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  • High-resolution marine sonar swath mapping, covering an area of ca. 33 km2 in the vicinity of the Windmill Islands (67° S, 110° E), Wilkes Land, east Antarctica, permits visualisation and description of the near-shore geomorphology of the seafloor environment in unprecedented detail and provides invaluable insight into the ice-sheet history of the region. Mesoproterozoic metamorphic basement exhibits prominent sets of parallel northwest-trending linear fault sets that probably formed during fragmentation of eastern Gondwana during the Mesozoic. The fault systems appear to control regional coastal physiographic features and have, in places, been preferentially eroded and exploited by subsequent glacial activity. Possibly the earliest formed glacially-derived geomorphological elements are networks of sub-glacial meltwater channels which are preserved on bedrock platforms and ridges. Subtle glacial lineations and streamlined landforms record evidence of the westward expansion of the grounded, Law Dome ice sheet margin, probably during the late Pleistocene Last Glacial Maximum, the direction of which coincides with glacial striae on onshore crystalline bedrock outcrops. The most striking glacial geomorphological features are sets of arcuate ridges confined mostly within glacially excavated `U-shaped valleys, exploiting and developed along bedrock fault sets. These ridge sets are interpreted as `push moraines or grounding zone features, formed during episodic retreat of highly channelised, topographically controlled ice-streams following ice surging, possibly in response to local environmental forcing during the mid-late Holocene. Minor post-glacial marine sedimentation is preserved in several small (1 km2) `isolated marine basins with shallow seaward sills.

  • Map showing Australia's Maritime Jurisdiction off Northern Australia. Updated in June 2014 from "Australia's Maritime Jurisdiction off Northern Australia" (GeoCat 70183) to conform with "Australian Maritime Boundaries 2014" data by Geoscience Australia. This includes areas contiguous to the north of the continent and as far west as Christmas Island, but excludes areas around Cocos (Keeling) Islands and areas west of Christmas Island. One of the 27 constituent maps of the "Australia's Maritime Jurisdiction Map Series" (GeoCat 71789). Depicting Australia's continental shelf as proclaimed in the "Seas and Submerged Lands (Limits of Continental Shelf) Proclamation 2012" established under the "Seas and Submerged Lands Act 1973". Background bathymetry image is derived from a combination of the 2009 9 arc second bathymetry and topographic grid by Geoscience Australia and a grid by W.H.F. Smith and D.T. Sandwell, 1997. Background land imagery derived from Blue Marble, NASA's Earth Observatory. 2800mm x 1050mm (for 42" plotter) sized .pdf downloadable from the web.

  • Map showing all of Australia's Maritime Jurisdiction north of approx 25°S. Updated in June 2014 from "Australia's Maritime Jurisdiction North of 25°S" (GeoCat 71985) to conform with "Australian Maritime Boundaries 2014" data by Geoscience Australia. This includes areas around Cocos (Keeling) Islands and areas around Christmas Island as well as those contiguous to the continent in the north. Included as one of the now 28 constituent maps of the "Australia's Maritime Jurisdiction Map Series" (GeoCat 71789). Depicting Australia's continental shelf as proclaimed in the "Seas and Submerged Lands (Limits of Continental Shelf) Proclamation 2012" established under the "Seas and Submerged Lands Act 1973". Background bathymetry image is derived from a combination of the 2009 9 arc second bathymetry and topographic grid by Geoscience Australia and a grid by W.H.F. Smith and D.T. Sandwell, 1997. Background land imagery derived from Blue Marble, NASA's Earth Observatory. 3277mm x 1050mm (for 42" plotter) sized .pdf downloadable from the web.

  • It is with great interest that we read the paper by Mueller (2015) who proposes that the majority of small pockmarks with diameters less than about 10 m on the northwest shelf of Australia may be of biotic origin, created by the fish Epinephelus, the Grouper. This hypothesis is based on a spatial association between pockmarks and Epinephelus at a number of sites on the northwest shelf and elsewhere around Australia, and on recent work undertaken on the habitats and observed behaviours of grouper fish in the Gulf of Mexico who excavate sediment from pre-existing solution cavities (Coleman et al., 2010; Wall et al., 2011). However, we contend that critical details have not been taken into account as part of Mueller's (2015) hypothesis, and additional consideration of existing geologic, geomorphic, sedimentologic and geochemical information is required. To make the science more robust, here we present a more comprehensive overview of the information available.

  • The Casey shallow-water near-shore seabed mapping survey (survey number GA-0348) was conducted as collaboration between Geoscience Australia (GA, Department of Science and Industry), the Royal Australian Navy (RAN, Department of Defence) and the Australian Antarctic Division (AAD, Department of the Environment). The survey was conducted as part of the ongoing AAD program Hydrographic Surveying and Bathymetric Data Acquisition (AAD 3326) and complements a previous charting survey to the Casey region undertaken by RAN and AAD (using the RAN vessel ASV Wyatt Earp) in 2013/14 (also conducted under AAD 3326). The purpose of the survey was to acquire geophysical, geological and biological data from the seabed environment in the shallow (<250 m) coastal waters adjacent to Casey station. The survey acquisition phase formed the main work program for the Antarctic Geoscience Program and Advice activity as part of the Marine Biodiversity and Antarctic Geoscience (MBAG) Section at Geoscience Australia during 2014/15. The shallow water marine environment around Casey station, East Antarctica, is a high use area in the Australian Antarctic Territory, and is frequently visited by the RSV Aurora Australis and smaller vessels conducting scientific research in the area, yet bathymetry data in the area is limited. Additionally, a long-term dive program has revealed the marine habitats in the area host globally significant levels of biodiversity, but this knowledge is geographically restricted in scope (i.e. shallow depths, close to shore). This biodiversity faces pressures from human activities and climate change, yet extensive knowledge gaps remain, limiting efforts to conserve and manage it effectively.

  • This paper presents an application of a spatially-balanced survey design using baited videos in one reserve in Australia's recently declared network of reserves to: (i) identify the types of demersal fish communities present, (ii) quantify their relationship with environmental gradients and, (iii) describe their spatial distribution across the shelf of the reserve as an essential first step towards developing a monitoring program. Baited videos recorded a range of species from multiple trophic levels, including species of commercial and recreational interest. The majority of species, whilst found commonly along the southern or south-eastern coasts of Australia, were endemic to Australia, highlighting the global significance of this region. We identified six distinct fish assemblages on the shelf of the reserve. The distribution of these assemblages was related to environmental variables, the most important being depth and habitat type. Assemblages could be broadly categorised as either a combination of reef or sand associated and shallow or deep. Species richness was greater on habitats containing some reef and declined with increasing depth. The trophic breath of species in assemblages was also greater in shallow waters. We further discuss how our results can be used to inform future surveys and monitoring within this reserve as well as comment more generally on the utility of our approach for establishing inventories and baselines when little prior knowledge is available.

  • A benthic sediment sampling survey (GA0356) to the nearshore areas of outer Darwin Harbour was undertaken in the period from 03 July to 14 September 2016. Partners involved in the survey included Geoscience Australia (GA), the Australian Institute of Marine Science (AIMS) and the Department of Environment and Natural Resources within the Northern Territory Government (NT DENR) (formerly the Department of Land and Resource Management (DLRM)). This survey forms part of a four year (2014-2018) science program aimed at improving knowledge about the marine environments in the regions around Darwin and Bynoe Harbour’s through the collection and collation of baseline data that will enable the creation of thematic habitat maps to underpin marine resource management decisions. This project is being led by the Northern Territory Government and is supported by the INPEX-led Ichthys LNG Project, in collaboration with - and co-investment from GA and AIMS. The program builds upon an NT Government project (2011-2011) which saw the collection of baseline data (multibeam echosounder data, sediment samples and video transects) from inner Darwin Harbour. This dataset comprises total oxygen uptake and total carbon dioxide flux measurements from core incubation experiments on seabed sediments. Radke, L., Smit, N., Li, J., Nicholas, T., Picard, K. 2017. Outer Darwin Harbour Shallow Water Sediment Survey 2016: GA0356 – Post-survey report. Record 2017/06. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2017.006 This research was funded by the INPEX-led Ichthys LNG Project via the Northern Territory (NT) Government Department of Land Resource Management (DLRM) (now the Department of Environment and Natural Resources (DENR)), and co-investment from Geoscience Australia (GA) and Australian Institute of Marine Science (AIMS). We are grateful to the following agencies for providing boats and staff, and to the following personal for help with sample acquisition: NT DENR (Danny Low Choy and Rachel Groome), NT Fisheries (Wayne Baldwin, Quentin Allsop, Shane Penny, Chris Errily, Sean Fitzpatrick and Mark Grubert), NT Parks and Wildlife (Ray Chatto, Stewart Weorle, and Luke McLaren) and the Larrakia Rangers (Nelson Tinoco, Kyle Lewfat, Alan Mummery and Steven Dawson). Special thanks to the skippers Danny Low Choy, Wayne Baldwin, Stewart Weorle and Luke McLaren whose seamanship strongly guided the execution of this survey. AIMS generously allowed use of the aquarium and laboratory at the Arafura Timor Sea Research Facility, and Simon Harries and Kirsty McAllister helped with the setup. We would also like to acknowledge and thank GA colleagues including: Matt Carey, Ian Atkinson and Craig Wintle (Engineering and Applied Scientific Services) for the organisation of field supplies and the design of the new core incubation set-up. This dataset is published with the permission of the CEO, Geoscience Australia

  • The Seas and Submerged Lands Act (SSLA) 1973 is the Australian legislation that provides the domestic legal framework for Australia to declare its international offshore maritime zones, as provided for by the United Nations Convention on the Law of the Sea (UNCLOS) to which Australia is a party. Proclamations under the SSLA establish the territorial sea baseline, the territorial sea, the contiguous zone, the exclusive economic zone and the continental shelf. This service depicts official spatial representation of these proclamations. The service includes feature layers: Normal and Straight baselines limits and locations; Contiguous Zone and limit; Territorial Sea Zone and limit; Exclusive Economic Zone (EEZ), limits and locations; Continental Shelf limit and locations.

  • The Timor Sea and its tropical marine environment support significant and growing economic activity including oil and gas exploration. To reduce uncertainty in decision making regarding the sustainable use and ongoing protection of these marine resources, environmental managers and resource users require sound scientific information on the composition and stability of seabed environments and their biological assemblages. Surveys SOL4934 and SOL5117 to the eastern Joseph Bonaparte Gulf were undertaken in August and September 2009 and July and August 2010 respectively, in collaboration with the Australian Institute of Marine Science, with research collaborations from the RAN Australian Hydrographic Office, the Geological Survey of Canada and the Museum and Art Gallery of the Northern Territory. The purpose of these surveys were to develop biophysical maps, and deliver data and information products pertaining to complex seabed environment of the Van Diemen Rise and identify potential geohazards and unique, sensitive environments that relate to offshore infrastructure. This dataset comprises mineralogy of bulk and fine (<63 um) seabed sediment fraction (0-2cm). Some relevant publications are listed below: 1. Heap, A.D., Przeslawski, R., Radke, L., Trafford, J., Battershill, C. and Shipboard Party. 2010. Seabed environments of the eastern Joseph Bonaparte Gulf, Northern Australia: SOL4934 Post Survey Report. Geoscience Australia Record 2010/09, pp.81. 2. Anderson, T.J., Nichol, S., Radke, L., Heap, A.D., Battershill, C., Hughes, M., Siwabessy, P.J., Barrie, V., Alvarez de Glasby, B., Tran, M., Daniell, J. & Shipboard Party, 2011b. Seabed Environments of the Eastern Joseph Bonaparte Gulf, Northern Australia: GA0325/Sol5117 - Post-Survey Report. Geoscience Australia, Record 2011/08, 58pp. 3. Radke, L.C., Li, J., Douglas, G., Przeslawski, R., Nichol, S, Siwabessy, J., Huang, Z., Trafford, J., Watson, T. and Whiteway, T. Characterising sediments of a tropical sediment-starved continental shelf using cluster analysis of physical and geochemical variables. Environmental Chemistry, in press

  • Not current – This service has been deprecated in favor of the 2019 epoch, which includes amendments reflecting new boundary arrangements with Timor-Leste, which came into force on 30 August 2019. The Seas and Submerged Lands Act (SSLA) is the Australian legislation that provides the framework for Australia to declare the baselines, limits and zones provided under the first six parts of the United Nations Convention on the Law of the Sea. These baselines, limits and zones are declared by Proclamations provided for under this act. This service depicts official spatial representation of these proclamations. The service includes feature layers: Normal and Straight baselines limits and locations, Contiguous Zone and limit, Territorial Sea Zone and limit, Exclusive Economic Zone (EEZ) and limit, Continental Shelf limit and locations. NOTE: There are two versions of the Exclusive Economic Zone (EEZ) provided. One depicts the EEZ as proclaimed in the Seas and Submerged Lands Act 1973 - Proclamation under section 10B (26/07/1994). The second version includes amendments reflecting the provisions of the signed but not unratified Treaty between the Government of Australia and the Government of the Republic of Indonesia, establishing an Exclusive Economic Zone Boundary and Certain Seabed Boundaries (Perth, 14 march 1997) [1997] ATNIF 9 - (not yet in force). (Perth Treaty). The version reflecting Perth Treaty EEZ limits and area should be the standard depiction.