Ice-rich mantling deposits accumulate from the atmosphere in the Martian mid-latitudes in cycles during periods of high obliquity (axial tilt), as recently as several million years ago.
These deposits accumulate over cycles in layers, and here in the southern mid-latitudes, where the deposits have mostly eroded away due to warmer temperatures, small patches of the remnant layered deposits can still be observed.
The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 29.5 centimeters (11.6 inches) per pixel (with 1 x 1 binning); objects on the order of 89 centimeters (35 inches) across are resolved.] North is up.
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington.
Image credit: NASA/JPL-Caltech/Univ. of Arizona