One of the earliest results of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) investigation shortly after the spacecraft began to orbit Mars in 1997 was the discovery of layered rock outcrops reaching deep down into the martian crust in the walls of the Valles Marineris. Since that time, thousands of MOC images have revealed layered rock in a variety of settings--crater floors, canyon interiors, and scarps exposed by faulting and pitting. This spectacular example taken by MOC in 2001 is found on the floor of an impact crater located near the equator in northwestern Schiaparelli Basin (0.15°N, 345.6°W). The image covers an area approximately 3 km (1.9 miles) across and is illuminated by sunlight from the upper left. Layers of uniform thickness and appearance suggest that these materials are ancient sediments, perhaps deposited in water, or perhaps deposited by wind. Wind has subsquently eroded and exposed the layers. Dark drifts of sand occur at the lower center of the image, and lighter-toned windblown ripples dominate the center and upper right.

Photo Credit: NASA/JPL/Malin Space Science Systems