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Geomorphic Features 2006Note: This metadata describes the dataset in accordance with the ANZLIC (Australia New Zealand Land Information Council) Core Metadata Guidelines Version 2. Dataset citationANZLIC unique identifier: ANZCW0703014955 Title: Geomorphic Features 2006 CustodianCustodian: Geoscience Australia Jurisdiction: Australia DescriptionAbstract: The data set provides outlines for the maximum extent of geomorphic units for the North West Marine Region. The dataset is clipped from Geoscience Australia's original Geomorphic Features of Australia's Exclusive Economic Zone (EEZ) to the East Marine Region extent. These data were compiled as part of Geoscience Australia's integrated digital information system to provide improved accessibility and knowledge relating to the environmental management of Australian's oceans resources. The geomorphic units are to be used as surrogates for benthic habitats and can be best applied to the construction of bioregionalisations of the seabed. The data set also includes the name of units in the attribute table, where known, the source(s) of the names, feature codes, province codes, as well as the area and perimeter of each unit. The data are accompanied by Geoscience Australia Record 2003/30. Dataset has been updated (2006) to correct errors in original file. ANZLIC search words:
Spatial domain:
Geographic extent name: AUSTRALIA EXCLUDING EXTERNAL TERRITORIES - AUS - Australia - Australia Geographic extent polygon: 92 -8, 172 -8, 172 -60, 92 -60, 92 -8, Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Data currencyBeginning date: 2006-01-01 Ending date: 2009-11-01 Dataset statusProgress: Complete Maintenance and update frequency: Not Known Access
Access constraints: This material is released under the Creative Commons Attribution 3.0 Australia Licence. Free Data DownloadData qualityLineage: The geomorphic features were captured in 2002 as part of a program run by Geoscience Australia and the National Oceans office to create a spatial inventory of benthic habitats for Australia?s marine jurisdiction. The geomorphic features are defined by the International Hydrographic Office (IHO, 2001), and were identified using a 250 m spatial resolution bathymetry model with reference to previously published geological studies. In most cases, the feature boundaries corresponded to already published boundaries or were defined based on obvious bathymetric features, supplemented by high-resolution seismic reflection and sedimentary data. Where appropriate, the feature boundaries and classifications are consistent with United Nations Law of the Sea boundaries. The identification of shelf valleys and submarine canyons on the continental slope was aided by the use of predicted drainage maps. All the features were identified on the contour and false colour maps and drawn by hand onto transparent compilation maps. When completed, the compilation maps were scanned, georeferenced and the separate polygons were digitised and stored as an ARC/GIS shape file. Care was taken where separate maps sheets joined to ensure that features were correctly identified and retained their identity across the boundaries. Positional accuracy: Positional accuracy of individual geomorphic features boundaries varies depending on the source data. Due to the scale of the map, and quality of the source, the smallest feature that could be reliably resolved was approximately 10 sq km. Attribute accuracy: No attribute for data quality exists at this stage. This attribute will be updated once a reliability map for the source bathymetric data has been generated. The reliability map will be based on the spatial distribution of soundings. Logical Consistency: All bathymetric datasets once reduced to 9 x 250 m grids for the Australia EEZ were examined visually for data consistency. In some circumstances individual datasets were identified as inconsistent within the grid and either left out of the final grid or were corrected. Terms and nomenclature used to describe geomorphic features of the seabed are based on definitions endorsed by the International Hydrographic Organisation (IHO, 2001). Adopting ISO terms ensures a standard nomenclature that is widely recognised. Regional data sets were then compiled as a single national coverage. Tests were also carried out on the data for completeness, correct spatial representation, attribute accuracy, and logical consistency and correctness. Completeness: Coverage: The geomorphic units cover 100% of the Australia Exclusive Economic Zone. The raw data that makes up the bathymetry grid is derived from numerous sources and has been obtained opportunistically hence the actual data coverage is generally patchy and irregular. A data density map for the bathymetry grids has not yet been produced. Classification: A total of 21 separate categories of geomorphic feature were selected for mapping (IHO, 2001). A category for sandwaves and sand banks were also included to capture important geomorphic features on the shelf. Terms and nomenclature used to describe geomorphic features of the seabed are based on definitions endorsed by the International Hydrographic Organisation (IHO, 2001). Further details of these terms and documentation underlying their adoption by IHO may be found at the following internet address: http://www.iho.shom.fr/publicat/free/files/ B6efEd3.pdf for complete IHO documentation (IHO, 2001). Due to the often sparse nature of the bathymetric data and the coarse resolution of the maps some features in the geomorphic units map were identified through a literature search and not directly from the bathymetry grids. This was often the case for features such as sandwaves on the shelf, which occur on a scale to small to be resolved within the 250 m bathymetry grid. Verification: Field verification was limited to reviewing published literature of prominent marine features within the Australian EEZ. Contact information
Metadata informationMetadata date: 2013-04-15 Additional metadataMetadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703014955.html Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703014955.xml . Authors:Heap, A.D. Harris, P. Sbaffi, L. Passlow, V. Fellows, M. |
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