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: B5/B7

- Blue is well ordered kaolinite, Al-rich muscovite/illite, paragonite, pyrophyllite

- Red is Al-poor (Si-rich) muscovite (phengite)

Useful for mapping:

(1) exposed saprolite/saprock is often white mica or Al-smectite (warmer colours) whereas transported materials are often kaolin-rich (cooler colours);

(2) clays developed over carbonates, especially Al-smectite (montmorillonite, beidellite) will produce middle to warmers colours;

(3) stratigraphic mapping based on different clay-types; and

(4) lithology-overprinting hydrothermal alteration, e.g. Si-rich and K-rich phengitic mica (warmer colours).

Combine with Ferrous iron in MgOH and FeOH content products to look for evidence of overlapping/juxtaposed potassic metasomatism in ferromagnesian parents rocks (e.g. Archaean greenstone associated Au mineralisation) +/- associated distal propyllitic alteration (e.g. chlorite, amphibole)

For 'AlOH Group Composition' dataset information, see the dataset record: http://pid.geoscience.gov.au/dataset/ga/74356

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