7d9f5199-fa65-4fbc-ba97-6e5e123e3087 urn:uuid eng UTF-8 nonGeographicDataset nonGeographicDataset 2025-10-16T22:01:15 creation ISO 19115 2016 National ASTER Map Opaque index 7d9f5199-fa65-4fbc-ba97-6e5e123e3087 Band ratio: B1/B4 Blue is low abundance, Red is high abundance (potentially includes carbon black (e.g. ash), magnetite, Mn oxides, and sulphides in unoxidised envornments Useful for mapping: (1) magnetite-bearing rocks (e.g. BIF); (2) maghemite gravels; (3) manganese oxides; (4) graphitic shales. Note 1: (1) and (4) above can be evidence for "reduced" rocks when interpreting REDOX gradients. Combine with AlOH group Content (high values) and Composition (high values) products, to find evidence for any invading "oxidised" hydrothermal fluids which may have interacted with reduced rocks evident in the Opaques index product. {"type": "Polygon", "coordinates": [[[111.5, -44.5], [155.0, -44.5], [155.0, -9.0], [111.5, -9.0], [111.5, -44.5]]]} 111.5 155.0 -44.5 -9.0 Earth Observations from Space Earth Sciences HVC_144626 NCI Published_External Remote Sensing Satellite imagery mineralogy Link to data - NCI documentDigital Link to data - NCI XML Link to Digital Earth Australia data page documentDigital Link to Digital Earth Australia data page audio/basic Link to NCI web service documentDigital Link to NCI web service HTML Unnamed resource documentDigital HTML