Advanced Search  |  
 

Geomorphology of the Australian Margin and adjacent seafloor (National Geoscience Dataset)

Note: This metadata describes the dataset in accordance with the ANZLIC (Australia New Zealand Land Information Council) Core Metadata Guidelines Version 2.


Dataset citation

ANZLIC unique identifier: ANZCW0703015075

Title: Geomorphology of the Australian Margin and adjacent seafloor (National Geoscience Dataset)


Custodian

Custodian: Geoscience Australia

Jurisdiction: Australia


Description

Abstract:

The geomorphic features of the seafloor in the Australian Marine Jurisdiction were identified

using the Australian Bathymetry and Topography dataset (Webster & Petkovic 2005). Twenty

one feature types were identified and mapped for an area including the seafloor surrounding the

Australian mainland and island territories of Christmas, Cocos (Keeling), Macquarie, and Norfolk

Islands (Heap & Harris 2008). Some examples of these geomorphic features include: abyssal

plains, trenches, canyons, and seamounts.

ANZLIC search words:

  • MARINE Mapping

Spatial domain:

locality map

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

Geographic bounding box:
North bounding latitude: -8 °
South bounding latitude: -60 °
East bounding longitude: 172 °
West bounding longitude: 92 °

Data currency

Beginning date: 2005-05-31

Ending date: 2005-05-31


Dataset status

Progress: Complete

Maintenance and update frequency: Not Known


Access

Stored data format:
DIGITAL - ArcGIS-grid ArcInfo grid WGS84
Available format type:
DIGITAL - ArcGIS-grid ArcInfo grid WGS84

Access constraints:

This material is released under the Creative Commons Attribution 3.0 Australia Licence.

Free Data Download

Data quality

Lineage:

Initially, 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 original bathymetry database contained more than 200

million data points from 931 marine surveys (Petkovic & Buchanan 2002). A further 87.5 million

data points were added for a later study by Heap & Harris (2008). These additional data points

were extracted from the new bathymetry model of the Australian margin and adjacent seafloor

(Webster & Petkovic 2005). The geomorphic features are defined by the International

Hydrographic Office (IHO, 2001), with one additional feature identified as type 21 ?

Sandwave/Sand bank (Heap & Harris 2008). The geomorphic features 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 km in length.

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), with the

addition of one extra feature type; type 21 ? Sandwave/Sand bank. 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.


Contact information

Contact organisation: Commonwealth of Australia (Geoscience Australia) (GA)
Contact position: Manager Client Services
Mail address: Cnr Jerrabomberra Ave and Hindmarsh Dr
Mail address: GPO Box 378
Locality: Canberra
State: ACT
Country: Australia
Postcode: 2601
Telephone: 02 6249 9966
Facsimile: 02 6249 9960
Electronic mail address: sales@ga.gov.au

Metadata information

Metadata date: 2013-03-08


Additional metadata

Metadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703015075.html

Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703015075.xml

Heap, A. D. and Harris, P. T. 2008. Geomorphology of the Australian margin and adjacent

seafloor. Australian Journal of Earth Sciences, Vol. 55 Issue 4, pp 555-585.

Authors:Heap, A.D. Harris, P.
SPATIAL INFORMATION FOR THE NATION