This image lies within the Deuteronilus Mensae region, located on the northern edge of Arabia Terra and borders the high-standing, heavily cratered Southern Hemisphere and the low, relatively uncratered, plains of the Northern Hemisphere of Mars.

Deuteronilus Mensae is characterized by hills and mesas surrounded by broad debris aprons and this HiRISE image shows examples where lobate-shaped debris aprons appear to overlap.

There is zone of ridges that formed in an area where lobate debris aprons merged from different directions. A current hypothesis is that these ridges are expressions of compressional deformation between two lobes acting like a viscous fluid. One possibility, given the high latitude of the occurrence, is that the lobes of debris are ice-rich and flow somewhat like glaciers.

Recent results from the SHAllow RADar (SHARAD) instrument, also onboard the Mars Reconnaissance Orbiter, indicate that lobate debris aprons in Deuteronilus Mensae are composed of material dominated by ice (Plaut et al., 2008). This supports the interpretation that these might be potential debris-covered glaciers or rock glaciers.

Some of the detailed textures on the surface of the debris aprons are commonly believed to be the result of ice loss due to sublimation (ice changing into water vapor). On Earth, debris-covered glaciers/rock glaciers typically develop wrinkles and fractures due to stresses in the ice as it flows. Where flows merge, they can buckle and push up ridges producing features similar to those visible here.

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.