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Magnetic anomaly map of Australia, fourth edition, 1:25million scale, 2004Note: 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: ANZCW0703007142 Title: Magnetic anomaly map of Australia, fourth edition, 1:25million scale, 2004 CustodianCustodian: Geoscience Australia Jurisdiction: Australia DescriptionAbstract: This edition of the Magnetic anomaly map of Australia results from a completely new compilation of Total Magnetic Intensity (TMI) grid data. It has been produced using a new method of matching the individual survey grids and the use of independent data to help constrain long wavelengths. 680 individual grids have been matched and merged into the composite used to produce this image, with the resolution of each grid optimal for the specifications of the source survey line data. Since the Third Edition (Milligan and Tarlowski, 1999), data from many new surveys have been added, acquired mainly by the State and Territory geological surveys. It is estimated that 19 million line-kilometres of survey data were acquired to produce the grid data, 10 million line-kilometres more than for the Third Edition. ANZLIC search words:
Spatial domain:
Geographic extent name: AUSTRALIA EXCLUDING EXTERNAL TERRITORIES - AUS - Australia - Australia Geographic extent polygon: 112 -10, 155 -10, 155 -45, 112 -45, 112 -10, Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Data currencyBeginning date: 1950-01-01 Ending date: 2004-09-30 Dataset statusProgress: Complete Maintenance and update frequency: Not Known Access
Access constraints: Copyright Geoscience Australia 2004 Order ProductData qualityLineage: This edition of the Magnetic anomaly map of Australia results from a completely new compilation of Total Magnetic Intensity (TMI) grid data. It has been produced using a new method of matching the individual survey grids and the use of independent data to help constrain long wavelengths. 680 individual grids have been matched and merged into the composite used to produce this image, with the resolution of each grid optimal for the specifications of the source survey line data. Since the Third Edition (Milligan and Tarlowski, 1999), data from many new surveys have been added, acquired mainly by the State and Territory geological surveys. It is estimated that 19 million line-kilometres of survey data were acquired to produce the grid data, 10 million line-kilometres more than for the Third Edition. Positional accuracy: The positional accuracy is highly variable depending on the age of the individual surveys that comprise this dataset. Prior to 1990, data were usually collected using photographic flight path recovery which has an accuracy of plus or minus 100 metres. More recent surveys were acquired using differential GPS giving accuracy better than 5 metres. Surveys acquired with a line spacing less than or equal to 400 metres usually represent these newer surveys. Attribute accuracy: Highly variable depending on the age of the individual surveys that comprise this dataset. Prior to 1990, survey data were acquired using proton procession magnetometers, which have an accuracy of plus or minus 0.1 to 5 nT (nano Tesla's), or fluxgate magnetometers which make relative measurements and have a precision of better than 0.1nT. Modern surveys after this time used helium or caesium magnetometers which have an accuracy of 0.1 nano Tesla's or better. Surveys acquired with a line spacing less than 400 metres usually represent these newer more accurate surveys. Logical Consistency: This map was produced from the Magnetic Anomaly Grid of Australia (Fourth Ed.) which was made by stitching together grids derived from airborne geophysical surveys. The grids from adjoining individual surveys were stitched together using polynomial corrections in such a way as to minimise differences in the overlapping regions. Smaller errors are then smoothed at the join. 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/ANZCW0703007142.html Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703007142.xml Refer to this map as: Milligan, P.R. and Franklin, R. 2004. Magnetic anomaly map of Australia (Fourth ed.), 1:25 000 000 scale, Geoscience Australia, Canberra. Authors:Milligan, P.R. Franklin, R. |
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