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  • 3D visualisation of the Mount Isa Crustal Seismic Survey

  • Communities and their economic activity rely heavily on critical infrastructure. Utility infrastructure facilities are usually comprised of a range of interconnected components characterised by varying degrees of operational criticality and vulnerability to earthquake ground motion. The severity of damage to these components in an earthquake has complex implications for post-event functionality, repair cost and recovery timeframe of facilities. This paper describes how an integration of physical component vulnerability, associated component functionality and a system model of the facility have been used to understand the seismic vulnerability and mitigation opportunities associated with a thermal power station. System behaviour of the facility has been analysed using a network model to evaluate facility performance and to assess component criticality. An application has been developed that integrates these elements in a Monte Carlo simulation that enables the outcomes of a broad set of events to be assessed, and is used to develop facility level fragility models. Finally, the benefits of this approach to the process of assessment of vulnerability of legacy assets and identification of mitigation opportunities are demonstrated.

  • The purpose of this study is to determine the potential of tsunami inundation from historical and potential submarine mass failures of the NSW coast based on the findings from the October 2006 Continental Slope Survey conducted by GA. The learnings from this study are intended for use by the Australian Tsunami Warning Project and NSW emergency managers.

  • <p>The footprint of a mineral system is potentially detectable at a variety of scales, from the ore deposit to the Earth’s crust and lithosphere. In order to map these systems, Geoscience Australia has undertaken a series of integrated studies to identify key regions of mineral potential using new data from the Exploring for the Future program together with legacy datasets. <p>The recently acquired long-period magnetotellurics (MT) data under the national-scale AusLAMP project mapped a lithospheric scale electrical conductivity anomaly to the east of Tennant Creek. This deep anomaly may represent a potential source region for mineral systems in the crust. In order to refine the geometry of this anomaly, high-resolution broadband and audio MT data were acquired at 131 stations in the East Tennant region and were released in Dec 2019 (http://dx.doi.org/10.26186/5df80d8615367). We have used these high-resolution MT data to produce a new 3D conductivity model to investigate crustal architecture and to link to mineral potential. The model revealed two prominent conductors in the resistive host, whose combined responses link to the deeper lithospheric-scale conductivity anomaly mapped in the broader AusLAMP model. The resistivity contrasts coincide with the major faults that have been interpreted from seismic reflection and potential field data. Most importantly, the conductive structures extend from the lower crust to near-surface, strongly suggesting that the major faults are deep penetrating structures that potentially act as pathways for transporting metalliferous fluids to the upper crust where they can form mineral deposits. Given the geological setting, these results suggest that the mineral prospectivity for iron oxide copper-gold deposits is enhanced in the vicinity of the major faults in the region. <p>This release package includes the 3D conductivity model produced using ModEM code in sGrid format and Geo-referenced depth slices in .tif format.

  • As part of Geoscience Australia’s Exploring for the Future Program, Broadband and Audio Magnetotelluric (MT) data were acquired at 131 stations in the East Tennant region, Northern Territory, in 2019. This survey aimed to characterise major crustal structures, to map cover thickness to assist in stratigraphic drill targeting, and to help understand mineral potential in the region. The data package was released in December 2019 (http://dx.doi.org/10.26186/5df80d8615367) and the 3D resistivity model was released in March 2020 (https://pid.geoscience.gov.au/dataset/ga/135011). We applied a probabilistic approach to inverting high-frequency MT data for cover thickness estimation using the 1D Rj-McMCMT code, newly developed in Geoscience Australia. The inversion employs multiple Markov chains in parallel to generate an ensemble of millions of resistivity models that adequately fit the data given the assigned noise levels. The algorithm uses trans-dimensional Markov chain Monte Carlo techniques to solve for a probabilistic resistivity-depth model. Once the ensemble of models is generated, its statistics are analysed to assess the posterior probability distribution of the resistivity at any particular depth, as well as the number of layers and the depths of the interfaces. This stochastic approach gives a thorough exploration of the model space and a more robust estimation of uncertainty than deterministic methods allow. This release package includes the results of probabilistic inversion of Audio Magnetotelluric data at the 131 stations. They can be used to estimate cover thickness for drill site planning, and to map the base of geological basins in the region. Model data files are large, but can be made available on request to clientservices@ga.gov.au.

  • A 3D map of the Cooper Basin region has been produced over an area of 300 x 450 km to a depth of 20 km. The 3D map was constructed from 3D inversions of gravity data using geological data to constrain the inversions. It delineates regions of low density within the basement of the Cooper/Eromanga Basins that are inferred to be granitic bodies. This interpretation is supported by a spatial correlation between the modelled bodies and known granite occurrences. The 3D map, which also delineates the 3D geometries of the Cooper and Eromanga Basins, therefore incorporates both potential heat sources and thermally insulating cover, key elements in locating a geothermal play. This study was conducted as part of Geoscience Australia's Onshore Energy Security Program, Geothermal Energy Project.

  • The depth to Proterozoic basement surface was constructed in order to delineate the thickness of Phanerozoic and more recent cover material. The "basement" refers to the Neoproterozoic and older rocks underlying the Canning Basin. The 3D surface was constructed using GoCad software and constrained by drill-hole data, Euler depth solutions and forward modelling using magnetic data, and interpreted depths from three seismic lines crossing the Waukalycarly Embayment. The depth to basement surface should be used as a guide. With the exception of the drill-hole data, there are uncertainties involved in estimating the depths based on the magnetic methods (Euler depth solutions and forward modelling), as well as the seismic data.

  • The aim of this document is to * outline the general process adopted by Geoscience Australia in modelling storm surge inundation for projects conducted in collaboration with Australian and State Government planning agencies * allow discoverability of all data used to generate the products for the collaborative projects as well as internal activities

  • The aim of this document is to * outline the information management process for inundation modelling projects using ANUGA * outline the general process adopted by Geoscience Australia in modelling inundation using ANUGA * allow a future user to understand (a) how the input and output data has been stored (b) how the input data has been checked and/or manipulated before use (c) how the model has been checked for appropriateness

  • This product is a rendered 3D model of one of the five ACT fossil emblem candidates, the graptolite Monograptus exiguus. The format of the file is ply. or Polygon File Format, and it is designed to store 3D data. The model requires no post-scanning manipulation as it is already complete. The purpose of this is to make this file format publicly available to local school communities so they can 3D print the fossil emblems themselves and engage students with Earth science related topics. <b>Acknowledgement:</b> Computed Tomography (CT) Scans and models generated at <a href="https://ctlab.anu.edu.au/">CTLab</a> - National Laboratory for X-Ray Micro Computed Tomography, Research School of Physics, The Australian National University (ANU), Canberra.