Central Valles Marineris
This observation shows a landslide scarp on the northern wall of central Valles Marineris, a large canyon system equivalent in length from California to New York.
The landslide has exposed a fresh wall of the canyon so that individual layers of rock can be seen. The texture of these layers suggests that some of the darker rock layers are more resistant to erosion than the lighter layers. The variation in brightness and friability of the different layers suggests compositional differences. These layers may have a volcanic origin, having been deposited as ash layers, or a sedimentary origin, either being deposited by water or blown by the wind (aeolian).
This image is a little hazy because this image was taken in August 2007, when the large dust storm covered the surface of Mars and filled the atmosphere with fine dust particles. The extra dust in the atmosphere reflects more light into the camera.