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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.

  • Geoscience Australia Flight Line Diagrams Catalogue Archive

  • The data covers an area of approximately 8500 sq km in the Darling river catchment area, located between Bourke, NSW and Wilcannia, NSW. A set of seamless products were produced including hydro-flattened bare earth DEMs, DSMs, Canopy Height Models (CHM) and Foliage Cover Models (FCM). The outputs of the project are compliant with National ICSM LiDAR Product Specifications and the NEDF.

  • Large tsunami occur infrequently but can be extremely destructive to human life and the built environment. Management of these risks requires an understanding of the possible sizes of future tsunami, and the probability that they will occur over some time interval of interest. Herein we present a globally extensive probabilistic assessment of tsunami runup hazards, considering only earthquake sources as these have been responsible for about 80% of destructive tsunami globally. The global scale of the analysis prevents us from exploiting detailed site specific data (e.g. high-resolution elevation data, tsunami observations), and because of this we do not suggest the analysis is appropriate for local decision making. However, consistent global analyses are useful to inform international disaster risk reduction initiatives, and can also serve as a reference and potential source of boundary conditions for regional and local tsunami hazard assessments. A global synthetic catalogue of 17000 tsunamigenic earthquake events is developed with magnitudes ranging from 7.5 to 9.6. The geometry of the earthquake sources accounts for the detailed three-dimensional shape of subduction interfaces, when the latter is well constrained. The rate of earthquake events is modelled such that on each earthquake source zone, the earthquakes follow a Gutenberg-Richter magnitude-frequency distribution, and the time-integrated earthquake slip balances the seismic moment release rate inferred from the convergence of neighbouring tectonic plates. Tsunami propagation from each earthquake is modelled globally, and runup height is estimated roughly by combining the global model with heuristic treatments of nearshore tsunami amplification. We evaluate the accuracy of this approach by comparing runup observations from four globally significant historical tsunami with model scenarios having the same earthquake magnitude and location (i.e. without event-specific calibration). Around 50% of runup observations are within a factor of two of the model predictions. The dominant source of uncertainty in the modelled runup seems related to limitations in the earthquake source representation, with limitations due to the global runup methodology being a significant but secondary issue. These uncertainties are modelled statistically, and integrated into the hazard computations. In most locations, the modelled tsunami runup exceedance rate is sensitive to assumptions about the maximum possible earthquake magnitude on nearby earthquake source zones, and the fraction of plate convergence accommodated by non-seismic processes. We model the uncertainties of these (typically) poorly constrained processes using a logic-tree. For any site and chosen exceedance rate, this allows the mean runup (integrated over all logic tree branches) to be estimated, and associated runup confidence intervals to be derived. As well as highlighting the uncertainties in tsunami hazard, the analysis suggests relatively high hazard around most of the Pacific Rim, especially on the east coast of Japan and the west coast of South America, and relatively low hazard around most of the Atlantic outside of the Caribbean. Runup hazards on the east and west coast of Australia are relatively poorly constrained, because there are large uncertainties in the maximum magnitude earthquake which could occur on key source zones in the eastern Indian Ocean and western Pacific.

  • Geoscience Australia conducted an absolute gravity survey during May and June 2016 in order to maintain and update the Australian Fundamental Gravity Network (AFGN). During the 2016 AFGN field campaign 21 absolute gravity readings were taken with an A10 gravity meter.

  • Polarity checks of South Australian Government Seismic Network, 2000. 36 stations.

  • This forum showcased the range of pre-competitive geoscience projects currently underway by Geoscience Australia and its collaborative partners under the UNCOVER themes with an emphasis on new projects arising out of the Australian Government’s four year $100M Exploring for the Future program which commenced in late 2016. The themes covered are: Cover and what lies beneath, character and thickness; 3D architecture, mapping the framework for mineral systems; 4D geodynamics and mineral systems of Australia; and, Mineral system footprints and toolkits for explorers

  • In the present, the GNSS body-fixed reference frame definition is followed according to the International GNSS Service (IGS) conventions [3] which are based on the spacecraft body frame of the GPS Block II/IIA satellites. This definition is also compatible with the GPS Block IIF satellites while in the case of the GPS Block IIR the spacecraft frame is designed with a reverse direction (away from the sun) in the X axis of the body-fixed frame. The situation is similar to the GPS IIA/IIF for the BDS satellites where +X axis points towards the Sun, +Z axis points to the SV’s radius vector towards the Earth’s centre in the antenna boresight direction, and the +Y axis completes the right handed system while it coincides with the rotation axis of the solar panels. The yaw angle is the critical parameter which defines the GNSS attitude. Contrary to GPS and GLONASS, BeiDou Inclined Geosynchronous Orbit (IGSO) and Mean Earth Orbit (MEO) satellites do not experience noon-turn and midnight-turn manoeuvres [6], with the exception of the newly launched IGSO6 or C13, formerly C15 (F. Dilssner and P. Steigenberger personal communication).

  • 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.