Tectonic fractures within the Candor Chasma region of Valles Marineris, Mars, retain ridge-like shapes as the surrounding bedrock erodes away. This points to past episodes of fluid alteration along the fractures and reveals clues into past fluid flow and geochemical conditions below the surface.

The High Resolution Imaging Science Experiment camera on NASA's Mars Reconnaissance Orbiter took this image on Dec. 2, 2006. The image is approximately 1 kilometer (0.6 mile) across. Illumination from the upper left.

This view is a portion of the camera's image catalogued as PSP_001641_1735. A full resolution file of this image is available for download by clicking here (69 MB).

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo.