Continuing with this series of the naive photo-interpreter using Copernicus Browser, another interesting feature is the presence of many pre-calculated indices.
Considering geology and arid zones, a few useful pre-calculated indices are SWIR (Short-Wave Infrared Composite, bands B12, 8A and 4) and False Color (Urban, B12, 11 and 4).
The shown examples come from the South-Eastern Libyan desert, almost to the boundary with Egypt.
As you can see, the natural color image does not evidence particular lithological differences within the outcropping structure surrounded by sands.
Using the SWIR index, lithological boundaries and contacts are much more evident and can be used to draft a first preliminary geological interpretation, where there are volcanic and possibly sedimentary rocks.
Also False Color (Urban), using bands B12, 11 and 4 differentiate between lithologies.
Considering instead the different types of sands, NDSI (Normalised Difference Snow Index, bands 3, 11, 4 and 2) is particularly useful: the 'rivers' of younger and brighter sands around the older sand deposits are clearly evident.
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