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  • A postcard providing an overview of the marine ecology programme at Geoscience Australia

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

  • 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.

  • Unique challenges are faced in modelling faults in intraplate regions for seismic hazard purposes. Low fault slip rates compared to landscape modification rates lead to often poor discoverability of fault sources, and favours incomplete characterisation of rupture behaviours. Irrespective, regional and local test cases have demonstrated that fault sources assigned activity rates consistent with paleoseismic observations have the potential to significantly impact probabilistic seismic hazard assessments in Australia. To reflect this, the 2018 Australian NSHA will for the first time incorporate a fault source model. The model includes over 300 onshore faults, and a handful of offshore faults, which are modelled as simplified planes and assigned a general dip and dip direction. Dips are obtained from seismic-reflection profiles, where available, or inferred by taking into account surface geology and geomorphology, or other fault geometries within similar neotectonic settings. The base of faulting is generally taken as the regional maximum depth of distributed seismicity. Slip rates are calculated from displaced strata of known age, estimated from surface expression, or are extrapolated from other faults within similar neotectonic settings. We construct logic trees to capture epistemic uncertainty in fault source parameters, including magnitude frequency distribution, and the potential for random, periodic or episodic recurrence behaviour. This presentation introduces the new fault source database, the fault source logic tree as it currently exists, and discusses uncertainty in and sensitivity to various elements of the proposed fault source input model.

  • A compilation video of flythrough footage showing Great Barrier Reef bathymetry visualisations. Primarily for use by media.

  • <p>Flythrough movie of Bremer Commonwealth Marine Reserve, southwest Western Australia showing bathymetry of Bremer Canyon, Hood Canyon, Henry Canyon and Knob canyon. <p>This research is supported by the National Environmental Science Program (NESP) Marine Biodiversity Hub through Project D1.

  • The 2018 revision of Australia's National Seismic Hazard Assessment (NSHA18) represents a substantial improvement from the 2013 NSHA. In particular, this revision will include a fault source models, an improved and more homogeneous earthquake catalogue, and greater epistemic uncertainty through a call for third party source models. This paper presents updated models of seismicity and ground motion that are currently being developed at Geoscience Australia for the NSHA. We use the OpenQuake software to calculate seismic hazard for Australia and compare with OpenQuake implementations of third-party models and the 2013 NSHA. Weighting of logic tree branches for alternative models are discussed, and how these relate to the fundamental datasets on which they are based. A smoothed seismicity model is developed based on recent seismicity while source models derived from neotectonic fault data consider a much longer time history. Final weightings, including for third party models, will be determined in consultation with members of the Australian seismological community.

  • 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)

  • <p>Bathymetry flythrough of Perth Canyon using data acquired by Schmidt Ocean Institute in 2015 on RV Falkor (University of Western Australia et al.). The flythrough highlights geomorphic features mapped by Geoscience Australia, including landslides, escarpments and bedform fields and biodiversity associated with the canyon (benthic and pelagic). Produced as a science communication product for the Marine Biodiversity Hub (National Environmental Science Program). <p>This research is supported by the National Environmental Science Program (NESP) Marine Biodiversity Hub through Project D1.