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Australian Crustal Elements (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 citationANZLIC unique identifier: ANZCW0703002384 Title: Australian Crustal Elements (National Geoscience Dataset) CustodianCustodian: Geoscience Australia Jurisdiction: Australia DescriptionAbstract: The Australian Crustal Elements dataset delineates upper crustal elements, primarily based on composite geophysical domains, each of which shows a distinctive pattern of magnetic and gravity anomalies. These elements generally relate to the basement, rather than the sedimentary basins.Boundaries between these elements are interpreted to mark crustal-scale changes in composition or structural pattern, or both. Where feasible, these boundaries are chosen to emphasise their correlation with the outcropping boundaries of geological provinces. The principles used to construct this map are based on the research, in Australia, by a large number of workers including Fraser et al. (1977), Wellman (1976a, 1976b, 1978), Tucker et al. (1979) and Mathur and Shaw (1982). Similar research overseas includes the work of Provodnikov (1975), Thomas et al. (1988) and Rivers (1989). In attempting to build the model for the tectonic framework of the continent, AGSO began by looking for coherence between gravity and magnetic domains to delineate composite geophysical domains. After analysing several portrayals of amalgamated magnetic and gravity data sets, compositional and structural province-scale boundaries were erected that correlate, where possible, with geological features. Such boundaries can then be extrapolated under the sedimentary basins. To give the map an added tectonic flavour, the domains were characterised according to their magnetic and gravity character, in a way that reflects the tectonic significance of their magnetic responses. Further information: Due to the complexity of this data set a Microsoft Word for Windows 95 document (crustel.doc) is also supplied for additional information to what is contained within this metadata. ANZLIC search words:
Spatial domain:
Geographic extent name: AUSTRALIA EXCLUDING EXTERNAL TERRITORIES - AUS - Australia - Australia Geographic extent polygon: 113 -11, 153 -11, 153 -42, 113 -42, 113 -11, Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Data currencyBeginning date: Not Known Ending date: 1998-09-01 Dataset statusProgress: Complete Maintenance and update frequency: Not Known Access
Access constraints: Free to download Free Data DownloadData qualityLineage: Crustal element interpretation of current gravity and magnetics image data was digitised initially in Microstation (Integraph) and subsequently ported into Arcinfo, dictating the gravity, magnetic and resultant polgyon coverage of crustal elements. Attributes were added to the polgon and arc coverages after this. Gravity data 1.National Gravity Database derivative integrated ' 2.5km (91.5 minute) gridded format' 2.Contoured Bouger anomaly contour maps plotted at ' 1:2 500 000 scale' 3.Enhanced images of Bouger anomalies at 1:5 000 000 scale Magnetics data 1.National Magnetics Database derivative 1:1 000 000/1:2 500 000 ' scale contour maps' 2.Various scale anomaly images 3.Magnetic Anomaly 1:5 000 000 scale map of Australia, showing ' gradient enhanced residuals of total intensity' Positional accuracy: Nominal Scale 1:5,000,000 Attribute accuracy: Moderate Logical Consistency: A geoscientist visually inspected the finished dataset to make sure the attributes were accurate and the data were consistent spatially with current scientific information. Tests are also carried out on these data for data completeness, correct spatial representation, attribute accuracy, logical consistency and correctness, and where appropriate for compliance with Geoscience Australia's GIS data dictionary. Completeness: The dataset coverage is complete for the whole of continental Australia. Contact information
Metadata informationMetadata date: 2013-03-08 Additional metadataMetadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703002384.html Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703002384.xml "Users guide to the Australian Crustal Elements Map", AGSO Record 1996/30. Crustal Elements (polygon items : CETEC) NOTE : CEELM is a dataset derived from the Mega_elem attribute of the CETEC dataset Feature Feature type. UFI Unique feature identifier Polylabel These are an ID for colour-groupings used for plotting. TectUnit These are tectonostratigraphic-like units, based on a cross-correlation between geophysical Elem_Type (magnetic type) and Elem_Age. Elem_Ref It is the primary crustal element ID Elem_Name An informal name for the crustal element. Rank The crustal elements are ranked in hierarchical order by their size and significance into enclosed polygon regions. Desc This free-text field provides details about any correlation between the crustal element [geophysical domain] and any basement province, tectonic feature or other region. Basins This free-text field list the sedimentary basins that overlie each crustal element. Elem_Age This numerical field lists the relative deduced age of elements. Geo_Ovrprnt This numerical field gives the relative age-range of any overprinted geophysical signature. Elem_Type The elements are classified, mainly on their magnetic character or type, into the following: Mega_Elem These are groups of related elements that represent cratonic regions. Relict This numerical field gives the deduced relative age for rock units presumed to be the source of older, locally mapped, geophysical patterns. Arc_Col_ID This attribute can be used with the Arc/Info format of the data to produce a plot using the Agso94.shd shadeset. Overprint This field is a 'yes' or 'no' attribute signifying the graphic display of the overprint. Magnetic Boundaries and Gravity boundaries datasets (line items: CEGRAV and CEMAG) Feature Feature Type, eg; CRUST_BOUND UFI Unique Feature Identifier Mag_Code Numeric type Identifier Desc Type of boundary Class Status of boundary Authors:Shaw, R. Hay, R. |
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