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The Nolans Bore deposit, located in the Aileron Province of south-central Northern Territory, is an emerging Australian rare earth development. It consists of steeply northwest dipping apatite veins hosted by ~1806 Ma granite gneiss. A preliminary ~1240 Ma U-Pb age for apatite may correspond to a major global period of alkalic magmatism between 1300 and 1130 Ma, including emplacement of the Bayan Obo deposit in China. Low ?Nd and 87Sr/86Sr in the mineralisation is reminiscent of modern EM-1 ocean island basalts and may indicate a link to carbonatitic magmatism. Oxygen isotope thermometry indicates a mineralisation temperature of 410°C, with '18Ofluid of ~8.0'. Fertilisation of the mantle to produce the EM-1 source may relate to subduction associated with convergence along the southern margin of the North Australian Craton.
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Optically stimulated luminescence (OSL) dating of sand sheets provides a chronology of the largest tsunamis in western Thailand over the late Holocene. Four sand sheets deposited by pre-2004 tsunamis were dated by luminescence to 380 ± 50, 990 ± 130, 1410 ± 190 and 2100 ± 260 years ago (at 1-sigma precision). These compare with previous radiocarbon ages of detrital bark high in buried soils (Jankaew et al., 2008), which suggest that the most recent large-scale predecessor to the 2004 tsunami occurred soon after 550-700 cal BP, and that at least three such tsunamis occurred over the past 3000 years. Concordant OSL ages from successive beach ridges (1600 ± 210 to 2560 ± 350 years ago) and tidal flat deposits (2890 ± 390 years ago) provides a set of limiting maximum ages for sand sheet deposition which, when combined with the sand sheet ages, provide a robust average for tsunami recurrence. The ages imply that between 350 to 700 years separates successive tsunamis on the Andaman coast of Thailand with an average tsunami recurrence interval of 550 years. These results show OSL can provide independent estimates of tsunami recurrence for hazard analysis, particularly in areas where suitable material for radiocarbon dating is unavailable.
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This report describes the ornamental stones used in the ground floor foyer of the Geoscience Australia building. There are three ornamental stones used. The flooring tiles are basalt. The 'fault' line through this is a polished norite and the blade walls are covered by a Persian red Travertine. Investigations have established that the basalt and norite are from Australian quarries and the travertine is from an unknown source overseas possibly Italy.
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2004 updated version of Helby, Morgan & Partridge (1987)
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Legacy product - no abstract available
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Canning Basin Chart updated August 2013
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The geological evolution of Australia is closely linked to supercontinent cycles that have characterised the tectonic evolution of Earth, with most geological and metallogenic events relating to the assembly and breakup of Vaalbara, Kenorland, Nuna, Rodinia and Pangea-Gondwana. Australia largely grew from west to east, with two major Archean cratons, the Yilgarn and Pilbara Cratons, forming the oldest part of the continent in the West Australian Element. The centre consists mostly of the largely Paleo-to Mesoproterozoic North and South Australian Elements, whereas the east is dominated by the Phanerozoic-Mesozoic Tasman Element. The West, North and South Australian Elements initially assembled during the Paleoproterozoic amalgamation of Nuna, and the Tasman Element formed as a Paleozoic accretionary margin during the assembly of Gondwana-Pangea. Australia's present position as a relatively stable continent resulted from the break-up of Gondwana. Australia is moving northward toward southeast Asia, probably during the earliest stages of the assembly of the next supercontinent, Amasia. Australia's resources, both mineral and energy, are linked to its tectonic evolution and the supercontinent cycle. Clusters of resources, both in space and time, are associated with Australia's tectonic history and the Earth's supercontinent cycles. Australia's most important gold province is the product of the assembly of Kenorland, whereas its major zinc-lead-silver deposits and iron-oxide-copper-gold deposits formed as Nuna broke up. The diverse metallogeny of the Tasman Element is a product of Pangea-Gondwana assembly and most of Australia's hydrocarbon resources are a consequence of the break-up of this supercontinent.
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As part of Geoscience Australia's 2002-2004 work program, the Petroleum and Marine Division initiated a collaborative study of the Otway Basin (Figure 1) with Primary Industries and Resources SA (PIRSA) and the Department of Primary Industries (DPI), Victoria. The aim of the project was to enhance the petroleum prospectivity of the basin through an improved understanding of depositional systems, integrated petroleum systems analysis and enhanced access to basic datasets critical to the exploration industry. Major project work components included seismic- and well-interpretation to construct a new regional chronostratigraphic framework for the basin (Figure 2), geochemistry and geohistory modelling to document regional petroleum systems elements (Boreham et al ., 2004), and biostratigraphy to refine age-control, biozonations and correlations within the basin (Krassay et al ., 2004). Biostratigraphic work for the Otway Basin Project involved a major program of new sampling, processing and palynological analysis combined with a thorough review of existing biostratigraphic reports and data. Collection, processing and preparation of new samples were conducted in-house by Geoscience Australia staff. New palynological analyses were carried out by Morgan Palaeo Associates on a commercial contract basis. This Record (CD-ROM) contains consultants palynological reports (Microsoft Word) and digital data files as originally submitted (wmf and dex formats) and as updated and standardised (csv format) for over 200 new samples collected from 14 selected Otway Basin wells (Table 1). This Record also contains revised palynological data files (csv format) for 18 Otway Basin wells (Table 2). Revision and updating of palynological data from existing reports and new consultants reports involved initial quality-assurance and quality-control of the data followed by updating of synonyms and systematics to comply with a standardised taxonomy. Revised data files contained in this Record adhere to a standardised taxonomy in current use at Geoscience Australia. Revised data files are presented in a csv format (Excel spreadsheets).
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This entails publishing a formal analysis which, under the International Codes of Zoological and Botanical Nomenclature, must be accompanied by illustrations of specimens. These illustrated specimens can then become the 'ype specimens'. The type specimen acts as a reference upon which the understanding of each species relies. So, if any subsequent research worker wants to compare their material with, or to assign their material to a known species, the concept of that species is dependent on the type specimens and the research worker must refer to those type specimens.
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This collection consists of type specimens, illustrated or referred specimens which have been published in the scientific literature. Type specimens that have been published in literature of a wide variety of different macro and micro fossils. The Commonwealth Palaeontological Collection is a collection of type, illustrated referred or cited specimens of fossils which have been published in the scientific literature. This Collection was initiated by Federal Cabinet decision during the 1920s. When fossil specimens of any new species of animal or plant are found, for it to be of any future use in biostratigraphy, it of course must be analysed.