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  • The large tsunami disasters of the last two decades have highlighted the need for a thorough understanding of the risk posed by relatively infrequent but disastrous tsunamis and the importance of a comprehensive and consistent methodology for quantifying the hazard. In the last few years, several methods for probabilistic tsunami hazard analysis have been developed and applied to different parts of the world. In an effort to coordinate and streamline these activities and make progress towards implementing the Sendai Framework of Disaster Risk Reduction (SFDRR) we have initiated a Global Tsunami Model (GTM) working group with the aim of i) enhancing our understanding of tsunami hazard and risk on a global scale and developing standards and guidelines for it, ii) providing a portfolio of validated tools for probabilistic tsunami hazard and risk assessment at a range of scales, and iii) developing a global tsunami hazard reference model. This GTM initiative has grown out of the tsunami component of the Global Assessment of Risk (GAR15), which has resulted in an initial global model of probabilistic tsunami hazard and risk. Started as an informal gathering of scientists interested in advancing tsunami hazard analysis, the GTM is currently in the process of being formalized through letters of interest from participating institutions. The initiative has now been endorsed by UNISDR and GFDRR. We will provide an update on the state of the project and the overall technical framework, and discuss the technical issues that are currently being addressed, including earthquake source recurrence models and the use of aleatory variability and epistemic uncertainty, and preliminary results for a global hazard assessment which is an update of that included in UNIDSDR GAR15.

  • GA publication: Flyer AEIP, ELVIS, EM-LINK 2021

  • Audio-visual materials created from OpenQuake training delivered by the Global Earthquake Model held at Geoscience Australia in September 2014.

  • Following a Government decision in 1984, Geoscience Australia actively engages in nuclear monitoring activities on behalf of the Australian Government through the Department of Foreign Affairs and Trade's Australian Safeguards and Non-proliferation Office. Geoscience Australia helps Australia fulfil its obligations under the CTBT by monitoring for nuclear explosions worldwide and by contributing to the development of the CTBT verification regime. Geoscience Australia is currently responsible for the operation and maintenance of 10 of Australia's seismo-acoustic IMS facilities (six seismic stations, three infrasound stations and one hydroacoustic station). Additionally, Geoscience Australia is in the process of building the final infrasound station to complete Australia's seismo-acoustic IMS network. Construction of this station is expected to be completed within the next two years. Geoscience Australia actively participates in international fora dedicated to technological advances supporting nuclear non-proliferation and verification, and to the use of IMS data for civil and scientific applications. The latter include tsunami-warning and the monitoring of earthquakes and volcanic eruptions.

  • Audio-visual materials created from OpenQuake training delivered by the Global Earthquake Model held at Geoscience Australia in September 2014.

  • Prior to the advent of satellite imagery in the 1970s, extensive use was made of aerial photography to systematically image and capture land information. As part of national mapping and survey campaigns run by its predecessors, Geoscience Australia (GA) is custodian of some 1.2 million aerial photos dating back to 1928. Through these campaigns every part of Australia and its external territories was imaged at some point and often repeatedly over the last 90 years, forming a unique and invaluable historical collection. Most importantly, they enable us to extend the record of surface land changes back an additional 50 years or more. GA is progressively moving this collection from analogue to a modern digital data management framework. Discoverability and access to data are essential to realising the full potential of the collection, and associated flight line diagrams are critical in connecting physical and digitised material in the collection to an accurate location consistent with modern datums. The focus of digitisation has been on scanning film and storing individual frames as photo images. Both flight line diagrams are also being digitised and georeferenced, and information on the film is transcribed into a structured database, which will drive a future catalogue for open online access. Only a subset of the aerial photos have been digitised, based on preservation concerns and specific use-cases. GA also is prototyping a new processing workflow to value-add to the digitised collection by creating products that are readily consumable into geographic information systems and as web services. This work may lead to further investment in digitisation by demonstrating broader utility and continuing collaboration with other stakeholders such as the National Archives of Australia. This will be needed to complete the modernisation vision, As with other historic data remediation, surprising finds have been unearthed, gaps in supporting information identified, and an untapped but largely recognised desire for the data. GA is investigating possible applications of citizen science to aid in the modernisation of this collection. This presentation will look at the process undertaken, the type of data available, and will outline some examples of the data, and future use. <b>ePoster is no longer available for access</b>

  • An important part of the management of Australia's marine resources is mapping the geology beneath the sea floor; as part of this work we must understand and mitigate associated environmental impacts. This multimedia product provides background information on marine seismic surveys and the environment, as well as Geoscience Australia's role in environmental mitigation and research. For further information visit http://www.ga.gov.au/about/projects/m.... About the data visualisation: The visualisation of the seismic survey process is representative of a seismic survey, and does not represent any particular survey performed by a particular party. It is not to scale, and is only intended to convey the basic concepts of marine seismic surveys. Production credits: Script: Robin Swindell, Neil Caldwell, Chantelle Farrar, Andrew Carroll, Rachel Przeslawski Production Management: Chantelle Farrar, Neil Caldwell Edit, Cinematography, Sound: Michael O'Rourke 3D Data Visualisation, Animation: Neil Caldwell, Julie Silec Broadcast Design: Julie Silec Scientific Advice: Andrew Carroll, Rachel Przeslawski, Merrie-Ellen Gunning http://www.ga.gov.au Category Science & Technology License Creative Commons Attribution license (reuse allowed)

  • Bookmark developed during the year of the 30th anniversary of the Newcastle earthquake and used to raise awareness of earthquakes and to provide information on what to do in an earthquake. As Geoscience Australia jointly operates the Joint Australian Tsunami Warning Centre with the Bureau of Meteorology, the bookmark also provides information on tsunami safety. Geoscience Australia identifies and characterises potentially tsunamigenic earthquakes and this information is used to initiate the tsunami warning chain.

  • <p>Lu-Hf isotopic analysis of zircon is becoming a common way to characterise the source signature of granite. The data are collected by MC-LA-ICP-MS (multi-collector laser ablation inductively coupled plasma mass spectrometry) as a series of spot analyses on a number of zircons from a single sample. These data are often plotted as spot analyses, and variable significance is attributed to extreme values, and amount of scatter. <p>Lu-Hf data is used to understand the origin of granites, and often a distribution of εHf values is interpreted to derive from heterogeneity in the source or from mixing processes. As with any physical measurement, however, before the data are used to describe geologic processes, care ought to be taken to account for sources of analytical variability. The null hypothesis of any dataset is that there is no difference between measurements that cannot be explained by analytical uncertainty. This null hypothesis must then be disproven using common statistical methods. <p>There are many sources of uncertainty in any analytical method. First is the uncertainty associated with the counting statistics of each analysis. This uncertainty is usually recorded as the SE (standard error) uncertainty attributed to each spot. This uncertainty commonly underestimates the total uncertainty of the population, as it only contains information about the consistency of the measurement within a single analysis. The other source of uncertainty that needs to be characterised is similarity over multiple analyses. This is very difficult to assess in an unknown material, but can be assessed by measuring well-understood reference zircons. <p>Reference materials are characterised by homogeneity in the isotope of interest, and multiple analyses of this material should produce a single statistical population. Where these populations display significant excess scatter, manifested as a MSWD value that far exceeds 1, this means that counting statistics are not the sole source of uncertainty. This can be addressed by expanding the uncertainty on the analyses until the standard zircons form a coherent statistical population. This expansion should then be applied to the unknown zircons to accommodate this ‘spot-to-spot-uncertainty’ or ‘repeatability’ factor. This approach is routinely applied to SHRIMP U-Pb data, and here is similarly applied to Lu-Hf data from granites of the northeast Lachlan Orogen. <p>By applying these uncertainty factors appropriately, it is then possible to assess the homogeneity of unknown materials by calculating weighted means and MSWD factors. The MSWD is a measure of scatter away from a single population (McIntyre et al., 1966; Wendt and Carl, 1991). Where the MSWD is 1, the scatter in data points can be explained solely by analytical means. The higher the MSWD, the less likely it is that the data can be described as a single population. Data which disperses over several εHf units can still be attributed to a single population if the uncertainty envelopes of analyses largely overlap each other. These concepts are illustrated using the data presented in Figure 1. Four out of five of the εHf datasets on zircons from granites form statistically coherent populations (MSWD = 0.69 to 2.4). <p>A high MSWD does not necessarily imply that variation is due to processes occurring during granite formation. Although zircon is a robust mineral, isotopic disturbances are still possible. In the U-Pb system, there is often evidence of post-crystallisation ‘Pb-loss’ which leads to erroneously young apparent U-Pb ages. The Lu-Hf system in zircon is generally thought to be more robust than the U-Pb system, but that does not mean that it is impervious to such effects. In the data set presented in Figure 1, the sample with the most scatter in Lu-Hf (Glenariff Granite, εHf = -0.2 ± 1.5, MSWD = 7.20) is also the sample which had the most rejections in the SHRIMP U-Pb data due to Pb-loss. The subsequent Hf analyses targeted only those grains which fell within the magmatic population (i.e., no observed Pb-loss), but the larger volume excavated by laser Hf analysis means that it is likely that disturbed regions of these grains were incorporated into the measurement. This gives an explanation for the scatter that has nothing to do with geological source characteristics. <p>This line of logic can similarly be applied to all types of multi-spot analyses, including O-isotope analyses. While most of the εHf datasets presented here form coherent populations, the O-isotope data are significantly more scattered (MSWD = 2.8 to 9.4). The analyses on the unknowns scatter much more than on the co-analysed TEMORA2 reference zircon. This implies a source of scatter additional to those described above. In addition to the above described sources of uncertainty, O-isotope analysis by SIMS is also extremely sensitive to topography on the surface of the epoxy into which zircons are mounted (Ickert et al., 2008). O isotopes may also be susceptible to post-formation disturbance and so care should also be taken when interpreting O data, before assigning geological meaning. <p>While it is possible for Lu-Hf and O analyses of zircons in granites to reflect heterogeneous sources and/or complex formation processes, it is important to first exclude other sources of heterogeneity such as analytical sources of uncertainty, and post-formation isotopic disturbances.

  • Exploring for the Future is a four-year $100.5 million programme to unveil new resource opportunities in Northern Australia and parts of South Australia. It is being conducted by Geoscience Australia in partnership with state and Northern Territory government agencies, CSIRO, and universities. This initiative, which is due for completion in 2020–2021, has started to deliver a suite of new products to help unveil new resource opportunities in Northern Australia. The programme has three inter-related elements: minerals, energy and groundwater, which collectively aims to: • provide baseline pre-competitive geoscience data to inform and encourage government, industry and community decision making about sustainable resources management to improve Northern Australia’s economic development • attract investment in resource exploration to Northern Australia • deliver an assessment of groundwater resources for irrigated agriculture and community water supplies as well as for mineral and energy development; and an assessment of the potential impacts of those developments. The minerals-focussed projects have been designed with a three-fold programme logic (Figure 1): 1) Northern Australia-wide projects, 2) focussed integrated studies, and 3) generic innovation and method development. The minerals-focussed project activities address a number of the highest and high priority themes identified by the mineral exploration industry in the UNCOVER Roadmap. 1) Northern Australia-wide projects This work programme will develop and use innovative tools and techniques to collect semi-continental a) geological, b) geochemical, and c) geophysical data on an unprecedented scale. The commencement of these projects is focussed on the region between Tennant Creek and Mt Isa (TISA). a) Geological projects Because one person’s cover is another person’s basement, a Northern Australia-wide series of time-based geological maps are being prepared. Building from the national 1:1 M scale Surface Geology Map of Australia, the Cenozoic, Mesozoic, Palaeozoic and Neoproterozoic layers will be successively removed to reveal a series of ‘solid geology’ maps at 1:1M scale. These maps will form the basis for subsequent 3D models and resource assessments. Extensive use is being made of national-scale potential field geophysical data and existing drillhole data. This has the combined effect of calibrating the geological interpretation of the geophysics with known rocks and attributing the interfaces with their actual depth (from drilling or geophysical estimates). Resultant 3D data are being stored in a new database called Estimates of Geological and Geophysical Surfaces (EGGS); this is a national repository for depth-determined geological information from any method (drilling or geophysical estimate). The EGGS’ database will form the depth-control points from which new 3D surfaces will be constructed and imported into a 3D geological model along with uncertainty. A new peak metamorphic map of Australia is also in production, with a subset available for Northern Australia in the first phase. This map is a compilation of quantitative and qualitative estimates of metamorphic conditions across Australia. The maps will provide important constraints on the crustal exhumation and (mineral) preservation history as well as thermo-barometric evolution of Australia. b) Geochemical projects An atlas of the surface of Northern Australia, as a subset of the national atlas, is in preparation. Geoscience Australia has time-series LANDSAT data from NASA extending back into the 1980s. Each pixel from each scene has been organised in Digital Earth Australia (DEA) so the archive can be ‘data-mined’ to extract pixels with the least vegetation and cloud-cover effects. Products of this work will be a new national Bare Earth image along with iron oxide, silica and clay mineral maps of the surface at 25 m resolution. The European Space Agency’s Sentinel 2 satellite system provides global coverage of multispectral earth-observation data at 10 m resolution from these data. A new cloud-free seamless Sentinel 2 national map will be produced at 10 m resolution. A suite of new machine learning codes has been produced in collaboration with DATA61. These codes are being deployed on the national whole rock and surface geochemical datasets to produce national surface maps of the major elements. An isotopic atlas for northern Australia is being prepared, consisting of a suite of map layers including Sm–Nd, Lu–Hf, U–Pb, Ar–Ar and Pb–Pb; it will be delivered in GIS form, and draped on the aforementioned 3D surfaces. In addition, selected age dating of geological units through U–Pb SHRIMP geochronology and various other dating techniques for direct dating of key mineral deposits are being undertaken. c) Geophysical projects The world’s largest airborne electromagnetic (AusAEM) survey and the most extensive long-period magnetotelluric (AusLAMP) survey are well underway. At the time of writing (February 2018), 20 600 line-km of the 60,000 planned AusAEM data have been flown and 155 new AusLAMP stations have been acquired. In addition, a new seismic tomographic velocity model will be constructed from historical earthquake data; these data form the basis of the Australia-wide AusARRAY project. Gravity data are being infilled at higher resolutions in areas where station spacing is >4 km using a mix of ground and airborne gravity and airborne gravity gradiometry. 2) Focused Integrated Studies (TISA) The region between Tennant Creek and Mt Isa (TISA) is the initial focus of all the above-mentioned activities plus a series of additional projects. This vast under cover region lies between the great mining centres of Tennant Creek (Cu, Au) and Mt Isa (Cu, Pb, Zn, Ag). The thickness of cover is variable and the underlying ‘basement’ geology is poorly known. The region lies at a key junction in Australian geology, with north-south striking domains in the east joining east-west and northwest-southeast striking domains in the west. The region showed unexplained base metal anomalism in the National Geochemical Survey of Australia (NGSA) and at depth, it has variable seismic velocity and Moho depths. The programme has collected 782 surface geochemical and 118 groundwater samples to augment the broad-spaced NGSA dataset; laboratory results are being modelled with the first products due for release in March 2018. The AusARRAY project deployed 120 passive seismic recorders that will remain in the TISA region until later this year. Two more deployments are expected in the life of the programme at locations to be confirmed. A total of 2724 ground gravity stations were collected; the data was released in 2017. A total of 1100 km of deep seismic reflection data have been acquired and processed (see Henson this volume), with processed data to be released in March 2018, and interpretation products to follow. The aim of focusing the activities into one region is to provide the best possible suite of data that will be integrated into an assessment of the undercover mineral potential of the TISA region. This assessment and the geological and mineral systems interpretations of the above data will be tested by a stratigraphic drilling programme in 2019. Assessments are underway for basin-hosted base metals (Cu, Pb, Zn) and for iron-oxide-copper-gold mineral systems. The basin assessment will draw on well-established petroleum systems approaches and apply them to these mineral systems. When the programme is complete, the TISA region will arguably be the best imaged and understood piece of lithosphere on the planet. 3) Innovation and Method Development To complement data acquisition, new big data management and data analytical methods, tools and platforms are being developed to maximise data value. Strategic collaborations have been established with world-leading experts at Australian universities and DATA61 to develop a suite of new geoscience-relevant computer codes and products that will be released in open source repositories (GitHub) and be incorporated into the Australian National Virtual Geophysical Laboratory (ANVGL). Given the vast range of activities being conducted, many of which are novel, effort is being made to share the generic lessons. This includes publishing software codes and standard operating procedures as well as developing an Explorer’s Guide for the TISA region that will have generic applicability elsewhere. Particular effort is being made to transfer knowledge and receive feedback from industry through a series of workshops that commenced in 2017. Conclusions Exploring for the Future, an exciting initiative in collaboration with state and NT partners, will: • Assist in securing an ongoing pipeline of new discoveries and help maintain Australia’s position as a major global mineral and energy exporter. • Determine the location, quantity and quality of groundwater resources to inform water management options, including infrastructure development and water banking. • Benefit the Mining Equipment, Technology and Services (METS) sector by drawing on private sector expertise in undertaking data acquisition and analysis.