This <a href="//commons.wikimedia.org/wiki/Mars_Global_Surveyor" title="Mars Global Surveyor">Mars Global Surveyor</a> (MGS) Mars Orbiter Camera (MOC) image mosaic was constructed from data acquired by the MOC red wide angle camera. The large, circular feature in the upper left is <a href="//commons.wikimedia.org/w/index.php?title=Aram_Chaos&amp;action=edit&amp;redlink=1" class="new" title="Aram Chaos (page does not exist)">Aram Chaos</a>, an ancient impact crater filled with layered sedimentary rock that was later disrupted and eroded to form a blocky, "chaotic" appearance. To the southeast of Aram Chaos, in the lower right of this picture, is <a href="//commons.wikimedia.org/w/index.php?title=Iani_Chaos&amp;action=edit&amp;redlink=1" class="new" title="Iani Chaos (page does not exist)">Iani Chaos</a>. The light-toned patches amid the large blocks of Iani Chaos are known from higher-resolution MOC images to be layered, sedimentary rock outcrops. The picture center is near 0.5°N, 20°W. Sunlight illuminates the scene from the left/upper left.
<a rel="nofollow" class="external free" href="http://photojournal.jpl.nasa.gov/catalog/PIA04485">http://photojournal.jpl.nasa.gov/catalog/PIA04485</a>