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  • The Stillwell Hills region comprises granulite-facies gneisses which record evidence for multiple episodes of deformation and metamorphism spanning more than 2500 million years. The predominant orthogneiss package (Stillwell Orthogneiss) is thought to represent the margin of an Archaean craton exposed in Enderby Land, some 150 km to the west that was reworked during the late Proterozoic. Younger additions to the crust include Palaeoproterozoic charnockitic gneiss (Scoresby Charnockite) and Meso-Neoproterozoic mafic sills and dykes (Point Noble Gneiss, Kemp Dykes) and felsic pegmatites (Cosgrove Pegmatites). Subordinate supracrustal rocks, including metaquartzite, metapelitic, metapsammitic and calc-silicate gneiss (Dovers Paragneiss, Sperring Paragneiss, Stefansson Paragneiss, Keel Paragneiss, Ives Paragneiss) are intercalated and infolded with the Archaean-Palaeoproterozoic orthogneisses. This Dataset is derived from the map product 'The Geology of the Stillwell Hills, Antarctica' (GEOCAT 72717). This dataset is published with the permission of the CEO, Geoscience Australia

  • The Geology of the Northern Jetty Peninsula GIS dataset contains the shapefiles and tables of the basement geology of the Northern Jetty Peninsula in East Antarctica. This dataset is derived from the map product ‘Geology of Northern Jetty Peninsula, Mac.Robertson Land, Antarctica'. Northern Jetty Peninsula, incorporating Else Platform (~140 km2) and Kamenistaja Platform (~15 km2), represents a mostly ice-free low-lying region located on the western flanks of the Lambert Graben. The region is underlain by granulite-facies Proterozoic gneisses and unmetamorphosed Permian sediments.

  • Magnetic observatories capable of providing long-period results in absolute measures have been operated in Australia and its territories on and off since 1840. As the first such observatory (that at Gottingen, built by Gauss) was erected only eight years earlier, a long tradition has been established in the observational aspects of the science. In 1979 six observatories are operating: one in Papua New Guinea (recently transferred to that countrys Geological Survey), three in Australia, one in the sub-Antarctic, and one in Antarctica. The number and disposition of continental observatories is inadequate. The factors which should be considered in planning any future network are outlined.

  • High-grade metamorphic and felsic igneous rocks from the northern Prince Charles Mountains, East Antarctica, have been characterised geochemically and dated from SHRIMP zircon geochronological data. Around 980 Ma ago, voluminous magmas representing a combination of mantle-derived and intracrustal melts, including orthopyroxene-quartz monzonite (charnockite) on Loewe Massif and granitic and syenitic intrusions on Mount Collins, were emplaced during a regional high-grade tectonothermal event. Garnet leucogneiss sheets on Mount McCarthy, the products of local partial melting, were also emplaced at about this time. The geology of Fisher Massif is exceptional in that a ca 1280-Ma metavolcanic sequence and coeval granodiorite have been metamorphosed only up to the lower amphibolite facies, and intruded by a ca 1020-Ma biotite granite. None of the analysed sarnples shows in its isotopic systematics the effects of 500-Ma events, prominent elsewhere in East Antarctica. Rare inherited components 1850-1900 Ma old were found in some samples. A paragneiss on Mount Meredith yielded 2500- 2800-Ma and 1800-2100-Ma detrital zircon populations.

  • This study presents the first analysis of benthic megafauna and habitats on the Sabrina Coast shelf, East Antarctica, encompassing an area that has been proposed as a Marine Protected Area. Analysis of seabed images indicates that this shelf is comprised of a relatively abundant benthic fauna compared to other parts of the Antarctic shelf, and is dominated by brittle stars, polychaete tubeworms and a range of other sessile and mobile taxa. The distribution of taxa across this shelf is strongly related ( = 0.592) to variations in water depth, latitude, substrate type and the occurrence of phytodetritus. Areas with a high percent cover by phytodetritus are associated with muddy/sandy sediments, with relatively high abundances of mobile holothurians and amphipods, while harder substrates have high abundances of brachiopods, various forms of hard bryozoans, polychaete tubeworms, a range of massive and encrusting sponges and sea whips. Brittle stars, irregular urchins and anemones occur throughout. Variations in substrate type largely reflect the scattered distribution of dropstones, which creates habitat heterogeneity at fine-scales. Several taxa are found only on areas of hard substrate, with most of these taxa showing a broad distribution across the study area, indicating that the density of dropstones is sufficient for most sessile invertebrates to disperse across the region. A few taxa (the hexactinellid sponge Anoxycalyx joubini and branching hydrocorals) show a more restricted distribution. The distribution of hydrocorals may be influenced by their limited dispersal capability, while A. joubini is most likely restricted by water depth. The occurrence of dropstones is associated with significant increases in taxa diversity, abundance and percent biological cover, enhancing the overall diversity and biomass of this ecosystem.

  • Video of the geo-heritage aspects of the rocks of Stornes Peninsula, Larsemann Hills

  • A short article as a side bar in the Australian Antarctic Magazine published by the Australian Antarctic Division. The sidebar article will accompany a longer article by Lt Peter Waring of the Royal Australian Navy survey team that conducted a multibeam survey in Casey Harbour during season 2013-14

  • This study tested and assessed several methods for identifying and describing physical and chemical characteristics of nearshore sediments in East Antarctica. The study emphasised non-destructive techniques that can be used with small volumes of sample. There were three key aims: 1. Provide information about analytical techniques that are non-destructive and can be used on small-volume samples, 2. Apply these techniques to a set of samples where sufficient material is available and compare the results with the outcomes of traditional geochemical techniques, and, 3. Gain additional information on sedimentary processes in the nearshore environment in East Antarctica. Sediment samples from the Antarctic region are especially difficult to collect because of large logistical requirements and are thus highly valuable. Sediment traps are an example of samples with typically small volumes. Such samples provide valuable information about the nature and quantity of marine sediment in the water column and are highly sought after by researchers. By testing characterisation methods on larger samples, this scoping study provides recommendations for analysing small-volume samples, using non-destructive techniques and techniques that can provide additional information to traditional analysis. In this study, laser Raman spectroscopy and infrared spectroscopy were used to provide qualitative mineralogy for calcite, aragonite, and biogenic silica. Microtextural analysis of quartz grains was undertaken with a scanning electron microscope to provide information on the physical transport processes that the sediment has undergone. With this technique we were also able to identify chemical weathering features. Raman spectroscopy is a relatively rapid technique and has simple sample preparation requirements. The technique can target individual grains but can also measure bulk mineralogy. It is a promising technique for distinguishing mineral polymorphs but scope for quantification is limited for multi-component mixtures compared to traditional mineralogical methods like x-ray diffraction (XRD). Infrared spectroscopy is also quick and sample preparation is minimal. The technique requires more sample than will probably be recovered from sediment traps or sediment cores, at least 15 grams. For samples with large proportions of terrigenous sediment, distinguishing biogenic minerals is difficult because of low concentrations. Acquisition of more reference spectra for minerals of interest in marine substrates (particularly biogenic minerals) would be useful for comparing with sample spectra. Microtextural analysis provides detailed information about potential transport processes but sample preparation and analysis is time-consuming when compared to geochemical analysis. The technique is also somewhat destructive as quartz grains need to be cleaned and mounted. We recommend that an absolute minimum of 20 quartz grains is required for microtextural analysis. Microtextural analysis of sediments from near Davis Station suggests reworking of sediments in a subaqueous environment and minimal aeolian transport. There is also evidence of secondary silica precipitation and minor dissolution of quartz grains.

  • Data from surveys along the East Antarctic margin will be presented to provide insights into the diversity and distribution of benthic communities on the continental shelf and slope, and their relationship to physical processes. Seabed video and still imagery collected from the George V shelf and slope and the sub-ice shelf environment of the Amery Ice Shelf indicate that the benthic communities in these regions are highly diverse, and are strongly associated with the physical environment. Variations in seafloor morphology, depth, sediment type and bottom circulation create distinct seabed habitats, such as muddy basins, rugged slope canyons and scoured sandy shelf banks, which are, in turn, inhabited by discrete seabed communities. The infauna dominated muddy basins contrast sharply with the diverse range of filter-feeding communities that occur in productive canyons and rugged inner shelf banks and channels. In the sub-ice shelf environment, differences in organic supply, linked to the circulation patterns, cause distinct differences in the seabed communities. The strong association between benthic communities and seafloor characteristics allows physical parameters to be used to extend our knowledge of the nature of benthic habitats into areas with little or no biological data. Comprehensive biological surveys of benthic communities in the East Antarctic region are sparse, while physical datasets for bathymetry, morphology and sediment composition are considerably more extensive. Physical data compiled within the proposed network of East Antarctic Marine Protected Areas (MPAs) is used to aid our understanding of the nature of the benthic communities. The diversity of physical environments within the proposed MPAs suggests that they likely support a diverse range of benthic communities.

  • Russia and Australia have interacted in Antarctica ever since the discovery of the Antarctic continent in 1820. The Russian ships 'Vostok' and 'Mirny' after they have sighted Antarctica in January 1820 headed to Sydney to wait until the winter was over and stayed in Sydney harbour for a month. Russia, unlike Australia, does not have territorial claims in Antarctica. Notwithstanding with it, the scientific research undertaken by the Russian scientists within the Australian Antarctic Territory has been very extensive for decades. A number of the Russian Antartctic Expeditions have collected high quality marine geophysical data, including seismic data, in the coastal seas of that part of Antarctica. Russian and Australian scientists actively cooperate on interpretation of these geophysical data sets.