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  • This dataset contains species identifications of micro-benthic worms collected during survey SOL4934 (R.V. Solander, 27 August - 24 September, 2009). Animals were collected from the Joseph Bonaparte Gulf with a Smith-McIntyre grab. Specimens were lodged at Northern Territory Museum on the 1 February 2010. Species-level identifications were undertaken by Chris Glasby at the Northern Territory Museum and were delivered to Geoscience Australia on the 7 March 2011. See GA Record 2010/09 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.

  • This system provides magnetic, radiometric, gravity and digital elevation data from Australian National, State and Territory Government geophysical data archives.

  • This paper highlights a number of aspects of petroleum prospectivity assessments along Australia's offshore southwestern margin, with a focus on identification of potential petroleum systems in the unexplored Mentelle Basin and Wallaby Plateau, and constraining the offshore extent of proven petroleum systems in the Perth Basin.

  • part-page item on matters related to Australian stratigraphy. This column discusses terminology used for mafic/ultramafic bodies, and seeks feedback on whether or not 'Igneous Complex' is an adequate term to describe these bodies. Journal ISSN 0312 4711

  • Detrital zircons from 13 Late Mesoproterozoic to Early Neoproterozoic sandstones and two Palaeozoic sandstones from Tasmania were dated in order to improve constraints on depositional ages, to test correlation between Proterozoic inliers, and to characterise source regions. These include successions considered to be the oldest presently exposed in Tasmania. Typical features of the age distributions of the Proterozoic rocks are prominent data concentrations at 1800-1650 Ma and 1450-1400 Ma, and a minor spread of Archaean ages. Statistical testing of the similarity of the age profiles shows that widespread quartzarenaceous samples from the Detention Subgroup, Needles Quartzite and from the Tyennan region are strongly similar, consistent with broad correlation. Relatively large differences are seen between the Detention Subgroup and the conformable, stratigraphically higher Jacob Quartzite, which contains an additional spread of 1300-1000 Ma zircons suggestive of a Grenvillian source. Age profiles of the quartzarenites and quartzwacke turbidites (Oonah Formation and correlatives) cannot be readily differentiated. The Oonah Formation likewise includes samples with and without Grenvillian ages, and there is no 750 Ma zircon population that would be expected if the turbidites were genetically related to the Wickham Orogeny. The simplest interpretation is that the quartzarenites (Rocky Cape Group and correlatives) and the turbidites (Oonah Formation and correlates) are lateral equivalents, although a younger (post-Wickham Orogeny) age for the Oonah Formation cannot be discounted. A maximum age of ca 1000 Ma is inferred for the Oonah Formation, Rocky Cape Group and correlatives. A minimum age of ca 750 Ma is provided by the basal age of the overlying Togari Group and correlatives. In a metasediment from western King Island, the youngest detrital zircons are ca 1350 Ma, allowing a pre-Grenvillian depositional age as suggested by previous dating of metamorphic monazite. However, the age profile of this sample is not dissimilar to the other Tasmanian successions that are inferred to be 1000-750 Ma. The Wings Sandstone, of southern Tasmania, contains an unusual profile dominated by Grenvillian ages, consistent with an allochthonous origin. Basement ages that broadly match the age spectra of the Tasmanian Proterozoic sediments are found in southwestern Laurentia, consistent with mutual proximity in Rodinia reconstructions. The Palaeozoic sandstones, from the turbiditic Mathinna Supergroup of northeastern Tasmania, have zircon age profiles typical of the Lachlan Fold Belt, with a predominant latest Neoproterozoic-Early Cambrian component and a lesser, broad Proterozoic data concentration at ca 1000 Ma. Western Tasmania was not a significant part of the source area for these rocks.

  • When considering structural design with regard to wind loading, the Australian building code through the Australia/New Zealand Wind Actions Standard (AS/NZS 1170.2, 2002) as well as the wind engineering community in general, relies to a significant extent on the peak wind gust speed observations collected over more than 60 years by the Bureau of Meteorology (BoM). The wind-loading performance of our infrastructure (resilience) is based primarily on the Dines anemometer interpretation of the peak gust wind speed. In the early 1990's BoM commenced a program to replace the aging pressure tube Dines anemometer with the Synchrotac and Almos cup anemometers. This paper presents the results of a reanalysis of the current BoM peak wind gust database for the non-cyclonic region (Region A) of AS/NZS 1170.2 (2002). We compares estimates of the 500-year RP peak wind gust hazard magnitude derived of varying observing record lengths obtained from 31 "Region A" BoM sites. Region A was considered for this initial study as record length would contain a significant number of extreme events (synoptic or thunderstorm) over decadal time scales (i.e. extremes not dominated by one or two tropical cyclone events). To isolate the issue of anemometer replacement, only wind stations located at airports (consistent exposure) and with more than 30 years of record were considered. The methodology was formulated to explore the consistency of peak wind gust measurements due to issues surrounding equipment upgrading. Comparison of results indicated that the recent period (1990-2006) appears to have a reduction in significant events (13 of 31 sites have a mean 500 year RP below the 95% confidence limit for the 500 year RP estimate using the total record). Future plans are to calibrate some existing Dines instruments in-situ in an effort to provide sufficient information to fully specify the dynamic response over the range of operating conditions

  • Regional geology and prospectivity of the Aileron Province in the Alcoota 1:250 000 mapsheet area

  • This map shows the boundaries of the security regulated port for the Maritime Transport & Offshore Security Act 2003. 10 Sheets (Colour) March 2010 Not for sale or public distribution. Contact Manager LOSAMBA project, PMD.

  • Regional airborne electromagnetic (AEM) data provide valuable information for mapping the shallow crust. Data are particularly useful for mapping buried paleotopography including paleovalleys and paleochannels, showing the depth to conductive geological units (and perhaps related faults), and altered and weathered unconformity surfaces, that may be less evident in other regional datasets. Geoscience Australia (GA) has recently acquired and released regional AEM data in the Paterson area of Western Australia, which is one of the most highly prospective areas in Australia. GA is currently in the process of assessing the potential of basinal fluid-related uranium systems in the area, including unconformity-related, sandstone-hosted and calcrete-hosted systems. Interpretation uses this key dataset, along with other available geological, geophysical and remotely sensed data and publicly available drill hole data, Outputs of this assessment include a number of prospectivity maps for these uranium systems. Preliminary interpretations of the AEM data have identified paleovalleys containing Permian and younger sediments and fluid pathways as aquifers in Permian and younger sediments on-lapping the Rudall Complex, Fortescue Basin and Pilbara Craton. In some places, the AEM data map unconformities of Mesozoic over Permian and Permian over the Neoproterozoic Yeneena and Officer Basins and Mesoproterozoic Rudall Complex. The unconformity surface between the Neoproterozoic Yeneena and Officer Basin sediments over rocks of the Rudall Complex or Pilbara Craton appears poorly defined in the data. The AEM data are opening up new avenues of investigation for uranium systems and have shown the utility of flying regional AEM surveys over highly prospective areas.