Dark, windblown sand covers intricate sedimentary rock layers in this image from Ganges Chasma, a canyon in the Valles Marineris system.
These features are at once familiar and unusual to those familiar with Earth’s beaches and deserts. Most sand dunes on Earth are made of silica-rich sand, giving them a light color; these Martian dunes owe their dark color to the iron and magnesium-rich sand found in the region.
Written by: Kristin Block (25 April 2017)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_019507_1725
Image: NASA/JPL/University of Arizona