This image shows an area of layered deposits in Candor Chasma. Here, sheets and dunes of dark-toned sand cover the light-toned, layered bedrock. Accumulations of dark sand accentuate bedding within the light-toned bedrock, giving some areas a zebra striped pattern.

In the northern part of the scene, the bedrock has been eroded into steep, craggy cliffs. Some sections of these cliffs are covered by triangular-shaped debris fans that are intermediate in color between the dark-toned sand and light-toned bedrock.These fans may contain a mix of light-toned bedrock that has crumbled away from the surrounding cliffs and wind-blown sand and dust.

The surfaces of some fans are dissected by gullies, which most likely formed through dry avalanching. The bottoms of the gully channels are often darker in tone than the surrounding fan surface. This may be due to accumulations of wind-blown sand in the gully floor. The subimage shows a clear example of a gullied fan from the northern portion of the scene.
Written by: ChrisO

All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible: Image: NASA/JPL/University of Arizona

For information about NASA and agency programs on the Web, visit: http://www.nasa.gov. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems is the prime contractor for the project and built the spacecraft. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona. The image data were processed using the U.S. Geological Survey’s ISIS3 software.