On the Edge of the South Pole Layered Deposit

This image shows the edge of the Martian South Polar layered deposit. The stack of fine layering is highlighted by the rays of the polar sun.

These layers show the pervasive red coloring of Mars which have built up over the ages. While this is a polar deposit, no ice or frost is visible on these layers, as they face the sun. However, if you look beyond the rim of the layered slope at the 'top' of the deposit, you can see that red rock and dust are covered with frost, as well as small radial channels that are evidence of polar spider networks.

http://photojournal.jpl.nasa.gov/catalog/PIA21105