We describe a method to obtain the principal components of a multispectral image. It allows a simultaneous radiometric enhancement by means of a suitable finer level quantization that does not introduce artifacts. Using this method we are able to produce good photographic prints of the principal components of LANDSAT MSS images. As a matter of fact the two first components (that we call bands A and B) alone contain nearly all the information existing on the original image while the other contain only noise.

We use this technique to help in the geological study of Campo Arañuelo Basin, in Central Spain aimed to confirm the hypothesis of different geological histories since Miocene times of this area and the remainder of Tajo Basin.

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