is reflected in the basal units of the Pine Creek Orogen. The nature of the basement remains unclear across much of the NAC, although geophysical and isotopic evidence suggests widespread presence of thick Neoarchean to Palaeoproterozoic continental crust. Recent work by the Northern Territory Geological Survey and Geoscience Australia , particularly the Arunta and Tanami Regions, has provided important new constraints on the tectonic evolution of the North Australian Craton. Current evidence suggest that most of the NAC was a coherent entity by 1.86-1.83 Ga, when large areas of the craton was covered by thick sedimentary packages which now form regionally important hosts for gold mineralisation. In the Northern Territory, apparent correlations are now possible between packages at 1.865-1.860 Ga (Finniss River and South Alligator Groups, Waramunga Formation, Junalki Formation), 1.84-1.83 Ga (Lander Rock Formation, Killi Killi Formation, lower Ooradidgee Group), and 1.82-1.80 Ga (Ware Group, Hatches Creek Group, Strangways Metamorphic Complex). Tectonism throughout much of the Northern Territory in this period was dominated by intraplate tectonics, although these are likely to have been driven by events at the northern and western margins of the craton, such as the postulated collision between the Kimberley and North Australian Cratons at 1.83 Ga (Sheppard et al. 1999). <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>

  • Geoscience Australia provides information on the nation's future capacity to produce mineral resources. Australia's Identified Mineral Resources is an annual nation-wide assessment of Australia's ore reserves and mineral resources. All major and a number of minor mineral commodities mined in Australia are assessed. Australia's economic demonstrated resources (EDR) of the following mineral commodities increased during 2005 - bauxite, cobalt, diamond (gem and industrial), iron ore, manganese, nickel, rutile, silver, uranium, zinc and zircon. EDR of black coal, copper, gold and tantalum decreased in the same period. EDR for brown coal, magnesite, molybdenum, niobium, platinum group metals, shale oil, and vanadium remained at levels similar to those reported in 2005. Increases in EDR were due to on-going drilling and evaluation of known deposits resulting in the transfer (re-assessment) of resources from inferred or sub-economic categories into EDR, and discoveries of new deposits or extensions of known deposits. A few mining companies re-estimated ore reserves and mineral resources more conservatively, notably in regard to black coal, to comply with the requirements of the Australasian Code for Reporting of Mineral Resources and Ore Reserves (JORC Code).

  • At this scale 1cm on the map represents 1km on the ground. Each map covers a minimum area of 0.5 degrees longitude by 0.5 degrees latitude or about 54 kilometres by 54 kilometres. The contour interval is 20 metres. Many maps are supplemented by hill shading. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours, localities and some administrative boundaries. Product Specifications Coverage: Australia is covered by more than 3000 x 1:100 000 scale maps, of which 1600 have been published as printed maps. Unpublished maps are available as compilations. Currency: Ranges from 1961 to 2009. Average 1997. Coordinates: Geographical and either AMG or MGA coordinates. Datum: AGD66, GDA94; AHD Projection: Universal Transverse Mercator UTM. Medium: Printed maps: Paper, flat and folded copies. Compilations: Paper or film, flat copies only.

  • The Australian Offshore Mineral Locations map shows mineral occurrences and deposits within Australia's 200 nautical mile exclusive economic zone and extended continental shelf. Australia will have one of the largest marine jurisdictions in the world (14.4 million square kilometres) if the United Nations Commission on the Limits of the Continental Shelf agrees to Australia's submission on the outer limit of its extended continental shelf. This is greater than Australia's total land area (13.6 million square kilometres), including Antarctica. The Offshore Mineral Locations map sheds light on the mineral prospectivity in this exciting, but poorly known frontier. It should serve also to ensure mineral values are considered in marine planning and decision making. The Australian Offshore Mineral Locations map draws together data from published and unpublished marine research surveys as well as reports from federal and state government records. Mineral locations shown include manganese nodules and crusts, shellsand, construction aggregate, heavy mineral sand, phosphorites, diamonds, tin, copper, gold and coal. Types of mineralisation, some interpreted from limited information, provide an insight into the nature of the depositional settings. Bathymetry shows the variable physiography of the seafloor that surrounds Australia. For the first time it is possible to identify features such as the contextual setting of manganese crusts and nodules on the East Tasman Plateau and South Tasman Rise, and shellsand and cobalt crust on the edge of the Ceduna Terrace where it descends to the South Australian Abyssal Plain. Insets and images on the map show further detail, mineral specimens and operational aspects associated with exploration and recovery of marine minerals. The map is the result of a collaborative project between Geoscience Australia, CSIRO's Wealth from Oceans Flagship and Division of Exploration and Mining, and each of the State and Northern Territory Geological Surveys. The Australian Offshore Mineral Locations data can be viewed online by using Geoscience Australia's Australian Marine Spatial Information System (AMSIS). AMSIS contains more than 80 layers of Australian marine information which can be viewed and integrated with mineral locations data to create maps to meet specific requirements.

  • This report describes the investigations into the coastal creek system conducted within the Fitzroy agricultural contaminants project. Before this work started there had been only a limited data acquisition on the water quality parameters in several of the coastal creeks carried out by the Queensland Environmental Protection Agency (EPA). These data are a valuable augmentation to the data collected under Coastal CRC auspices. We briefly outline the consolidated dataset, draw qualitative conclusions from it, and develop a conceptual model reflecting the interacting processes. These analyses are then the starting point for the development of a quantitative characterisation of the role of the coastal creeks in the biogeochemistry of Keppel Bay.