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  • This report outlines the level survey completed during the visit to Funafuti, Tuvalu January 2009. This is the third EDM Height Traversing levelling survey of the deep bench mark array in Funafuti, Tuvalu. This is also a repeat survey and on eight previous occasions, from 1993 to 2003 the Tuvalu levelling survey was performed by the National Tidal Centre (NTC) using the Precise Differential Levelling technique. This project is sponsored by the Australian Agency for International Development (AusAID), managed by the Bureau of Meteorology (BOM) and supported by the National Geospatial Reference Systems Project (NGRS), Geospatial Earth Monitoring Division, GEOSCIENCE AUSTRALIA.

  • Palaeoproterozoic magmatic rocks from the Mary Kathleen Fold Belt of the Mount Isa Inlier record different magmatic textures and variations in tectonic strain associated with extension and the development of crustal-scale detachment zones. New SHRIMP U-Pb zircon geochronology for magmatic rocks, combined with field relationships, refine the duration of this extension to between 1780 and 1740 Ma. The initial stages of this tectono-magmatic event are co-incident with mafic magmatism, basin formation and rapid sedimentation of the ~1780-1765 Ma Myally Supersequence of the Leichhardt Superbasin in the adjacent Leichhardt River Fault Trough. The Ballara Quartzite and Corella Formation represent a period of sag phase sedimentation during the later part this event, and facies models, sequence stratigraphic interpretations and detrital zircon geochronology data confirm the time equivalence of these units to the Quilalar Supersequence of the Leichhardt River Fault Trough. These correlations permit the Eastern and Western Successions of the Mount Isa Inlier to be correlated at this time. Locally, the Corella Formation is intruded by 1740 Ma granites, suggesting that at least the lower parts of this package were deposited during the 1780-1740 Ma extensional event. By linking deep crustal extension processes in the Mary Kathleen area with near-surface basin formation in the adjacent Leichhardt River Fault Trough, it is possible to develop crustal-scale architecture models which provide insights into the development and migration of ore-bearing fluids.

  • Over the last 20 years, it has become common practice to treat SIMS measurements of <sup>207</sup>Pb/<sup>206</sup>Pb in zircon as unfractionated. Consequently, uncertainties associated with composite <sup>207</sup>Pb/<sup>206</sup>Pb values are often limited only by population statistics of the weighted mean, and citation of 95% confidence limits of 1- (or less) on Meso- to Paleoarchean mean ages is increasingly commonplace. In such cases, the presence of undiagnosed SIMS instrumental mass fractionation of <sup>207</sup>Pb/<sup>206</sup>Pb of similar magnitude (1-2-) could have serious ramifications for the accuracy of the measured age: in extreme cases, the 'true' <sup>207</sup>Pb/<sup>206</sup>Pb may not even lie within the artificially narrow 95% confidence interval of the measured value. This possibility has important implications for high-precision zircon geochronology via SIMS, and the correlation of Precambrian events. Our previous work has characterized (via ID-TIMS) a Paleoarchean igneous zircon reference material ('OG1'). Its reference <sup>207</sup>Pb/<sup>206</sup>Pb is 0.29907 ± 0.00011 (3465.4 ± 0.6 Ma) for natural (air-abraded) zircon, and 0.29939 ± 0.00012 (3467.1 ± 0.6 Ma) for zircon annealed and chemically abraded using the Mattinson technique. The corresponding reference <sup>206</sup>Pb/<sup>238</sup>U ages are 3440.7 ± 3.2 Ma and 3463.3 ± 3.6 Ma respectively.

  • The southwest corner of Western Australia consists of Protozoic geology with the area undergoing no tectonic activity in the last 40Ma. It has not been glaciated in the last 20Ma and has had a cool dry climate for at least 200ka, thus providing an ideal environment to preserve fault scarps. High resolution DEM data has been used to identify over 50 new features that are thought to be scarps of surface rupturing earthquakes. Half of these scarps have been the subject of some field work with one new feature being fully verified. Using recently developed fault scaling relations the fault length and displacement are used to estimate the magnitude and, in many cases, identifying multiple events. This has been used to generate a neotectonic earthquake catalogue. Non-extended stable continental region (SCR) and extended continental crust (ECC) and have separate catalogues The SCR catalogue is considered to have a magnitude of completeness (Mc) of M6.5 with ~55 earthquakes of M6.5 or greater. The data has typical truncated GR recurrence characteristics, with a slope (b) of 0.9-1.0, between magnitude 6.5 and 6.9, and rapid decrease in recurrence above M6.9. SCR data has an asymptote of M7.2 suggesting a Mmax of M7.1-M7.3. The ECC data has a Mc of M7.2 and has 15 events of this magnitude or greater. The recurrence rapidly decreases above M7.4 with an asymptote of M7.6 suggesting a Mmax of M7.5-M7.7. The large number of SCR events gives us confidence in the proposed Mmax of M7.2.

  • Overview of work program between 2007 to early 2009.

  • This report describes the geology of the area covered by the SKIPTON 1:100 000 sheet area (7522) in western Victoria. Geomorphology, stratigraphy, structure, metamorphism and economic geology of the area are described. Brief outlines of the regional geological setting and geological history are also presented. The Skipton 1:100 000 sheet area comprises an inlier of early Palaeozoic meta-sediments and intrusives, unconformably overlain by surficial Cainozoic sediments and volcanics. The exposed bedrock forms the westernmost part of the Lachlan Fold Belt. Exposed bedrock comprises Cambrian-Ordovician turbidites of the Warrak and Pyrenees Formations of the Saint Arnaud Group. These units were deformed and regionally metamorphosed to low-grade during the Silurian Benambran deformation and later intruded by Devonian fractionated I-type granite plutons. A transgressive fluviatile to marine sequence of Tertiary rocks overlies older units in the centre and west: units distinguished are the White Hills Gravel, Dilwyn Formation, Heytesbury Group and Moorabool Viaduct Sand. Quaternary units cover most of the sheet area and comprise basalt flows and scoria deposits of the Newer Volcanics, and a range of fluvial and lacustrine sediments including: older alluvial terrace deposits; older alluvial and colluvial deposits; colluvial deposits; swamp and lagoonal deposits; stream alluvial deposits; and lunette deposits. Late Pleistocene aeolian clay, the Windgelli Clay, forms a thin veneer over the most of the Palaeozoic rocks and the Newer Volcanics. The previously worked tungsten, gold, bismuth and silver - bearing vein deposit at Pittong is the only metalliferous occurrence known in SKIPTON. However, the area contains more significant nonmetalliferous deposits including the Pittong clay deposit and deposits of sand, granite, basalt, and scoria.

  • This map shows the boundary of the security regulated port for the purpose of the Maritime Transport & Office Security Act 2003. 4 sheets (Colour) September 2009 Not for sale or public distribution Contact Manager LOSAMBA project, PMD

  • Two significant offshore data acquisition surveys along Western Australia's continental margin (AusGeo News 92) were recently completed by Geoscience Australia. They form part of the agency's ongoing collection of fundamental pre-competitive data and information to understand Australia's offshore frontier basins, and assist with planning and management of Australia's marine environments.

  • This dataset reflects the external boundaries of all native title determination and compensation applications that are currently recognized and active within the Federal Court process. Applications that are non-active (i.e. withdrawn, dismissed, finalised, rejected or combined) are only included as aspatial records for completeness. This is a national dataset with data partitioned by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these for completeness. This dataset depicts the spatial definition of active Claimant and Non-claimant native title determination applications and compensation applications. Where possible these may include internal boundaries or areas excluded. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member where assigned to the application. Applications included on the Schedule of Native Title (Federal Court) include all registered and unregistered applications as well as determined applications that are yet to be finalized.

  • This dataset attempts to reflect the boundaries of claimant applications for Native Title as per the Register of Native Title Claims (s185, Native Title Act; Commonwealth). This is a national dataset but data is stored by jurisdiction (State), for ease of use. Applications stored for each jurisdiction dataset include applications which overlap into adjoining jurisdictions as well as applications which overlap with these. This dataset depicts the spatial record of registered claimant applications. Aspatial attribution includes National Native Title Tribunal number, Federal Court number, application status and the names of both the NNTT Case Manager and Lead Member assigned to the application. Applicants of registered applications have the Right To Negotiate (RTN) with respect to certain types of Future Acts over the area being claimed. Whilst applications that are determined are recorded on a separate register, all registered applications remain on the Register of Native Title Claims until otherwise finalised.