In this observation from NASA Mars Reconnaissance Orbiter made for a study of ancient craters, we see the craters filled with smooth material that has subsequently degraded into scallops. These formations might be possibly due to ground ice sublimation.
High resolution can help to estimate any differences in roughness on the smoother main mantle and in the eroded hollows. With the enhanced color swath, we might be able to view composition variations of the material.
http://photojournal.jpl.nasa.gov/catalog/PIA19288
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