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  • Geoscience Australia's $58.9M 5-year Onshore Energy Security Program began in 2006 and includes a new Geothermal Energy Project. The Project aims to assist in the development of a geothermal industry in Australia by: providing precompetitive geoscience information, including acquisition of new data; informing the public and government about Australia's geothermal potential; and partnering with industry in international promotional events for the purpose of attracting investment. This abstract gives a brief summation of activities undertaken by Geoscience Australia within the Onshore Energy Security Program, principally those of the Geothermal Energy Project.

  • Knowledge of the degree of damage to residential structures expected from severe wind is used to study the benefits from adaptation strategies developed in response to expected changes in wind severity due to climate change, inform the insurance industry and provide emergency services with estimates of expected damage. A series of heuristic wind vulnerability curves for Australian residential structures has been developed for the National Wind Exposure project. In order to provide rigor to the heuristic curves and to enable quantitative assessment to be made of adaptation strategies, work has commenced by Geoscience Australia in collaboration with James Cook University and JDH Consulting to produce a simulation tool to quantitatively assess damage to buildings from severe wind. The simulation tool accounts for variability in wind profile, shielding, structural strength, pressure coefficients, building orientation, building weights, debris damage and water ingress via a Monte Carlo approach. The software takes a component-based approach to modeling building vulnerability. It is based on the premise that overall building damage is strongly related to the failure of key connections and members. If these failures can be ascertained, and associated damage from debris and water penetration reliably estimated, scenarios of complete building damage can be assessed. This approach has been developed with varying degrees of rigor by researchers around the world and is best practice for the insurance industry. This project involves the integration of existing Australian work and the development of additional key components required to complete the process.

  • Gold Coast 2009 LiDAR survey was captured over the Gold Coast City Council region between 25th March and 9th June 2009. The data was acquired by AAM Hatch (now AAMGroup) and funded by Queensland and Commonwealth governments. The data is licensed for use by all Commonwealth, State and Local Government. Data acquisition and post-processing has been controlled to achieve a vertical accuracy within 0.15m (RMS, 68% CI) and horizontal accuracy within 0.45 m. Horizontal coordinates are based upon Map Grid of Australia (MGA) Zone 56 projection. Vertical coordinates are referenced to Australian Height Datum (AHD). The data was captured with point density of 2.5 points per square metre and the data is available as mass point files (ASCII, LAS) and ESRI GRID files with 1m grid spacing in 1km tiles. The data are available as a number of surface types, products and formats including: mass points, digital elevation model (DEM) and hydrologically enforced DEM (HDEM) for the low lying coastal areas. Gold Coast DEM forms part of the Gold Coast HDEM which is a combination of the Redland 2009 LiDAR, Gold Coast 2009 LiDAR and Logan 2009 LiDAR survey areas.

  • This job was part of the Coastal capture program. It captures from the coast to the 10m contour interval for the Yarrahapinni AOI.

  • Based on the analysis of the ETOPO1 data set, this study has identified 5,849 separate large submarine canyons in the world ocean. As has been observed by earlier workers, this study confirms a relationship exists between canyon slope and canyon spacing (increased canyon slope implies closer canyon spacing). The greatest canyon spacing occurs in the Arctic and the Antarctic and canyons are more closely spaced in the Mediterranean than in other areas. River-associated, shelf-incising canyons are significantly more common on active continental margins (119) than on passive margins (34). They are most common on the western margins of South and North America where they comprise 11.7% and 8.6% of canyons respectively, but are absent from the margins of Australia and Antarctica. Active continental margins contain over 50% more canyons (3,605) than passive margins (2,244) and the canyons are steeper, shorter and are more closely spaced on active than on passive margins. Sediment deposits associated with canyons on passive margins are >2.6 kms thick, which is more than 2.5 times the mean value for active margins. Furthermore, there is a correlation between canyon spacing and the thickness of sediments associated with canyons on passive continental margins (canyons are more closely spaced on thickly sedimented passive margins). This observation is consistent with margin evolution as a function of sediment supply and erosion, in which canyon spacing is less for immature passive margins having thick sediment deposits and spacing is greater for more mature passive margins where canyons have been enlarged (and spacing increased) through erosive processes.

  • Stochastic finite-fault ground-motion prediction equations (GMPEs) are developed for the stable continental region of southeastern Australia (SEA). The models are applicable for horizontal-component ground motions for earthquakes 4.0 <= MW <= 7.5 and distances less than 400 km. The models are calibrated with updated source and attenuation parameters derived from SEA ground-motion data. Careful analysis of well-constrained earthquake stress parameters indicates a dependence on hypocentral depth. It is speculated that this is the effect of an increasing crustal stress profile with depth. However, rather than a continuous increase, the change in stress parameter appears to indicate a discrete step near 10 km depth. Average stress parameters for SEA earthquakes shallower and deeper than 10 km are estimated to be 23 MPa and 50 MPa, respectively. These stress parameters are consequently input into the stochastic ground-motion simulations for the development of two discrete GMPEs for shallow and deep events. The GMPEs developed estimate response spectral accelerations comparable to the Atkinson and Boore (BSSA, 2006) GMPE for eastern North America (ENA) at short rupture distances (less than approximately 100 km). However, owing to higher attenuation observed in the SEA crust (Allen and Atkinson, BSSA, 2007), the SEA GMPEs estimate lower ground-motions than ENA models at larger distances. The response spectral models are validated against moderate-magnitude 4.0 <= MW <= 5.3 earthquakes from eastern Australia. Overall the SEA GMPEs show low median residuals across the full range of period and distance. In contrast, Eastern North American models tend to overestimate response spectra at larger distances. Because of these differences, the present analysis justifies the need to develop Australian-specific GMPEs where ground-motion hazard from a distant seismic source may become important.

  • A Dynamic Land Cover Map (DLCM) for Australia has been developed to provide comprehensive and consistent land cover information to inform national and state level priority setting monitoring and reporting for sustainable farming practices, management of water resources, air quality, soil erosion, and forests. The relatively long term time series observations available in the DLCM can be used to assess the land cover dynamics of forests, woodlands, rangelands and cropping systems. The DLCM is based on an analysis of 16-day Enhanced Vegetation Index (EVI) composites collected at a 250-metre resolution using the Moderate Resolution Imaging Spectroradiometer (MODIS) for the period from 2000 to 2008. The MODIS time series for each pixel was analysed using an innovative technique that reduced each time series into 12 coefficients based on the statistical, phenological and seasonal characteristics of each pixel. These coefficients were then clustered and the resultant clusters labelled using Catchment Scale Land Use and the National Vegetation Information System datasets. The classification scheme used to describe land cover categories in the DLCM conforms to the 2007 International Standards Organisation (ISO) land cover standard (19144-2). Land covers including all land and vegetation types are clustered into 34 ISO classes. An accuracy assessment based on around 26,000 independent sites was used to validate the DLCM. As land cover classes are not generally clear-cut, but merge gradually from one to the other, a fuzzy-logic system was used to compare the 34 DLCM classes with the field data on a sliding scale. The match between the field data and the DLCM was exact in 30% of cases, very similar in 35% of cases, moderately similar in 10% of cases, somewhat similar in 18% of cases and a complete mismatch in 7% of cases. These results show a high degree of consistency between the DLCM and the site-based dataset.

  • High voltage transmission towers are key linear assets that supply electricity to communities and key industries and are constantly exposed to wind effects where they traverse steep topography or open terrain. Lattice type high voltage transmission towers are highly optimised structures to minimise cost and reserve strength at design wind speeds (Albermani and Kitipornchai, 2003). The structures are tested under static loading conditions for specified load cases at the design stage. However, the interconnected nature of the lattice towers and conductors present a complex response under dynamic wind loading in service (Fujimura, el.al., 2007). The transmission tower's survival under severe wind and additional load transfer due to collapse of its neighbours is difficult to assess through modelling. Furthermore, the lack of data in the industry doesn't allow for a probabilistic analysis based on history (Abdallah, et.al., 2008). Hence, there is a need for developing an alternative methodology for analysing transmission tower collapse and survival of transmission lines subjected to cyclonic winds utilising design information, limited field data and industry expertise.

  • Australia has been making major progress towards early deployment of carbon capture and storage from natural gas processing and power generation sources. This paper will review, from the perspective of a government agency, the current state of various Australian initiatives and the advances in technical knowledge up until the 2010 GHGT conference. In November 2008, the Offshore Petroleum and Greenhouse Gas Storage Bill 2006 was passed by the Australian Parliament and established a legal framework to allow interested parties to explore for and evaluate storage potential in offshore sedimentary basins that lie in Australian Commonwealth waters. As a result of this Act, Australia became the first country in the world, in March 2009, to open exploration acreage for storage of greenhouse gases under a system that closely mirrors the well-established Offshore Petroleum Acreage Release. The ten offshore areas offered for geological storage assessment are significantly larger than their offshore petroleum counterparts to account for, and fully contain, the expected migration pathways of the injected GHG substances. The co-incidence of the 2009 Global Financial Crisis may have reduced the number of prospective CCS projects that were reported to be in the 'pipe-line' and the paper examines the implications of this apparent outcome. The Carbon Storage Taskforce has brought together both Australian governments technical experts to build a detailed assessment of the perceived storage potential of Australia's sedimentary basins. This evaluation has been based on existing data, both on and offshore. A pre-competitive exploration programme has also been compiled to address the identified data gaps and to acquire, with state funding, critical geological data which will be made freely available to encourage industrial participation in the search for commercial storage sites.