The steep sided depressions in this image captured by NASA 2001 Mars Odyssey spacecraft are fault bounded tectonic features called graben. These depressions are part of a large region of graben called Sacra Fossae. Sacra Fossae is located on the western margin of Lunae Planum. Orbit Number: 60829 Latitude: 18.2961 Longitude: 287.711 Instrument: VIS Captured: 2015-08-31 10:01 http://photojournal.jpl.nasa.gov/catalog/PIA20094