The linear wall at the bottom of this image from NASA 2001 Mars Odyssey spacecraft is a fault. The linear depression caused by faulting is part of a long depression called Mangala Fossae. Orbit Number: 58979 Latitude: -17.9823 Longitude: 210.806 Instrument: VIS Captured: 2015-04-01 00:54 http://photojournal.jpl.nasa.gov/catalog/PIA19468