11 September 2004
An impact crater in western Arabia Terra at 8°N, 7°W, exhibits some of the most fantastic sedimentary rock outcrops on Mars. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example. The crater interior has hundreds of sedimentary rock layers, each of a similar thickness and similar physical properties. The similarities between beds and their repeated nature have been used to suggest that the crater was once the site of a lake. Today, the sedimentary rocks are eroded and dark, windblown sand covers some of them. Faults cut and offset beds in some places. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left/lower left.