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  • This service represents the National Digital Elevation Model (DEM) 1 Second Percentage Slope product, derived from the National DEM SRTM 1 Second. Slope measures the inclination of the land surface from the horizontal. Percent slope represents this inclination as the ratio of change in height to distance.

  • The Pixel Quality (PQ) product is an assessment of whether an image pixel represents an un-obscured, unsaturated observation of the Earth's surface and whether the pixel is represented in each spectral band. The PQ product allows users to produce masks which can be used to exclude pixels which don't meet various quality criteria from further analysis. The capacity to automatically exclude such pixels from analysis is essential for emerging multi-temporal analysis techniques that make use of every quality assured pixel within a time series of observations. The PQ count (PQ-COUNT) product is a count of how many times a pixel contains a clear observation of the earth's surface (land or sea) at a particular location for a particular period of time. PQ-COUNT is available for the following epochs: PQ-COUNT-SUMMARY, this contains a count of all observations contained within the DEA (from 1987 to the most up to date imagery available); PQ-COUNT-ANNUAL-SUMMARY, this contains a count of the number of observations acquired in each full calendar year (1st of January - 31st December) from 1987 to the most recent full calendar year; PQ-COUNT-SEASONAL-SUMMARY, this contains a count of the number of observations acquired within each calendar season (DJF, MAM, JJA, SON). This product is available for the most recent 8 seasons.

  • This study compares cover thickness estimates from geophysical techniques acquired prior to drilling to preliminary results from the Coompana Drilling Program in the far west of South Australia. Prior to drilling, geophysical techniques consisting of magnetotellurics (MT) and reflection and refraction seismic were deployed to estimate the thickness of Cenozoic cover sediments at the proposed drill-sites. The estimates of cover thickness assisted with planning the Coompana Drilling Program and helped to de-risk the stratigraphic drilling by providing estimates of cover thickness.

  • Since soon after the federation of Australia in 1901 Geoscience Australia, and its predecessors organisations, have gathered a significant collection of microscope slide based items (including: thin sections of rock, micro and nano fossils) from across Australia, Antarctica, Papua New Guinea and beyond. The samples from which the microscope slides were produced have been gathered via extensive geological mapping programs, work conducted for major Commonwealth building initiatives such as the Snowy Mountain Scheme and science expeditions. The cost of recreating this collection, if at all possible, would be measured in the $100Ms (AUS) even assuming that it was still possible to source the relevant samples. Access to these slides is open to all but it has not been easy to locate specific slides due to the largely ledger and card catalogue management system. The fragmented nature of the management system with the increasing potential for the deterioration of physical media and the loss of access to even some of the original contributors meant that rescue work was (and still is) needed urgently. Through the use of citizen science the project has seen the transcription of some 35,000 sample metadata and data records from a variety of hardcopy sources by a diverse group of volunteers. The availability of these data has allowed for the electronic discovery of both the microscope slides and their parent samples, and will hopefully lead to a greater utilisation of this valuable resource and enable new geoscientific insights from old resources.

  • Australia is about to become the premier global exporter of liquefied natural gas (LNG), bringing increased opportunities for helium extraction. Processing of natural gas to LNG necessitates the exclusion and disposal of nonhydrocarbon components, principally carbon dioxide and nitrogen. Minor to trace hydrogen, helium and higher noble gases in the LNG feed-in gas become concentrated with nitrogen in the non-condensable LNG tail gas. Helium is commercially extracted worldwide from this LNG tail gas. Australia has one helium plant in Darwin where gas (containing 0.1% He) from the Bayu-Undan accumulation in the Bonaparte Basin is processed for LNG and the tail gas, enriched in helium (3%), is the feedstock for helium extraction. With current and proposed LNG facilities across Australia, it is timely to determine whether the development of other accumulations offers similar potential. Geoscience Australia has obtained helium contents in ~800 Australian natural gases covering all hydrocarbon-producing sedimentary basins. Additionally, the origin of helium has been investigated using the integration of helium, neon and argon isotopes, as well as the stable carbon (13C/12C) isotopes of carbon dioxide and hydrocarbon gases and isotopes (15N/14N) of nitrogen. With no apparent loss of helium and nitrogen throughout the LNG industrial process, together with the estimated remaining resources of gas accumulations, a helium volumetric seriatim results in the Greater Sunrise (Bonaparte Basin) > Ichthys (Browse Basin) > Goodwyn–North Rankin (Northern Carnarvon Basin) accumulations having considerably more untapped economic value in helium extraction than the commercial Bayu-Undan LNG development.

  • Tsunamis are relatively rare in Australia and emergency managers rely on the sharing of information at national forums to assist them to manage the tsunami risk in their own jurisdiction. Emergency managers responsible for tsunami risk management across Australia recently identified the need for national consistency in tsunami hazard information and as a result, a project was initiated to develop national guidelines for tsunami hazard modelling. This presentation will outline the approach adopted to develop these guidelines, focusing on the collaboration of end-users and tsunami modelling practitioners. The guidelines were explicitly designed to facilitate appropriate standards of rigour and improved national consistency in tsunami hazard modelling, without dictating software choices or otherwise suppressing innovative practices (which will evolve over time in concert with improvements in tsunami science). The guidelines focused instead on providing guidance in designing a study suitable for the use-case being considered. Core issues included the treatment of uncertainties in tsunami generation, propagation and inundation modelling, and scenario return periods. Whilst the emergency managers proposed the development of these guidelines, the target audience included any agency would could commission tsunami hazard studies for a particular purpose (e.g. coastal infrastructure owners, insurance), as well as the tsunami modellers conducting such studies. The guidelines will also become a valuable resource for the tsunami modelling community. In many situations, tsunami modelling is conducted by coastal hazard modellers who may not have current understanding of Australia’s tsunami hazard.

  • Poster that shows Australian earthquakes greater than a magnitude 4.5 between 1964 and 2017

  • The Australian Resource Reviews are periodic national assessments of individual mineral commodities. The reviews include evaluations of short-term and long-term trends for each mineral resource, world rankings, production data, significant exploration results and an overview of mining industry developments.

  • <p>This dataset measures the mean decadal warming rates of the sea surface temperature (SST) in 58 Australian Marine Parks (with the exception of the Heard Island and McDonald Islands Marine Park) over the past 25 years (1992 to 2016). They are derived from the Sea Surface Temperature Atlas of the Australian Regional Seas (SSTAARS). The field of “trend_d” represents the linear SST trend for March 1992 to December 2016. The unit of the warming rates is Celsius degree/per decade. <p>This research is supported by the National Environmental Science Program (NESP) Marine Biodiversity Hub through Project D1.

  • <p>The dataset indicates the long-term overall primary productivity hotspots of ocean surface waters. They are derived from MODIS (aqua) images using NASA's SeaDAS image processing software. The monthly chlorophyll a images between July 2002 and August 2014 are used to identify the overall primary productivity hotspots. The extent of the dataset covers the entire Australian EEZ and surrounding waters (including the southern ocean). The value (between 0 and 1.0) of the dataset represents the likelihood of the location being a primary productivity hotspot. <p>This research is supported by the National Environmental Science Program (NESP) Marine Biodiversity Hub through Project D1.