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  • Lithostratigraphy, grain sizes and down-hole logs of Site 1166 on the continental shelf, and Site 1167 on the upper slope, are analyzed to reconstruct glacial processes in eastern Prydz Bay and the development of the Prydz trough-mouth fan. In eastern Prydz Bay upper Pliocene-lower Pleistocene glaciomarine sediments occur interbedded with open-marine muds and grade upward into waterlaid tills and subglacial tills. Lower Pleistocene sediments of the trough-mouth fan consist of coarse-grained debrites interbedded with bottom-current deposits and hemipelagic muds, indicating repeated advances and retreats of the Lambert Glacier-Amery Ice Shelf system with respect to the shelf break. Systematic fluctuations in lithofacies and down-hole logs characterize the upper Pliocene-lower Pleistocene transition at Sites 1166 and 1167 and indicate that an ice stream advanced and retreated within the Prydz Channel until the mid Pleistocene. The record from Site 1167 shows that the grounding line of the Lambert Glacier did not extend to the shelf break after 0.78 Ma. Published ice-rafted debris records in the Southern Ocean show peak abundances in the Pliocene and the early Pleistocene, suggesting a link between the nature of the glacial drainage system as recorded by the trough-mouth fans and increased delivery of ice-rafted debris to the Southern Ocean.

  • This document provides a practical solution to the transformation of International Terrestrial Reference Frame (ITRF) coordinates into GDA94 coordinates. GDA94 is coordinate datum based on ITRF92 at the fixed epoch of 1994.0. ITRF coordinates will in general differ from GDA94 coordinates for two main reasons, namely tectonic motion of the Australian landmass and reference frame differences. Tectonic motion of the Australian landmass is approximately 7cm/year in the NNE direction. Differences between the ITRF92 coordinate reference frame and the ITRF2000 are at the several cm in magnitude. A standard 7-parameter transformation can adequately model these differences at the cm level, provided the 7-parameter transformation parameters are regularly updated to reflect the tectonic motion. A slightly more complex 14-parameter transformation (7-parameters + their rates) can be used as a better long-term practical solution to these coordinate transformations. A 14 parameter transformation parameter allow users to map a 7 parameter transformation to any epoch of interest. Users of IGS products please note the following. Since 2 December 2001 all International GPS Service (IGS) Products are aligned to ITRF2000. Users transforming coordinates derived from IGS products after 2 December 2001 are provided with additional high quality transformation parameters that referred to as ITRF2000(IGS). This document provides the 14-Parameter transformations from ITRF2000, ITRF2000(IGS), ITRF97 and ITRF96 to GDA94. This document supersedes version 31.08.2001 of the same title.

  • This dataset maps the geomorphic habitat environments (facies) for 131 New South Wales coastal waterways. The classification system contains 12 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Mangrove, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. Most of the estuaries of New South Wales are under intense land use pressure with approximately 80% of the State's population living near an estuary (NSW Dept of Land and Water Conservation) .

  • This paper gives an interpretation of the continental margin off Willkes Land and Terre Adelie, East Antarctica, concentrating on the transition from continental to oceanic crust. The interpretation is based on the deep-seismic and potential field data acquired under the Australian Antarctic and Southern Ocean Profiling Project in 2001 and 2002.

  • This record describes digital data compilation product, where several individual items are grouped for delivery on single CD-ROM. Content and number of items included in the compilation package can vary, depending on size of the individual items. The contents of this CD-ROM are as follows: Catalog # Title 21173 NTdata, all mapinfo mapsheets

  • This line and peg grid was used by ANCA in its Abbotts Booby Bird surveys. The source of this data was an AutoCad map (abbsite.dwg) on ANCAs Christmas Island PC. The grid probably, in reality, runs along the bulldozed lines of an earlier mining grid (visible on the orthophotographs), but does not plot there when overlaid on the orthophotography. Transformation was based on Autocad® Release 7 maps, also existent on the PC.

  • The Nelson, Zeehan and Apollo regions are three of eleven Broad Areas of Interest identified as possible areas for the establishment of Marine Protected Areas by Environment Australia (with statutory and policy responsibility for MPAs), the National Oceans Office (with responsibility for regional marine plans) and other stakeholders. An assessment of the petroleum prospectivity of the Nelson, Zeehan and Apollo regions was undertaken by Geoscience Australia in order to identify areas with the potential to generate and host hydrocarbon accumulations. The assessment used a risk-based approach whereby factors that controlled the sourcing and trapping of hydrocarbons were assessed based on the likeihood of their presence or absence within a particular region. The level of knowledge and confidence in the risk assessment was also incorporated into the ranking of petroleum prospectivity. These factors were considered along with other geological risks to formulate a classification scheme. This scheme has been applied to Nelson 1B, Zeehan 1C and Apollo 1D BAOIs.

  • This abstract is for an invited presentation at the CRC LEME Advances in Regolith Symposia in Canberra November 2003

  • Proterozoic Granites in Australia crop out over at least 145 000 km2 (Table 1). To assess their metallogenic potential a systematic study was undertaken of all granites as well as the composition of rocks within five kilometres of the granite boundaries (Budd et al., 2001). For the granites, data on the field characteristics (presence of alteration, miarolitic cavities, presence or absence of pegmatites etc) as well as the mineralogical, major and trace element compositions of the granites were compiled. Individual granite plutons were then aggregated into suites and Supersuites on a province basis. Data were also assembled on the mineralogical composition of the host rocks, specifically the presence of reactive minerals such as carbonate, carbon, feldspar, magnetite and hematite. A GIS was constructed of all data, and simply proximity analysis was used to intersect the granite plutons as well as 5 km buffers around each pluton with known mineral deposits and occurrences. The commodities and ore deposit types were recorded around each pluton. Each occurrence was checked to ensure its age was ? the age of the related intrusion. On the basis of similarities between Suites/Supersuites of different provinces nine granite associations were identified based on their chemical characteristics, pressure/temperature conditions in their source region and their associated metallogeny. Due to insufficient data, 8.3% of exposed Australian Proterozoic granites could not be classified (Table 1). The differences between each Association and its metallogeny is believed to be controlled by first order differences in temperature and pressure conditions in their source regions. Second order changes that also influenced metallogeny, are imposed by interaction with their host rocks.