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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 .

  • The Tasman Frontier region includes c. 3,000,000 sq km of seabed that is thought to be underlain by crust with continental affinities: the Lord Howe Rise, Bellona Trough, Challenger Plateau, Dampier Ridge, Middleton Basin, Fairway Basin, New Caledonia Trough, Norfolk Ridge System, Reinga Basin, and deep-water parts of Taranaki and Northland basins. We have compiled and interpreted c. 100,000 line km of archival seismic reflection data. Using seismic stratigraphy tied to Deep Sea Drilling Project (DSDP) wells, we identify a tectonic and stratigraphic event that we refer to as the 'Tectonic Event of the Cenozoic Tasman Area' (TECTA). This Middle Eocene to Late Oligocene event involved regional uplift followed by 1-2 km of tectonic subsidence of topographic highs, and >2 km of tectonic subsidence in the New Caledonia Trough. Strata below the TECTA reflector (or seismic unit in some places) are locally folded or reverse faulted. We present seismic-stratigraphic evidence that numerous islands were transiently created by uplift on the Lord Howe Rise during the TECTA event. We suggest that the underlying cause of the TECTA event was initiation of the subduction system that has since evolved into the Tonga-Kermadec system. Note: Abstract for initial submission; acceptance to be confirmed.

  • Introduction: As part of the Offshore Energy Security Program (2007-2011), Geoscience Australia (GA) undertook an integrated regional study of the deepwater Otway and Sorell basins to improve the understanding of the geology and petroleum prospectivity of the region. The under-explored deepwater Otway and Sorell basins lie offshore of southwestern Victoria and western Tasmania in water depths of 100-4,500 m. The basins developed during rifting and continental separation between Australia and Antarctica from the Cretaceous to Cenozoic and contain up to 10 km of sediment. Significant changes in basin architecture and depositional history from west to east reflect the transition from a divergent rifted continental margin to a transform continental margin. The basins are adjacent to hydrocarbon-producing areas of the Otway Basin, but despite good 2D seismic data coverage, they remain relatively untested and their prospectivity poorly understood. The deepwater (>500 m) section of the Otway Basin has been tested by two wells, of which Somerset 1 recorded minor gas shows. Three wells have been drilled in the Sorell Basin, where minor oil shows were recorded near the base of Cape Sorell 1. Structural framework: Using an integrated approach, new aeromagnetic data, open-file potential field, seismic and exploration well data were used to develop new interpretations of basement structure and basin architecture. This analysis has shown that reactivated north-south Paleozoic structures, particularly the Avoca-Sorell Fault System, controlled the transition from extension through transtension to a dominantly strike-slip tectonic regime along this part of the southern margin. Depocentres to the west of this structure are large and deep in contrast to the narrow elongate depocentres to its east. ...

  • Report on the results of using a multibeam sonar to map the Darling River at Menindee

  • Exposure refers to the elements at risk which may be subjected to the impact of severe hazards within a defined geographic area or region. These elements include the built environment, i.e buildings, infrastructure services and utilities, and also population and business activity. Geoscience Australia (GA) is developing the National Exposure Information System (NEXIS) as a national capability to provide an exposure profile to underpin analysis of natural hazards; potential disaster footprints, risk assessments and climate change adaptation research. The NEXIS capability enables modelling to gain a greater understanding of the impact and risk exposure to these events. The information is used to inform evidence based decision making and future planning to aid in the prevention, preparedness, response and recovery to severe hazard events and climate change adaptation. The current NEXIS database provides exposure profile on building type, building construction materials (roof and wall), number of floors, floor area, year built and population demographics, business activity (turnover) and employee numbers. NEXIS is a demonstrated capability used in response to Tropical Cyclone Yasi, Victoria Bushfires, Queensland Floods and other recent national disaster events. The database also provides input data for use with the Earthquake Risk Model (EQRM) and Tropical Cyclone Risk Model (TCRM) to estimate direct and indirect losses to the built environment and possible population casualities. Further development of the database is planned to incorporate infrastructure and facilities data to enhance the capability and availability of nationally consistent data and exposure information.

  • The new Australian geodetic VLBI network operated by the University of Tasmania (UTAS) started regular observations in October, 2010. Three 12-meter "Patriot" radio telescopes are dedicated to the improvement of the celestial and terrestrial reference frames in the southern hemisphere. We present first results from the analysis of an eight-month set of geodetic VLBI data. The data were processed within a global VLBI solution by the least squares collocation method using the OCCAM software. The geodetic positions of the AuScope radio telescopes were estimated with accuracy less than 10 millimetres, and the first sign of their motion due to tectonic plate movement was indicated.

  • Climate change is expected to exacerbate a range of natural hazards in Australia leading to more severe community impacts in the future. There is a need to adapt to a changing hazard environment and increasing community exposure in regions most likely influenced by climate change. Through this paper GA develops a methodology for projecting Australian communities in a spatial sense into the future. The application of this methodology is demonstrated in a case study. In order to address the fact that the impacts of climate change are expected to be more evident in the second half of this century, this model was to extend beyond the 30 year limitation of finer scale population projections, dwelling projections and development plans.

  • Exploration for Unconventional Hydrocarbons in Australia reached a new milestone when Beach Energy announced the first successful flow test of a shale gas target in the Cooper Basin. Significant exploration activity is being seen in the Amadeus, Pedirka and Georgina basins and Beetaloo Sub-basin, while little is known of the potential of many other Central Australian basins. The globally acknowledged large resource potential of coal seam gas, shale and tight gas on the continent in addition to low sovereign risk has put Australia firmly on the radar of many local and international exploration companies. Over the next 12 months Geoscience Australia in collaboration with its counterparts in the State and Territory resource and energy departments will undertake an initial assessment of Australia's unconventional hydrocarbon resource potential. Capitalising on decades of high quality geological data held by the Commonwealth and the States and Territories, the programme aims to compile these data using nationally consistent assessment methodologies that ultimately provide robust figures in an internationally accepted standard. The immediate goal is to provide a first-pass, high level estimate of the likely resource volumes, which will be reported in the second edition of the Australian Energy Resource Assessment (published by RET). The longer term work program aims to assess Australia's onshore basins in terms of their resource potential and provide pre-competitive data to industry. To achieve this, several geological techniques will be applied including, but not limited to, geochemical screening, mapping of source rock occurrences and their distributions as well as physical rock property studies.

  • Traditional aquifer tests are an expensive and time-consuming method for obtaining hydraulic information. Furthermore, in many environments, it is becoming increasingly difficult to obtain environmental clearances to dispose produced waters. In this study, the Nuclear Magnetic Resonance (NMR) method was evaluated to provide data on hydraulic conductivities (K) and transmissivities (T) of sediments within the Darling River Floodplain, Australia. NMR data were acquired every 0.5 m using a slim-hole logging system in 26 sonic cored wells to a depth of ~70 m. KNMR can be estimated from the NMR measurements using the Schlumberger-Doll Research Equation: KNMR = C x ?2 x T2ML2, where is the NMR effective porosity, T2ML is the logarithmic mean of the T2 distributions, and C is a formation factor related to tortuosity. Prior to the calculation of the KNMR, the NMR data were classified into five hydraulic classes ranging from clay to gravely-coarse sand using the core, geophysical, mineralogical, and hyperspectral logs. In selected zones aquifer tests were conducted to provide constraints on the K and T of the formations. Least-squares inversion was used to solve for the optimum C values for each of the hydraulic classes versus the aquifer test obtained T. Comparisons between laboratory permeameter measurements and KNMR indicated correspondence within two orders of magnitude. The borehole NMR method provides a rapid way of estimating the near continuous variations in K through a sedimentary sequence, while also providing useful estimates of K at a scale not achievable using traditional aquifer testing methods.

  • Hydrometeorological events make up or contribute to a majority of disasters in Australia and around the world. Scientists expect climate change will accelerate the frequency and intensity of these events in the future. Information on the location and characteristics of the built and social environment combined with hazard modelling and spatial analysis can facilitate the identification of buildings, people and infrastructure exposed to a particular natural hazard event. This information informs evidence based decision making and future planning to aid in the preparedness, response and recovery to severe hazard events. In Australia, the National Exposure Information System (NEXIS) is a significant national project being undertaken by Geoscience Australia (GA). In 2006 GA embarked on the development of NEXIS in response to the Council of Australian Governments (COAG) reform commitment on Australian's ability to manage natural disasters and other emergencies. The COAG commitment called for the establishment of a 'nationally consistent system of data collection, research and analysis to ensure a sound knowledge base on natural disasters and disaster mitigation' (DOTARS 2002). NEXIS database contains information on buildings, people, businesses and infrastructure and is derived from publicly available demographic, structural, economic and statistical data. Exposure profiles contain information on: building type, size, construction materials, age, replacement costs and population demographics for all residential, commercial and industrial buildings in Australia. Aggregated exposure information underpins risk assessment, emergency management, climate change adaptation, urban planning, insurance industry and research to help assist evidence based decision making. NEXIS development and operationalisation is crucial to support the decision makers and underpins community safety, emergency management and disaster risk reduction initiatives Australia This paper will discuss the development of NEXIS and its application in several national projects with the Department of Climate Change Energy and Efficiency (DCCEE) in Australia and recent national disaster impacts assessments on: Queensland tropical cyclone Yasi, Victoria bushfires and the Queensland floods.