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  • This service provides Australian surface hydrology, including natural and man-made features such as water courses (including directional flow paths), lakes, dams and other water bodies. The information was derived from the Surface Hydrology database, with a nominal scale of 1:250,000. The National Basins and Catchments are a national topographic representation of drainage areas across the landscape. Each basin is made up of a number of catchments depending on the features of the landscape. This service shows the relationship between catchments and basins. The service contains layer scale dependencies.

  • This service includes world bathymetry, elevation (hillshade), and satellite imagery data, and ocean, country, population and natural features. The information was derived from various sources, including Natural Earth and Landsat Imagery. It is a cached service with a Web Mercator Projection. The service contains layer scale dependencies.

  • 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.

  • Magnetotelluric (MT) measures the natural variations of the Earth's magnetic and electrical (telluric) fields. The Audio-Magnetotelluric method (AMT) samples signals in the frequency range of 10k Hz down to ~1Hz and provides information to the upper few kilometres of the crust. AMT data were collected at ten sites in the southern Thomson Orogen using Phoenix Geophysics equipment (MTU-5A, MTC-150L and PE5 electrodes). Instrument deployment periods were 7/Oct -29/Oct 2015 and 03/Aug-10/Aug 2016. Time series data were processed into frequency domain using remote reference and Robust Processing scheme. After quality assurance, processed data were exported to industry-standard EDI files. Time series data are available on request.

  • Seismic data, calibration and State of Health files. 2005-2007

  • The product consists of 8,800 line kilometres of time‐domain airborne electromagnetic (AEM) geophysical data acquired over the far north part of South Australia known as the Musgrave Province. This product release includes: a) the measured AEM point located data, b) electrical conductivity depth images derived from the dataset, and c) the acquisition and processing report. The data were acquired using the airborne SkyTEM312 Dual Moment 275Hz/25Hz electromagnetic and magnetic system, which covered a survey area of ~14,000 km2, which includes the standard 1:250 000 map sheets of SG52-12 (Woodroffe), SG52-16 (Lindsay), SG53-09 (Alberga) and SG53-13 (Everard). The survey lines where oriented N-S and flown at 2km, 500m and 250m line spacing. A locality diagram for the survey is shown in Figure 1. This survey was funded by the Government of South Australia, as part of the Plan for Accelerating Exploration (PACE) Copper Initiative, through the Department of the Premier and Cabinet, (DPC) and the Goyder Institute of Water Research. Geoscience Australia managed the survey as part of a National Collaborative Framework project agreement with SA. The principal objective of this project was to capture a baseline geoscientific dataset to provide further information on the geological context and setting of the area for mineral systems as well as potential for groundwater resources, of the central part of the South Australian Musgrave Province. Geoscience Australia contracted SkyTEM (Australia) Pty. Ltd. to acquire SkyTEM312 electromagnetic data, between September and October 2016. The data were processed and inverted by SkyTEM using the AarhusInv inversion program (Auken et al., 2015) and the Aarhus Workbench Laterally Constrained Inversion (LCI) algorithm (Auken et al. 2005; Auken et al. 2002). The LCI code was run in multi-layer, smooth-model mode. In this mode the layer thicknesses are kept fixed and the data are inverted only for the resistivity of each layer. For this survey a 30 layer model was used. The thickness of the topmost layer was set to 2 m and the depth to the top of the bottommost (half-space) layer was set to 600 m. The layer thicknesses increase logarithmically with depth. The thicknesses and depths to the top of each layer are given in Table 1. The regional AEM survey data can be used to inform the distribution of cover sequences, and at a reconnaissance scale, trends in regolith thickness and variability, variations in bedrock conductivity, and conductivity values of key bedrock (lithology related) conductive units under cover. The data will also assist in assessing groundwater resource potential and the extent of palaeovalley systems known to exist in the Musgrave Province. A considerable area of the survey data has a small amplitude response due to resistive ground. It very soon becomes evident that lack of signal translates to erratic non-monotonic decays, quite opposite to the smooth transitional exponential decays that occur in conductive ground. Some sections of the data have been flown over what appears to be chargeable ground, hence contain what potentially can be identified as an Induced Polarization effect (airborne IP—AIP). For decades these decay sign changes, which characterize AIP, have not been accounted for in conventional AEM data processing and modelling (Viezzoli et al., 2017). Instead they have mostly been regarded as noise, calibration or levelling issues and are dealt with by smoothing, culling or applying DC shifts to the data. Not accounting for these effects is notable on the contractor’s conductivity-depth sections, where data can’t be modelled to fit the data hence large areas of blank-space have been used to substitute the conductivity structure. The selection of the survey area was undertaken through a consultative process involving the CSIRO, GOYDER Institute, Geological Survey of South Australia and the exploration companies currently active in the region (including industry survey partner PepinNini Minerals Ltd). The data will be available from Geoscience Australia’s web site free of charge. It will also be available through the South Australian Government’s SARIG website at https://map.sarig.sa.gov.au. The data will feed into the precompetitive exploration workflow developed and executed by the Geological Survey of South Australia (GSSA) and inform a new suite of value-added products directed at the exploration community.

  • From the beginning of petroleum exploration in the Perth Basin, the importance of the Early Triassic marine Kockatea Shale was recognised as the principal source for liquid petroleum in the onshore northern Perth Basin (Powell and McKirdy, 1976). Thomas and Barber (2004) constrained the effective source rock to a Early Triassic, middle Sapropelic Interval in the Hovea Member of the lower Kockatea Shale. In addition, Jurassic and Permian sourced-oils (Summons et al., 1995) demonstrate local effective non-Kockatea source rocks. However, evidence for multiple effective gas source rocks is limited. This study utilizes the molecular composition and carbon and hydrogen isotopic compositions of 34 natural gases from the Perth Basin, extending the previous study (Boreham et al., 2001) to the offshore and includes hydrogen isotopes and gases. It shows the existence of Jurassic to Permain gas systems in the Perth Basin.

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    Gravity data measures small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This Cape York Gravity Survey, Qld, 2009 (P200940), Bouguer 1VD grid is a first vertical derivative of the Bouguer anomaly grid for the Cape York Gravity Survey, Qld, 2009 (P200940) survey. This gravity survey was acquired under the project No. 200940 for the geological survey of QLD. The grid has a cell size of 0.0075 degrees (approximately 820m). A total of 9244 gravity stations were acquired to produce the original grid. A Fast Fourier Transform (FFT) process was applied to the original grid to calculate the first vertical derivative grid.

  • The Browse Basin is located offshore on Australia's North West Shelf and is a proven hydrocarbon province hosting gas with associated condensate; however, oil reserves are small. The assessment of a basin's oil potential traditionally focusses on either the presence or absence of oil-prone source rocks. However, light oil can be found in basins where the primary hydrocarbon type is gas-condensate and oil rims form whenever these fluids migrate into reservoirs at pressures below their dew point (or saturation pressure). The relationship between dew point pressure and condensate-gas ratio (CGR) depends on the liquid composition and is therefore a petroleum system characteristic (Fig. 1). By combining geochemical studies of source rocks and fluids with petroleum systems analysis, the four Mesozoic petroleum systems identified by their geochemical fingerprints (Rollet et al., 2016) can be correlated with several gas-prone (dew point) petroleum systems: 1. Gas-condensates generated and reservoired within the Lower-Middle Jurassic Plover Formation are derived from terrestrial organic matter in fluvio-deltaic to pro-deltaic environments. Such gas is dominated by methane (gas dryness* = 91%), with ideal gas condensate ratios (CGRs) ranging between 7 and 35 bbl/MMscf. Liquids recovered from wells tested along the Scott Reef Trend (e.g. Calliance, Brecknock and Torosa) comprise pale yellow condensates (49-53° API gravity), as do those from the deepest (Plover) reservoirs within the Ichthys gas accumulation (e.g. Gorgonichthys). These liquids plot on Figure 1 as dew point fluids. The molecular and carbon isotopic signatures of these condensates are similar, classifiying them into a single family (W1_1BRO) in Figure 2. The biomarkers providing the strongest discrimination are the high relative abundances of C29 sterane and C19 tricyclic triterpane, coupled with an enrichment in delta13C of their saturated and aromatic hydrocarbon fractions testifies to their terrestrial organic origin. 2. Fluids with similar bulk properties (gas dryness = 91%; ideal CGRs 27-52 bbl/MMscf) to those of the aformentioned Plover-sourced fluids are found in the greater Crux accumulation in the Heywood Graben. The pale yellow condensates (47°API gravity) also exhibit similar biomarker assemblages as the W1_1BRO family. However, due to their greater enrichment in delta13C, the condensates plot as a separate family (W1_2BRO) in Figure 2. A difference in thermal maturity is also noted, with the Crux accumulation having lower maturity (calculated vitrinite reflectance# [Rc] = 0.77%) relative to the condensates on the Scott Reef Trend (av Rc = 1.18%). The most likely source rocks for the Crux fluids are the terrestrially-dominated Plover Formation coals and shales, but shaly coals also occur within the thick Upper Jurassic section in the northern part of the basin. These fluids are categorised as a separate dew point system within the Heywood Graben (Fig. 1). 3. Gas-condensates reservoired within the Brewster Member of the upper Vulcan Formation in the Ichthys/Prelude and Burnside accumulations have a greater liquid content than the aformentioned gases, with ideal CGRs of 22-151 bbl/MMscf at Titanichthys 1 and a gas dryness of 84%. The pale yellow condensates have API gravities of 55° and are potentially a separate intraformational dew point petroleum system within the central Caswell Sub-basin. Their biomarker and isotopic signatures indicate derivation from mixed marine and land-plant organic matter and plot as another family (W2W3_1BRO; Fig. 2). The source of these fluids is probably the organic-rich shales of the Upper Jurassic-Lower Cretaceous Vulcan Formation that encase the Brewster Member sandstone reservoir. PVT data for Brewster-reservoired fluids is affected by synthetic mud contamination, which has an impact on the measured dew point pressures. In the absence of measured values, a similar phase behaviour to North Sea (UK) gas-condensates (England, 2002) is assumed. 4. The Cretaceous reservoir in Caswell contains an unbiodegraded brown 'light oil' (47°API gravity) but PVT data are not available. Biomarker and isotope signatures show that the liquids were generated from source rocks containing both marine and terrigenous organic matter lying within the early oil window (Rc# = 0.75%). They correlate with the Yampi Shelf biodegraded oils (W3_1BRO, Fig. 2), gas at Adele, and with extracts of the Lower Cretaceous Echuca Shoals Formation (Boreham et al., 1997). However, these marine shales have low hydrogen indices (~200 mg hydrocarbons/gTOC) and hence may only be able to expel sufficient hydrocarbons to sustain migration over short distances. Since biodegraded solution gases in the Yampi Shelf accumulations contain neo-pentane - a highly resistant compound - with isotopic affinity to Plover Formation generated fluids, it is possible that Cretaceous-sourced liquids were mobilised and carried to the shelf edge by co-migrating Plover-derived gas.

  • This poster shows earthquakes occurring in Australia in 2016 with a background of earthquake activity in Australia over the past 10 years. Also included are images produced as part of the analysis of the Petermann Ranges Earthquakes -, the offshore Bowen Earthquakes -, and the Norsemann Earthquakes Sequences. A yearly summary of earthquake occurrences in Australia as well as the top 10 Australian earthquakes in 2016 are presented.