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  • <p>Communities and the economic activity within them rely heavily on critical infrastructure. Utility infrastructure facilities are usually comprised of a range of dissimilar but interconnected components characterised by varying degrees of operational criticality and differing vulnerabilities to earthquake ground motion. The severity of damage to these components in an earthquake has complex implications for facility post-event functionality, repair cost and recovery. 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 vulnerability, criticality and mitigation opportunities associated with a thermal power station and a major substation. <p>In this research a review of published component level models has been conducted and the models were adapted using as-built design information and the engagement of industry expertise. The functionality of facility components for a range of damage states have been assessed along with replacement and repair costs utilising the specialist knowledge of asset managers. Finally, the system behavior of the facilities has been analysed using a network model to evaluate facility behaviour and to assess component criticality. These elements have been integrated in a Monte Carlo simulation using an application called SIRA (System for Infrastructure Resilience Analysis) that enables the outcomes of a broad spectrum of events to be assessed and used to develop facility level fragility models. <p>In this paper the utility of this modelling approach is demonstrated. Comparisons are made with US models in HAZUS that are based on heuristic judgment and the experience in a number of US earthquakes. Finally, the benefits of this approach to assessing the vulnerability of legacy assets and the identification of mitigation opportunities are demonstrated.

  • Total magnetic intensity data measures variations in the intensity of the Earths magnetic field caused by the contrasting content of rock-forming minerals in the Earths crust. The data are collected on airborne geophysical surveys conducted by Commonwealth, State & NT Governments and the private sector.

  • This report presents the results of seabed mapping and habitat classification surveys completed in Darwin Harbour during 2011 and 2013 as part of the Northern Territory Government's marine habitat mapping program. This research aims to provide baseline data on the existing marine habitats and characteristics of the Darwin Harbour region. It is a collaboration between Geoscience Australia (GA), the Australian Institute of Marine Science (AIMS), the Department of Land Resource Management (DLRM) and the Darwin Port Corporation. Key objectives are to: - Produce detailed maps of the bathymetry and derived parameters such as slope and rugosity, - Classify the seabed into areas of hard and soft substrate, and, - Produce seabed habitat maps (or seascapes). Data collection was completed in two stages comprising a multibeam survey, undertaken on the MV Matthew Flinders in 2011 by DLRMs predecessor, the Department of Natural Resources, Environment, the Arts and Sport (NRETAS), GA, AIMS and the Darwin Port Corporation; and, a seabed sampling survey undertaken in 2013 on the MV John Hickman, by DLRM and GA. Data acquired from the surveys included continuous high-resolution multibeam sonar bathymetry and acoustic backscatter, video and still camera observations of seabed habitats and biological communities, and physical samples of seabed sediments. Key outcomes from the surveys include: 1. Improved understanding of the seabed of Darwin Harbour. The main seabed geomorphic features identified in Darwin Harbour include banks, ridges, plains and scarps, and a deep central channel that divides into smaller and shallower channels. Acoustically hard substrates are found mostly on banks and are associated with rocky reef and sponge gardens, and are often overlain by a thin veneer of sandy sediment. In contrast, plains and channels are characterised by acoustically soft substrates and are associated with fine sediments (mud and sand). 2. Classification of physical seabed properties to produce a Seascape Map for Darwin Harbour. Six seascape classes (potential habitats) were derived using an Iterative Self Organising (ISO) unsupervised classification scheme. These six classes are related to statistically unique combinations of seabed substrate, relief, bedform and presence of sediment veneer (quite often inferred from presence of epibenthic biota). The results presented in this report demonstrate the utility of multibeam acoustic data to broadly and objectively characterise the seabed to describe the spatial distribution of key benthic habitats. This is particularly important technique in high-turbidity settings such as Darwin Harbour where the application of satellite and aerial remote sensing techniques can be limited. The results of this study will be used for the planning and analysis of data from upcoming benthic biodiversity studies as they: - Provide robust near-continuous physical variables that can be used to predictive modelling of biodiversity; - Provide high-resolution coverage of near-continuous variables that describe the key physical characteristic of the seabed of the harbour, and; - Enhance survey sample design by providing indicative locations of likely similar biology communities.

  • Coastal communities in Australia are particularly exposed to coincident natural hazards, whereby tropical cyclones and extra-tropical storms cause damage to infrastructure and shorelines from severe wind, flood and storm surge. Because the climatic drivers of severe storms are stronger under certain conditions (e.g. during La Ni±a periods for tropical cyclones), these events can repeatedly impact the coast over periods of weeks to months. Historically, major episodes of beach erosion along southeast Australia have occurred during every decade over the last century, with the most severe in 1974 resulting from two extra-tropical storms in two months. <p>While the process of beach erosion is well understood in general terms, the response of a specific sector of coast to clustered storms may not be. For effective coastal management, this site specific knowledge becomes essential. Here we present a framework for integrating coastal geomorphology and coastal engineering approaches to model shoreline response to clustered storms at a spatial scale that can directly inform management agencies. We focus on two case study areas in southeast Australia, the beaches of the Adelaide metropolitan coast (South Australia) and Old Bar beach (central New South Wales) where erosion is a management priority. <p>For each site we adopt the coastal sediment compartment as the functional management unit, mapped for the Australian continent at multiple spatial scales, and use sub-surface information (boreholes, ground penetrating radar profiles) to estimate sediment volumes in the upper beach to foredune. These data are then used to inform shoreline response modelling linked to an event time series (observed and hind cast) as a separate project component. Future work includes assessment of `at-risk infrastructure at each site. This paper is a contribution to the Bushfire and Natural Hazard Cooperative Research Centre project Storm surge: Resilience to clustered disaster events on the coast.

  • <p>Knowledge of extreme ocean climate is essential for the accurate assessment of coastal hazards to facilitate risk informed decision making in coastal planning and management. Clustered storm events, where two or more storms occur within a relatively short space of time, may induce disproportionately large coastal erosion compared to non-clustered storm events. Therefore this study aims to develop a statistical approach to modelling the frequency and intensity of storm events on the eastern and southern coast of Australia, with a focus on examining storm clustering. This paper presents the preliminary analysis of the recently developed methods and results when they are applied to a study site on the central coast of New South Wales, Australia. This study is a key component of the Bushfire and Natural Hazards CRC Project Resilience to clustered disaster events on the coast storm surge that aims to develop a new method to quantify the impact of coincident and clustered disaster events on the coast. <p>Extreme storm events at a given site can be described using multivariate summary statistics, including the events maximum significant wave height (Hsig), median wave period, median wave direction, duration, peak storm surge, and time of occurrence. This requires a definition of individual storm events, and so the current methodology firstly involves the extraction of independent storm events from a 30-year timeseries of observations. Events are initially defined using a peaks-over-threshold approach based on the significant wave height. The value of 95% exceedance quantiles (2.93 m) is adopted. Subsequently, these events are manually checked against sea-level pressure data to examine if closely spaced events are generated by the same meteorological system, and if so the events are combined. This means that the final event set is more likely to consist of statistically independent storm events. <p>Various statistical techniques are applied to model the magnitude and frequency of the extracted storm events. A number of variations on the non-homogenous Poisson process model are developed to estimate the event occurrence rate, duration and spacing. The models account for the sub-annual variations in the occurrence rate, temporal dependency between successive events, and the finite duration of events. The results indicate that in the current dataset, closely spaced events are more temporally spread out than would be expected if the event timings were independent, which we term anti-clustering. A particular marginal distribution is fitted to each variable, i.e. a Generalised Pareto (GP) distribution for Hsig, and Pearson type 3 (PE3) distributions for duration and tidal residual. Empirical marginal distributions are employed for wave period and direction. The joint cumulative distribution function of all storm magnitude statistics is modelled by constructing dependency structure using Copula functions. Two methods are tested: a t-copula and a combination of a Gumbel and Gaussian copulas. Comparison of modelled and observed scatterplots shows similar pattern, and the difference of using the two methods is marginal. The goodness-of-fit tests such as Komologorov-Smirnov (K-S) tests, Chi-square tests and AIC and BIC are used to quantitatively evaluate the fitting qualities and to assess model parsimony, along with graphical visualisations e.g. QQ plots. <p>Based on this approach, a set of long-term synthetic time-series of storm events (106) is generated using the event magnitude and timing suggested by the optimised models. These long-term synthetic events can be used to derive exceedance probabilities and to construct designed storm events to be applied to the beach erosion modelling.

  • The Stavely Project is a collaboration between Geoscience Australia and the Geological Survey of Victoria. During 2014 fourteen pre-competitive stratigraphic drill holes were completed in the prospective Stavely region in western Victoria in order to better understand subsurface geology and its potential for a variety of mineral systems. The Stavely region hosts several belts of poorly-exposed Cambrian volcanic and intrusive rocks, visible largely only in aeromagnetic data, which have similarities to those found in modern subduction-related tectonic settings. Mineralisation associated with porphyry Cu-Au and volcanic-hosted massive sulphide mineral systems is known where these rocks are exposed around Mount Stavely and the Black Range. However, despite a history of mineral exploration dating back to the late 1960s, significant economic deposits are yet to be discovered, and the Stavely region remains a greenfields terrane. Given the geological setting and known mineral potential, opportunity exists for the discovery of large mineral systems beneath extensive, but relatively thin, younger cover. The Stavely Project aims to provide the framework for discovery in the Stavely region primarily through the acquisition and delivery of pre-competitive geoscientific data. This includes the completion of pre-competitive stratigraphic drill holes in order to test regional geological interpretations and recover material for detailed lithological, petrophysical, geochemical and geochronological analysis. The results will assist in understanding the mineral systems potential of the Stavely region under cover. This report describes the logging methods and procedures used to produce lithology logs for stratigraphic drill holes completed as part of the Stavely Project. Data presented in this release include summary and detailed geological logs, logging metadata, and graphic geological logs. Also included are reports on biostratigraphic and palynological age constraints of unconsolidated drill core, and on volcanic facies observed in the volcanic rocks intersected during drilling.

  • The Stavely Project is a collaboration between Geoscience Australia and the Geological Survey of Victoria. During 2014 fourteen pre-competitive stratigraphic drill holes were completed in the prospective Stavely region in western Victoria in order to better understand subsurface geology and its potential for a variety of mineral systems. The Stavely region hosts several belts of poorly-exposed Cambrian volcanic and intrusive rocks, visible largely only in magnetic data, which have similarities to those found in modern subduction-related tectonic settings. Mineralisation associated with porphyry Cu-Au and volcanic-hosted massive sulphide mineral systems is known where these rocks are exposed around Mount Stavely and the Black Range. However, despite a history of mineral exploration dating back to the late 1960s, significant economic deposits are yet to be discovered, and the Stavely region remains a greenfields terrane. Given the geological setting and known mineral potential, opportunity exists for the discovery of large mineral systems beneath extensive, but relatively thin, younger cover. The Stavely Project aims to provide the framework for discovery in the Stavely region primarily through the acquisition and delivery of pre-competitive geoscientific data. This includes the completion of pre-competitive stratigraphic drill holes in order to test regional geological interpretations and recover material for detailed lithological, petrophysical, geochemical and geochronological analysis. The results will assist in understanding the mineral systems potential of the Stavely region under cover. This report summarises data collected in the field at the drill sites, either during or immediately following drilling, as part of the Stavely Project, and describes the methods and procedures used. Data presented in this release include drill hole collar information, operational metadata and daily drilling reports, drill core photographs, down-hole surveys, down-hole wireline geophysical logging results, down-hole temperature logging results, down-hole AutoSondeTM gamma data, Lab-at-RigTM X-ray fluorescence data, diamond drill core recovery percentages, and handheld magnetic susceptibility measurements on the drill core.

  • A short film describing the development of a prototype application for the Oculus Rift DK2 headset, to visualise subsurface geoscience data in situ. Synopsis: Visualisation and Science Promotion team members Michael de Hoog and Bobby Cerini visited Lake George in southern New South Wales, to demonstrate how the Oculus Rift is used to integrate subsurface resources data in situ with views of the landscape. In the opening sequence, Michael and Bobby set off across the dry lake bed. Michael is wearing the Oculus Rift headset while Bobby carries a laptop, containing georeferenced data previously gathered by Geoscience Australia. The headset has a camera attached to capture the view and enable tracking of Michael's head movements. The video shows what Michael is seeing as he looks around. Different data layers are shown being switched on and off, as Michael gazes at different parts of the landscape. The data are overlaid on the precise location within the landscape in which they were collected, including seismic line, volumes, gravity, magnetic and borehole data. The view changes to show Michael at the lakeside, wearing the Oculus Rift headset and looking at the wider landscape. Again the subsurface data is shown. The geographical extent of the data gathered in this area is revealed with Michael's head movements. A voiceover accompanying the movie describes the processes used to make the film and to show what the headset wearer sees. Script: Bobby Cerini, Michael de Hoog Data visualisation, application development: Michael de Hoog Cinematography, editing, audio: Michael O'Rourke Titles: Kath Hagan

  • Video of the geo-heritage aspects of the rocks of Stornes Peninsula, Larsemann Hills

  • A series of short video clips describing how data positions us for the future, consisting of the following titles: How data positions us for the future: Bush fire response A short video showing how the national positioning infrastructure managed by Geoscience Australia underpins the work of hazard management professionals. How data positions us for the future: Precision agriculture A short video showing how the national positioning infrastructure managed by Geoscience Australia underpins the work of the agricultural industry. How data positions us for the future: Urban navigation A short video showing how the national positioning infrastructure managed by Geoscience Australia underpins the everyday life of Australians. Detailed production information: Concept development: Catherine Edwardson, Bobby Cerini, Julie Silec, Michael O'Rourke, Neil Caldwell, Simon. Costello, John Dawson Production management: Bobby Cerini, Julie Silec Video production: Julie Silec, Michael O'Rourke, Neil Caldwell Videography: Bobby Cerini; Rural Fires Service NSW; stock imagery also used