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  • Himawari-8, a geostationary satellite operated by the Japan Meteorological Agency, became operational in July 2015. The high frequency (10 min) and resolution (~2km) of Himawari-8 data provides an enormous opportunity for the monitoring and investigation of highly dynamic oceanographic phenomena. This presentation aims to demonstrate the value of himawari-8 SST data for studies of the Bonney Coast upwelling, East Australian Current (EAC) and Madden-Julian Oscillation (MJO) diurnal SST (dSST) variations. During the 2016–17 summer, we identified three distinct upwelling events along the Bonney Coast. Each event surpassed its predecessor in terms of area of influence, minimum temperature and duration. All of the three events developed quickly, with a 5-fold increase of spatial extent within the first 48 hours. The EAC’s areal extent mapped between July 2015 and Sept 2017 showed clear seasonal and intra-seasonal variations. During summer, the EAC and its extension frequently encroached into the coastal areas of northern NSW and eastern Tasmania. The encroachment to the coastal area of southern NSW was more sporadic. A composite analysis based on MJO phases during the summer seasons of 2015–16 and 2016–17 showed that the dSST typically peaked during phases 2 and 3 off the northwest shelf, prior to the onset of the active phases of MJO (phase 4). The analysis indicated that dSST is negatively correlated with the surface wind speed but positively correlated with short-wave latent heat flux. In future, these monitoring and analytical capabilities can be effectively implemented in Geoscience Australia’s Digital Earth Australia platform. Presented at the 2018 Australian Coastal and Oceans Modelling and Observations Workshop (ACOMO)

  • The Roebuck Basin and the adjoining Beagle and Barcoo sub-basins are underexplored areas on Australia’s North West Shelf that are undergoing renewed exploration interest since the discovery of oil at Phoenix South 1 in 2014 and subsequent hydrocarbon discoveries in the Bedout Sub-basin. A well folio of 24 offshore wells across the Beagle, Bedout, Rowley and Barcoo sub-basins has been compiled as part of Geoscience Australia’s hydrocarbon prospectivity assessment across the region. It consists of composite well log plots and well correlations that summarise lithology, lithostratigraphy, Geoscience Australia’s newly acquired biostratigraphic and geochemical data as well as results of petrophysical analysis. A revised sequence-stratigraphic interpretation, key petroleum system elements and drilling results are also documented. The wells dominantly target Triassic shoreward facies (Keraudren Formation) as the primary reservoir objective and Jurassic fluvial-deltaic (Depuch Formation) and/or Lower Cretaceous sandy deltaic facies as the secondary objective. The Keraudren Formation sandstones are sealed intra-formationally either by discontinuous units and/or by the regional Cossigny Member. The Jurassic Depuch Formation sandstones are sealed by regional Lower Cretaceous mudstones. Both charge and structure have been identified as critical issues in the Roebuck Basin. In the Beagle Sub-basin, seal integrity and migration pathways are also considered high risk. Well correlations have identified differences in the basin history and provide insights into the distribution of facies and other characteristics of the Jurassic and Triassic successions. <b>Citation:</b> Nguyen Duy, Rollet Nadege, Grosjean Emmanuelle, Edwards Dianne S., Abbott Steve, Orlov Claire, Bernardel George, Nicholson Chris, Kelman Andrew, Khider Kamal, Buckler Tamara (2019) The Roebuck Basin, Beagle and Barcoo Sub-basin well folio. <i>The APPEA Journal</i><b> 59</b>, 920-927.

  • This OGC Web Feature Service (WFS) contains geospatial seabed morphology and geomorphology information for Cairns Seamount within the Coral Sea Marine Park and are intended for use by marine park managers, regulators, the general public and other stakeholders. This web service uses the data product published in McNeil et al. (2023); eCat Record 147998.

  • We consider how our society can use data, information and knowledge of the Earth under a broad definition of geoscience to better connect with the Earth system. This is important in our changing world, in particular how geoscience contributes to our response to the societal impacts of the COVID-19 pandemic. Ultimately, informed decisions utilizing the best geoscience data and information provide key parts of our economic, environmental and cultural recovery from the pandemic. The connection to country and more widely connection to our planet and the greater Earth system that comes from personal experience has been especially challenged in 2020. Much of Australia’s population have been encouraged to stay in our homes, first because of major fires and more recently in response to isolation from the COVID-19 pandemic. Although domestic travel became increasingly allowable, international travel has been restricted for much longer. This has increased the importance of trusted data and information initially from domestic locations and for more extended time between countries that are now less accessible. We discuss ways that geoscience governs our discovery and use of minerals, energy and groundwater resources and builds resilience and adaptation to environmental and cultural change. A broad definition of geoscience also includes positioning and location data and information, such as through integrated digital mapping, satellite data and real-time precise positioning. Important here is sharing, with two-way exchange of data, information and knowledge about the Earth, through outreach in geoscience education programs and interactions with communities across Australia, into neighboring countries in Asia and the Pacific, and across the world. An aspiration is for geoscience to inform social license through evidence-based decisions, such as for land and marine access, for a strong economy, resilient society and sustainable environment. At Geoscience Australia, we have developed a ten years strategic plan (Strategy 2028) that guides us to be a trusted source of information on Australia’s geology and geography for government, industry and community decision making. This will contribute to a safer, more prosperous and well-informed Australia and its connection to neighbouring countries, such as in Asia, as well as people that are better connected to country and our planet. <b>Citation:</b> Hill, S., Thorne, J., Przeslawski, R., Mouthaan, R., Lewis, C. The 'new normal' for geoscience in a post-COVID world: connecting informed people with the Earth. <i>Thai Geoscience Journal</i> Volume 2 (2) 2021, p30-37 021 ISSN-2730-2695; DOI-10.14456/tgj.2021.3

  • A shallow MW 5.3 earthquake near Lake Muir in southwest Western Australia on the 16 September 2018 was followed on the 8 November by a co-located MW 5.2 event in the same region. Sentinel-1 synthetic aperture radar interferograms (InSAR) allowed for the timely identification and mapping of the surface deformation relating to both earthquakes. Field mapping, guided by the InSAR observations, revealed that the first event produced an approximately 3 km-long and up to 0.4 m-high west-facing surface rupture. Five seismic rapid deployment kits (RDKs) were installed in the epicentral region within three days of the 16 September event. These data, telemetered to Geoscience Australia’s National Earthquake Alerts Centre, have enabled the detection and location of more than 750 dependent events up to ML 4.6. Preliminary joint hypocentre relocation of aftershocks using data from RDKs confirms an easterly dipping rupture plane for the first MW 5.3 event. The main shocks were recorded throughout the Australian National Seismic Network, in addition to a local broadband network in the Perth Basin operated by University of Texas at Dallas and the University of Western Australia. These data indicate large long-period ground-motions due to Rg phases and basin amplification. The two main shocks were widely felt within the region, including the Perth metro region (300 km away), with over 2400 online felt reports for the 8 November event. The Lake Muir sequence represents the ninth recorded surface rupturing earthquake in Australia in the past 50 years. All of these events have occurred in the Precambrian cratonic terranes of western and central Australia, in unanticipated locations. Paleoseismic studies of these ruptures found no evidence for regular recurrence of large events on the underlying faults. The events might therefore be considered “one-offs” at timescales of significance to typical probabilistic seismic hazard studies. Presented at 2019 Seismological Society of America Conference, Seattle in the special session on “Central and Eastern North America and Intraplate Regions Worldwide”

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    TOTAL MAGNETIC INTENSITY Total Magnetic Intensity (TMI) data measures variations in the intensity of the Earth's magnetic field, which includes the fields associated with the Earth's core and the magnetism of rocks in the Earth's crust. The data are 'reduced' to highlight those variations caused by the geology in the Earth's crust. TMI data can be used to interpret sub-surface geological structure and has applications in mineral, energy and groundwater studies. HORIZONTAL MAGNETIC GRADIENT SURVEY This dataset was acquired as part of a horizontal magnetic gradient survey, which uses three alkali-vapour magnetometers to measure longitudinal and transverse gradients. These gradients allow for a 'gradient enhanced' grid of the TMI data to be produced with improved near-surface information and reduced noise (such as that arising from diurnal changes in the magnetic field). LINE METADATA Line spacing: 200 m; Line direction: 90 degrees; Total line-kilometres: 65504 km; Nominal flying height (above ground level): 80 m; Acquisition Start Date: 2023-05-21; Acquisition End Date: 2023-09-14;

  • The ca. 1.5–1.3 Ga Roper Group of the greater McArthur Basin is a component of one of the most extensive Precambrian hydrocarbon-bearing basins preserved in the geological record, recently assessed as of 429 million bbl oil (68 million cubic meters of oil) and between 8 and 118 TCF (222.56 billion cubic meters) of gas (in place). It was deposited in an intracratonic sea, referred to here as the McArthur-Yanliao gulf. The Velkerri Formation forms the major deep-water facies of the Roper Group. Trace metal redox proxies from this formation indicate that it was deposited in stratified waters, in which a shallow oxic layer overlay suboxic to anoxic waters. These deep waters became episodically euxinic during periods of high organic carbon export. The Velkerri Formation has organic carbon contents that reach ∼10 wt. %. Variations in organic carbon isotopes are consistent with organic carbon enrichment being associated with increases in primary productivity and export, rather than flooding surfaces or variations in mineralogy. Although deposition of the Velkerri Formation in an intracontinental setting has been well established, recent global reconstructions show a broader mid to low latitude gulf, with deposition of the Velkerri Formation being coeval with the widespread deposition of organic-rich rocks across northern Australia and northern China. The deposition of these organic-rich rocks may have been accompanied by significant oxygenation associated with such widespread organic carbon burial during the Mesoproterozoic. <b>Citation:</b> Grant M. Cox, Alan S. Collins, Amber J. M. Jarrett, Morgan L. Blades, April V. Shannon, Bo Yang, Juraj Farkas, Philip A. Hall, Brendan O’Hara, David Close, Elizabeth T. Baruch; A very unconventional hydrocarbon play: The Mesoproterozoic Velkerri Formation of northern Australia. <i>AAPG Bulletin</i> 2022;; 106 (6): 1213–1237. doi: https://doi.org/10.1306/12162120148

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    The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). 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 radiometric uranium grid has a cell size of degrees (approximately 40m) and shows uranium element concentration of the Yathong airborne magnetic gradient and radiometric survey, 2023 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2023 by the NSW Government, and consisted of 65504 line-kilometres of data at 200m line spacing and 80m terrain clearance.

  • This service represents models of the structure and composition of the lithospheric mantle. The service currently delivers grids generated from modelling of the structure and composition of the lithospheric mantle at an Australian continental scale using the LitMod platform.

  • <div>The recent federal funding of the <em>National Space Mission for Observation</em> is in no small part a recognition of the capability of the Australian EO community and central to this is the ability to mount effective national-scale field validation programs.</div><div><br></div><div>After many delays, Landsat 9 was launched on the 27th September 2021. Before being handed to the USGS for operational use, NASA had oversight of configuring and testing the new platform and navigating it into its final operational orbit.&nbsp;For a brief few days and a handful of overpasses globally, Landsat 9 was scheduled to fly ‘under’ its predecessor Landsat 8. &nbsp;This provided the global EO community a ‘once in a mission lifetime’ opportunity to collect field validation data from both sensors.</div><div><br></div><div>At short notice the USGS were advised on the timing and location of these orbital overpasses. &nbsp;For Australia, this meant that between the 11th and 17th&nbsp;of November we would see a single overpass with 100% sensor overlap and three others that featured only 10% overlap. Geoscience Australia (who have a longstanding partnership with the USGS on satellite Earth observation) put out a call to the Australian EO community for collaborators.</div><div><br></div><div>Despite this compressed timeline, COVID travel restrictions and widespread La Niña induced rain and flooding, teams from CSIRO, Queensland DES, Environment NSW, University of WA, Frontier SI and GA were able to capture high value ground and water validation data in each of the overpasses.</div><div><br></div><div>Going forward, the Australian EO community need to maintain and build on these skills and capabilities such that the community can meet the future demands of not only our existing international EO collaborations but the imminent arrival of Australian orbiting EO sensors. Abstract presented at Advancing Earth Observation Forum 2022 (https://www.eoa.org.au/event-calendar/2021/12/1/advancing-earth-observation-aeo-2021-22-forum)