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No abstract available

The Geophysical Processing and Data Access (GPDA) project at Geoscience Australia has undertaken a programme of collating, editing and cataloguing all bathymetry data in the Australian Region. For convenience this region has been loosely defined as extending from 5°S to 80°S and 45°E to 180°E. The contents of the Bathymetric Database consists of four datatypes: - Multibeam Echosounder Data (including LADS) - Singlebeam Echosounder Data - Depths from the digitisation of pre-existing maps - Depths derived from remote sensing techniques (and produced grids) The dataset described by this metadata record is the Digitised Bathymetric Maps Dataset. The history of this dataset is somewhat convoluted as the digitising has been conducted by a number of organisations over a number of years using a variety of approaches. Essentially the dataset consists of any bathymetric data that were acquired by GA as the result of digitising a paper based map (or its electronic image). The types of maps that have been digitised include - AHS Fairsheets - AHS/Admiralty and IHO Charts (supplied by AHS) - NATMAP Bathymetric Series Maps (supplied by AHS) - State government Department of Works Maps - Miscellaneous maps produced by other organisations The data digitised by the AHS are supplied to GA in AHS Hydrographic Transfer Format (.htf). This ASCII based format has excellent metadata header records and a uniform organisation of the depth data, making them ideal for incorporation into a relational database. In addition the AHS have supplied Geotif images of the original maps (Fairsheets and Charts) that were used to produce the .htf files as well as ESRI Shapefiles that show the data extent and metadata for each of the original maps. These form an additional layer of metadata which can be used to aid data discoverability and quality control. The other sources of digitised map data are much less in number and data volume and generally do not come with the ancillary information (metadata, images and Shapefiles). Where possible these extra information have been produced at GA to maintain consistency with the AHO datasets. As at April 2007, the numbers of digitised maps are 2200 in number.

The GEBCO "One-Minute Grid" is based on the most recent version of the GEBCO Digital Atlas (GDA) bathymetric contours. Additional control contours and sounding data were used in many regions, particularly shallow water areas and semi-enclosed seas, to constrain the gridding process. It is a continuous digital terrain model for ocean and land, with land elevations derived from the Global Land One-km Base Elevation (GLOBE) database. As GA is only interested in the bathymetry in the Australian Region, the downloaded file was edited so that only the values in the Extents Box remained. The extract extends from 5°S to 80°S and from 45°E to 180°E. It must be stressed that although the GEBCO One Minute Grid is presented at one minute intervals of latitude and longitude, this does not imply that knowledge is available on sea floor depth at this resolution. It is important to note that, in most places, many miles exist between adjacent ship tracklines and that the grid is an interpolation based upon the input data. Further details of the data compilation and GEBCO grid construction are available from the 'User guide to the GEBCO One Minute Grid' ( http://www.bodc.ac.uk/data/online_delivery/gebco/documents/gridhelp.pdf).

This resource contains a probability of occurrence grid of macro algae for the greater Darwin Harbour region as part of a baseline seabed mapping program of Darwin Harbour and Bynoe Harbour. This project was funded through offset funds provided by an INPEX-led Ichthys LNG Project to the Northern Territory Government’s Department of Environment and Natural Resources (NTG-DENR) with co-investment from Geoscience Australia (GA) and the Australian Institute of Marine Science (AIMS). The intent of this program is to improve knowledge of the marine environments in the Darwin and Bynoe Harbour regions by collating and collecting baseline data that enable the creation of thematic habitat maps and information to underpin marine resource management decisions. The probability of occurrence grid of macro algae was derived from a compilation of multiple surveys undertaken by GA, AIMS and NTG-DENR between 2011 and 2017, including GA0333 (Siwabessy et al., 2015), GA0341 (Siwabessy et al., 2015), GA0351/SOL6187 (Siwabessy et al., 2016), GA4452/SOL6432 (Siwabessy et al., 2017), GA0356 (Radke et al., 2017), and GA0358 and GA0359 (Radke et al., 2018), adding to those from a previous survey GA0333 collected by GA, AIMS and NTG-DENR.

Geoscience Australia undertook a marine survey of the Vlaming Sub-basin in March and April 2012 to provide seabed and shallow geological information to support an assessment of the CO2 storage potential of this sedimentary basin. The survey was undertaken under the Australian Government's National CO2 Infrastructure Plan (NCIP) to help identify sites suitable for the long term storage of CO2 within reasonable distances of major sources of CO2 emissions. The Vlaming Sub-basin is located offshore from Perth, Western Australia, and was previously identified by the Carbon Storage Taskforce (2009) as potentially highly suitable for CO2 storage. The principal aim of the Vlaming Sub-basin marine survey (GA survey number GA334) was to look for evidence of any past or current gas or fluid seepage at the seabed, and to determine whether these features are related to structures (e.g. faults) in the Vlaming Sub-basin that may extend up to the seabed. The survey also mapped seabed habitats and biota in the areas of interest to provide information on communities and biophysical features that may be associated with seepage. This research addresses key questions on the potential for containment of CO2 in the Early Cretaceous Gage Sandstone (the basin's proposed CO2 storage unit) and the regional integrity of the South Perth Shale (the seal unit that overlies the Gage Sandstone). This dataset comprises chlorin analyses (total chlorins and chlorin indices) from seabed sediments (0-2 cm).

Bathymetric map showing geological features with contours in metres. Includes Australian Fishing zone limit, seismic survey lines, petroleum exploration wells, for seabed south east of Eyre, W.A., Great Australian Bight, including Eyre Terrace and South Australian Abyssal Plain. Index to adjoining sheets, reliability diagram and locality map. Project coordination by C.R. Johnston, J. Williams, B. Willington ; data compilation D. Jongsma, H.L. Davies. "A joint project of the Hydrographic Service, RAN, Department of Defence, the Bureau of Resource Sciences and the Australian Geological Survey Organisation".

Geoscience Australia undertook a marine survey of the Vlaming Sub-basin in March and April 2012 to provide seabed and shallow geological information to support an assessment of the CO2 storage potential of this sedimentary basin. The survey was undertaken under the Australian Government's National CO2 Infrastructure Plan (NCIP) to help identify sites suitable for the long term storage of CO2 within reasonable distances of major sources of CO2 emissions. The Vlaming Sub-basin is located offshore from Perth, Western Australia, and was previously identified by the Carbon Storage Taskforce (2009) as potentially highly suitable for CO2 storage. The principal aim of the Vlaming Sub-basin marine survey (GA survey number GA334) was to look for evidence of any past or current gas or fluid seepage at the seabed, and to determine whether these features are related to structures (e.g. faults) in the Vlaming Sub-basin that may extend up to the seabed. The survey also mapped seabed habitats and biota in the areas of interest to provide information on communities and biophysical features that may be associated with seepage. This research addresses key questions on the potential for containment of CO2 in the Early Cretaceous Gage Sandstone (the basin's proposed CO2 storage unit) and the regional integrity of the South Perth Shale (the seal unit that overlies the Gage Sandstone). This dataset comprises bulk organic carbon and nitrogen isotopes and concentrations from seabed sediments (0-2 cm).

Geoscience Australia undertook a marine survey of the Leveque Shelf (survey number SOL5754/GA0340), a sub-basin of the Browse Basin, in May 2013. This survey provides seabed and shallow geological information to support an assessment of the CO2 storage potential of the Browse sedimentary basin. The basin, located on the Northwest Shelf, Western Australia, was previously identified by the Carbon Storage Taskforce (2009) as potentially suitable for CO2 storage. The survey was undertaken under the Australian Government's National CO2 Infrastructure Plan (NCIP) to help identify sites suitable for the long term storage of CO2 within reasonable distances of major sources of CO2 emissions. The principal aim of the Leveque Shelf marine survey was to look for evidence of any past or current gas or fluid seepage at the seabed, and to determine whether these features are related to structures (e.g. faults) in the Leveque Shelf area that may extend to the seabed. The survey also mapped seabed habitats and biota to provide information on communities and biophysical features that may be associated with seepage. This research, combined with deeper geological studies undertaken concurrently, addresses key questions on the potential for containment of CO2 in the basin's proposed CO2 storage unit, i.e. the basal sedimentary section (Late Jurassic and Early Cretaceous), and the regional integrity of the Jamieson Formation (the seal unit overlying the main reservoir). This dataset comprises total chlorin concentrations and chlorin indices from the upper 2cm of seabed sediments.

This dataset contains species identifications of benthic worms collected during survey TAN0713 (R.V. Tangaroa, 7 Oct - 22 Nov 2007). Animals were collected from the Faust and Capel basins and Gifford Guyot with a boxcore, rock dredge, or epibenthic sled. Specimens were lodged at Museum of Victoria in June 2008. Species-level identifications were undertaken by Robin Wilson at the Museum of Victoria and were delivered to Geoscience Australia on 1 Aug 2008. See GA Record 2009/22 for further details on survey methods and specimen acquisition. Data is presented here exactly as delivered by the taxonomist, and Geoscience Australia is unable to verify the accuracy of the taxonomic identifications.