The IRB color image here shows diverse colors. These are infrared-shifted colors, which reveal color distinctions when minerals like olivine are present. Olivine is greenish in natural color but appears blue in the IRB color.
Other rock types are also present, giving the mosaic of colors. This image covers a knob in the Argyre impact structure; HiRISE acquired this image as a “ridealong” to a CRISM target.
Written by: Alfred McEwen (23 February 2011)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_020918_1400
Image: NASA/JPL/University of Arizona