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  • The Joint Australian Tsunami Warning Centre (JATWC) provides 24/7 monitoring of earthquake and tsunami hazards affecting Australia and the Indian Ocean. The JATWC comprises Geoscience Australia, who undertake earthquake monitoring in Canberra, and the Bureau of Meteorology in Melbourne, who issue tsunami bulletins and monitor the sea level. Earthquakes are monitored at Geoscience Australia in real-time via a total network of over 260 seismic stations from both the Australian National Seismic Network (ANSN); and a collection of global stations, collaborating with other earthquake monitoring groups and organisations locally and internationally. This enables the quick detection and response to local, regional and global earthquakes, and assessment of its potential to generate a tsunami. If an earthquake is deemed to be tsunamigenic, earthquake information is used by the JATWC to deliver a tsunami warning based on the magnitude, depth and location of the earthquake combined with tsunami models. These warnings are supplemented with sea level information to validate the tsunami warning. Geoscience Australia also provides earthquake information and advice about Australian earthquakes and large international earthquakes to the Australian Government and general public. This is valuable for building safer communities in a world where the impacts of natural disasters can be far-reaching.

  • The National Geochemical Survey of Australia (NGSA; www.gov.au/ngsa) collected and analysed catchment outlet sediments at 1315 sites over most of Australia (Caritat & Cooper, 2011). Multivariate statistical assessment of the NGSA data revealed significant regional-scale geological features that were supported by independent proximal and remotely sensed geoscientific datasets (Caritat & Grunsky, 2013). The aim of this study was to test, using the NGSA data, whether treating the data according to rigorous Compositional Data (CoDa) principles improved the outcomes of prospectivity analysis for mineral exploration or not.

  • The Oceanic Shoals Commonwealth Marine Reserve (CMR) (>71,000 km2) is located in the Timor Sea and is part of the National Representative System of Marine Protected Areas of Australia. The Reserve incorporates extensive areas of carbonate banks and terraces that are recognised in the North and North West Marine Region Plans as Key Ecological Features (KEFs). Although poorly studied, these banks and terraces have been identified as potential biodiversity hotspots for the Australian tropical north. As part of the National Environment Research Program Marine Biodiversity Hub, Geoscience Australia in collaboration with the Australian Institute of Marine Science undertook a marine biodiversity survey in 2012 to improve the knowledge of this area and better understand the importance of these KEFs. Amongst the many activities undertaken, continuous high-resolution multibeam mapping, video and still camera observations, and physical seabed sampling of four areas covering 510 km2 within the western side of the CMR was completed. Multibeam imagery reveals a high geomorphic diversity in the Oceanic Shoals CMR, with numerous banks and terraces, elevated 30 to 65 m above the generally flat seabed (~105 m water depth), that provide hard substrate for benthic communities. The surrounding plains are characterised by fields of depressions up to 1 m deep (pockmarks) formed in soft silty sediments that are generally barren of any epibenthos (Fig .1). A distinctive feature of many pockmarks is a linear scour mark that extends several tens of metres (up to 150 m) from pockmark depressions. Previous numerical and flume tank simulations have shown that scouring of pockmarks occurs in the direction of the dominant near-seabed flow. These geomorphic features may therefore serve as a proxy for local-scale bottom currents, which may in turn inform on sediment processes operating in these areas and contribute to the understanding of the distribution of biodiversity. This study focused on characterising these seabed scoured depressions and investigating their potential as an environmental proxy for habitat studies. We used ArcGIS spatial analyst tools to quantify the features and explored their potential relationships with other variables (multibeam backscatter, regional modelled bottom stress, biological abundance and presence/absence) to provide insight into their development, and contribute to a better understanding of the environment surrounding carbonate banks. Preliminary results show a relationship between pockmark types, (i.e. with or without scour mark) and backscatter strength. This relationship suggests some additional shallow sub-surface control, mainly related to the presence of buried carbonate banks. In addition, the results suggest that tidal flows are redirected by the banks, leading to locally varied flow directions and 'shadowing' in the lee of the larger banks. This in turn is likely to have an influence on the observed density and abundance of benthic assemblages.

  • In July 2010, Geoscience Australia and CSIRO Marine & Atmospheric Research jointly commissioned a new atmospheric composition monitoring station, named Arcturus, in sub-tropical Queensland, Australia. The facility is designed as a proto-type remotely operated `baseline monitoring station' that could be deployed in areas that are likely targets for commercial scale geological storage of carbon dioxide. A key question, given the ecosystem and anthropogenic sources of CO2 in the region, and the absence of a 'clean-wind' sector baseline, is how large would a CO2 leak have to be from a geological storage site before it can be detected above the background CO2 signal? To address this, CO2 leak simulation modelling was performed for 1-year period using the coupled prognostic meteorological and air pollution model TAPM at various locations, emission rates and distances (1-10 km) from the station.

  • Poster prepared for International Association of Hydrogeologists Congress 2013 Surface-groundwater interactions are often poorly understood. This is particularly true of many floodplain landscapes in Australia, where there is limited mapping of recharge and discharge zones along the major river systems, and only generalised quantification of hydrological fluxes based on widely spaced surface gauging stations. This is compounded by a lack of temporal data, with poor understanding of how surface-groundwater interactions change under different rainfall, river flow and flood regimes. In this study, high resolution LiDAR, in-river sonar, and airborne electromagnetic (AEM) datasets (validated by drilling) have been integrated to produce detailed 3-dimensional mapping that combines surface geomorphology and hydrogeology. This mapping enables potential recharge zones in the river and adjacent landscape to be identified and assessed under different flow regimes. These potential recharge zones and groundwater flow pathways were then compared against the spatial distribution of discontinuities in near-surface and deeper aquitard layers derived from the AEM interpretation. These 3D mapping constructs provide a framework for considering groundwater processes. Hydrochemistry data, allied with hydraulic data from a bore monitoring network, demonstrate the importance of recharge during significant flood events. In many places, the AEM data also affirm the spatial association between fresher groundwater resources and sites of river and floodplain leakage. At a more localised scale, hydrogeochemical data allows discrimination of lateral and vertical fluxes. Overall, this integrated approach provides an important conceptual framework to constrain hydrogeological modelling, and assessments of sustainable yield. The constructs are also invaluable in targeting and assessing managed aquifer recharge (MAR) options.

  • Poster prepared for International Association of Hydrogeologists Congress 2013 In this study, a multi-disciplinary systems mapping approach has completely revised our understanding of the age, stratigraphy, mode of deposition and landscape evolution of Lower Darling Valley (LDV) sediments within the north-western Murray Basin. The Cenozoic sequence in this area contains Paleogene and Neogene shallow marine, fluvial and shoreline sediments overlain by Quaternary lacustrine, aeolian and fluvial units. The surficial Quaternary fluvial units of the valley form a complex group of morphostratigraphic units which vary in their distribution, character and geomorphic expression through the study area. Resolving the distribution of these units has been particularly important for understanding surface-groundwater interactions. In the LDV Quaternary fluvial sequence, multiple scroll-plain tracts are incised into higher, older more featureless floodplains. Prior to this study, these were respectively correlated to the Coonambidgal and Shepparton Formations of the Riverine Plain in the eastern Murray Basin and associated with the subsequently discarded Prior Stream/Ancestral River chronosequence of different climatically controlled depositional styles. In contrast to that proposition, we ascribe all LDV Quaternary fluvial deposition to lateral-migration depositional phases of one style, though with more variable stream discharges and channel and meander-scroll dimensions. Successively higher overbank-mud deposition through time obscures scroll traces and provides the main ongoing morphologic difference. A new morphostratigraphic unit, the Menindee Formation, refers to the mostly older and higher floodplain sediments, where scroll traces are obscured by overbank mud which continues to be deposited by the highest modern floods. Younger inset scroll-plain tracts, with visible scroll-plain traces, are still referred to the Coonambidgal Formation. Another new stratigraphic unit, the Willotia beds, refers to even older fluvial sediments, now above modern floodplain levels and mostly covered by aeolian sediments. This work provides important insights into the nature of Australian Quaternary fluvial deposition, with important implications for hydrogeological processes, groundwater resources and the assessment of managed aquifer recharge options.

  • Back wall poster display in the library celebrating Library and Information Week 2014

  • Geoscience Australia has committed to an integrated program of data stewardship with the inception of the Geoinformatics and Data Services Section (GDSS) in 2013, whose mission is to maximise the online discovery, access, sharing, interoperability and use of Geoscience Australia's science data. The section comprises small teams of specialists whose skills cross the realm of geoscience, computer science, spatial science, policy, information management and IT. These teams research, strategise, plan, coordinate, advise, innovate, implement and manage enterprise data, systems, tools and services with a unique awareness of the interdependencies between IT, science, culture and governance. GDSS collaborates with researchers and experts to ensure the projects, standards, models and tools we implement are international best practice. This poster highlights some of the initiatives we are progressing.