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  • The coverage of this dataset is over the Taree region . The C3 LAS data set contains point data in LAS 1.2 format sourced from a LiDAR ( Light Detection and Ranging ) from an ALS50 ( Airborne Laser Scanner ) sensor . The processed data has been manually edited to achieve LPI classification level 3 whereby the ground class contains minimal non-ground points such as vegetation , water , bridges , temporary features , jetties etc . Purpose: To provide fit-for-purpose elevation data for use in applications related to coastal vulnerability assessment, natural resource management ( especially water and forests) , transportation and urban planning . Additional lineage information: This data has an accuracy of 0.3m ( 95 confidence ) horizontal with a minimum point density of one laser pulse per square metre. For more information on the data's accuracy, refer to the lineage provided in the data history .

  • Detrital zircon age patterns are reported for sandstones from the mid-Permian-Triassic part of the accretionary wedge forming the Torlesse Composite Terrane in Otago, New Zealand and from the early Permian Nambucca Block of the New England Orogen, eastern Australia. In Otago, the Triassic Torlesse samples have a major (64%) age group of Permian-Early Triassic components ca. 240, 255 and 280 Ma, and a minor age group (30%) with a Precambrian-early Paleozoic range (ca. 500, 600 and 1000 Ma). In Permian sandstones nearby, the younger group is diminished (30%), and the older group also contains a major (50%) and unusual, Carboniferous group (components at ca. 330-350 Ma). This trend is similar in sandstones from the Nambucca Block, an early Permian extensional basin in the southern New England Orogen, in which Permian zircons are now minor (<20%), and the age patterns are also dominated (40%) by similar Carboniferous age components, ca. 320-350 Ma.

  • The Murray River is known to display great complexity in surface-groundwater interactions along its course, with 'gaining' sections of the river identified as sites of regional saline groundwater system discharges to the river and the adjacent floodplain. In the Lindsay - Walpolla reach of the River Murray, an airborne electromagnetics (AEM) survey acquired in a 20 km 'wide swath along the river, has enabled key elements of the hydrogeological system to be mapped. Electrical geophysical methods (such as AEM) are able to map the extent and thickness of lateral bank infiltration ('flush') zones, due to the contrast between fresh water leaking from the river and brackish to saline groundwater in adjacent sediments. This study found flush zones in the study area to be present relatively continuously to depths of 5-10m in zones of varying width (200m to <4 km). Development of flush zones to greater depths (up to 25 m) is restricted. The River is interpreted as a weakly losing reach of the river system (at the time of the AEM survey). The most extensive flush zones in the study area are associated with locks, weirs and irrigation districts. Salt mobilisation associated with the flush zones at weir pools may be an issue in terms of salt load delivery to the River Murray and floodplain. Reaches of the river where the flush zones are absent and /or significantly constricted, and similar zones in tributary creeks in the adjacent floodplain, are at higher risk of saline groundwater inflows.

  • The Frome airborne electromagnetic (AEM) survey was flown by Geoscience Australia (GA), DMITRE South Australia and an industry consortium led by Callabonna Uranium Ltd. between May and November 2010 using the Fugro Airborne Surveys TEMPESTTM AEM system. The survey covers 95 450 km2 in 32 317 line km, including the entire South Australian Frome Embayment and portions of the Murray Basin and northern Flinders Ranges, Marree and Leigh Creek. The survey was flown at 2.5 km and 5 km line spacing and 100 m flying height, providing low-noise, regional AEM data. Data were inverted using a GA layered earth inversion (GA-LEI) and are freely available from the GA website as point-located ASCII data, georeferenced grids and sections, GOCAD surfaces and ancillary data. Results show that the data can map a range of local and regional features associated with uranium mineralisation. The data map: - Lateral conductivity variations within the Namba Formation indicating changes in the sand:clay ratio reflecting lateral facies changes; - Palaeovalley morphology and distribution in the southern Frome Embayment and NW Murray Basin, adding to knowledge of the Goulds Dam, Honeymoon and Oban uranium deposits and the Olary Creek palaeovalley system. - Potential new palaeovalley systems over the Benagerie Ridge, interpreted using conductivity anomalies associated with palaeovalley thalwegs; - Fault structures controlling the locations of uranium deposits at Beverley and fault-related redox boundaries in the northern Flinders Ranges associated with uranium mineralisation at MacDonnell Creek and Blanchewater; - Buried conductors associated with the Neoproterozoic Tapley Hill Formation and Saddleworth Formation that may host sediment-hosted Cu-U mineral systems. This regional AEM data set reduces risk for uranium exploration by better defining geology and locating potential uranium traps under cover as well as mapping cover thickness for better depth to target information over a wide area.

  • media pack with information on new national datasets, map and book releases related to the IGC.

  • During 2009-11 Geoscience Australia completed a petroleum prospectivity study of the offshore northern Perth Basin as part of the Australian Government's Offshore Energy Security Program. A significant component of the program was the acquisition of a regional 2D reflection seismic and potential field survey GA-310 in 2008/09. Basement in the northern Perth Basin is deep and generally not resolved in the reflection seismic data. This study models the observed gravity in 2.5D along two southwest trending dip-direction reflection seismic transects across WA11-18 to provide insight into the likely sediment thickness and basement topography. Three cases and ten models are examined according to assumptions about possible target depth to basement, and assumptions about Moho depth

  • A review of mineral exploration trends and activities in Australia in 2011.

  • Map produced for CDPP court case - SIEV 141 This map was produced for Grant Boyes on 30 April 2012 & 1 May 2012

  • In 2010 and 2011, the Australian Government released exploration acreage in the Perth, Mentelle and Southern Carnarvon basins off the southwest margin of Australia. This release was underpinned by two new marine geophysical surveys (GA-310 and GA-2476) that were conducted by Geoscience Australia in late 2008 and early 2009 as part of the Australian Government's Offshore Energy Security Program. These surveys acquired a range of pre-competitive geological and geophysical data that included seismic reflection, gravity, magnetic and swath bathymetry measurements, as well as seafloor dredge samples. The new surveys provided a total of about 26 000 line km of new gravity and magnetic data that add to existing data from around 150 previous marine surveys conducted off the southwest margin since 1960. This Record describes the integration and levelling of the new gravity and magnetic data with existing data, both offshore and onshore, to produce a unified gravity and magnetic dataset for use in constraining regional tectonics, basin structure and petroleum prospectivity. Levelling is a key step in processing ship-borne gravity and magnetic data. This process minimises the mistie errors at ship-track cross-overs that arise from factors such as positioning errors, instrument drift and lack of diurnal corrections to magnetic data. Without accounting for these cross-over errors, gridded data can be rendered un-interpretable by artefacts and distortions at line cross-overs.