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Digital files for the Index of airborne geophysical surveys, twelfth edition, October 2011 releaseNote: 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: ANZCW0703015557 Title: Digital files for the Index of airborne geophysical surveys, twelfth edition, October 2011 release CustodianCustodian: Geoscience Australia Jurisdiction: Australia DescriptionAbstract: The twelfth edition of the Airborne Geophysical Survey Index presents a summary of the essential specifications of over 1080 surveys held in the National Airborne Geophysical Database. Includes Index Maps at 1:10 million scale for magnetic and radiometric survey coverage of Australia as at 31 August 2011. ANZLIC search words:
Spatial domain:
Geographic extent name: AUSTRALIA EXCLUDING EXTERNAL TERRITORIES - AUS - Australia - Australia Geographic extent polygon: 110 -8, 154 -8, 154 -44, 110 -44, 110 -8, Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Data currencyBeginning date: 2011-08-31 Ending date: 2011-08-31 Dataset statusProgress: In Progress Maintenance and update frequency: Not Known Access
Access constraints: Free to download Free Data DownloadData qualityLineage: This is an information dataset giving specifications on airborne geophysical data available from Geoscience Australia, State and Territory Geological Surveys and public domain company data. Further information on this dataset can be obtained from the following source : Percival, P.J. (compiler), 2011. "Index of Airborne Geophysical Surveys (Twelfth Edition)" - Geoscience Australia Record 2011/36 Positional accuracy: Before the introduction of GPS, radio-navigation beacons were used for navigation. Prior to radio-navigation the location of the aircraft was determined by comparing strip film or video recordings made of the ground during flight with aerial photography and topographic maps. In the latter case, an accuracy of the order of 150m was claimed for each of the points (called fixes) picked from the film/video record and located on topographic maps. Three to four fixes were determined at the start and end of each line and then at regular intervals along it. Intermediate points were infilled with additional naviagtional data recorded on the aircraft Doppler navigation system. With the advent of GPS positional accuracies of 15m are routine. Survey boundaries are accurately located using geodetic coordinates (longitude, latitude). Attribute accuracy: Either the Owner of the survey data or the Contractor that acquired the survey data supplied survey metadata attributes. Attributes are sourced from operational reports supplied by the Contractor or from documentation supplied by the Owner of the survey data. The attribute accuracy is only as accurate as he information supplied by the survey contractor or survey operator. Logical Consistency: The GIS package (Mapinfo) was used to detect errors in the spatial data structure. This check ensures that all survey polygons are closed and that each polygon is uniquely identified. A visual check of the survey metadata attributes is done prior to release. Completeness: 1083 surveys are contained in the 12th edition of the Index of Airborne Geophysical Surveys (October 2011 release), but of these only 986 have survey polygon information. The remaining 97 surveys were most ly flown in the 1950's and 1960's for which no reliable spatial digital data is available. Most attributes are available for all the surveys included in this GIS dataset . Contact information
Metadata informationMetadata date: 2013-03-08 Additional metadataMetadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703015557.html Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703015557.xml . Authors:Percival, P.J. |
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