This image shows the distal end of a set of braided channels west of Hecates Tholus. Hecates Tholus, a volcano, is located in the northern hemisphere of Mars and is the northernmost of three volcanoes within Elysium Planitia.

The Elysium volcanoes are believed to have experienced a more diverse volcanic history than that of the Tharsis volcanoes. In addition to numerous lava flow units, several observed channels have been interpreted as both volcanic and fluvial in origin.

The braided channels in this image appear to have carved into young lava flows. Like braided rivers on Earth, they consist of a network of small channels, often separated by small streamlined islands. The morphology of the channels and the fact that they are braided and have streamlined islands has led to interpretations of a fluvial rather than a volcanic origin. Although the channels are heavily mantled by fine sediments, some appear to vary in depth. This, along with the presence of multiple channels, suggests that they may represent more than one episode of fluvial activity.

The water that potentially formed the braided channels may have been released due to igneous intrusions into ground ice or to the emplacement of lava flows on ice-rich terrain. Altogether, morphologies and landforms in the surrounding area indicate extensive volcano-ground ice interactions in the past.


Written by: Maria Banks

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.