The National ASTER Map of Australia is the parent datafile of a dataset that comprises a set of 14+ geoscience products made up of mosaiced ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) scenes across Australia.

ASTER calibration, processing and standardisation approaches have been produced as part of a large multi-agency project to facilitate uptake of these techniques and make them easily integrated with other datasets in a GIS.

Collaborative research, undertaken by Geoscience Australia, the Commonwealth Scientific Research Organisation (CSIRO) and state and industry partners, on the world-class Mt Isa mineral province in Queensland was completed in 2008 as a test-case for these new methods.

For parent datafile information, see the dataset record: http://pid.geoscience.gov.au/dataset/ga/74347

Band ratio: B4/B3

- Blue is low abundance,

- Red is high abundance

Useful for:

(1) Exposed iron ore (hematite-goethite). Use in combination with the “Opaques index” to help separate/map dark:

(a) surface lags (e.g. maghemite gravels) which can be misidentified in visible and false colour imagery; and

(b) magnetite in BIF and/or bedded iron ore; and

(2) Acid conditions: combine with FeOH Group content to help map jarosite which will have high values in both products.

Mapping hematite versus goethite mapping is NOT easily achieved as ASTER’s spectral bands were not designed to capture diagnostic iron oxide spectral behaviour.

However, some information on visible colour relating in part to differences in hematite and/or goethite content can be obtained using a ratio of B2/B1 especially when this is masked using a B4/B3 to locate those pixels with sufficient iro oxide content.

For 'Ferric Oxide Content' dataset information, see the dataset record: http://pid.geoscience.gov.au/dataset/ga/74351

For service status information, see https://status.dea.ga.gov.au