Spiders on Mounds
Jet Propulsion Laboratory https://www.jpl.nasa.gov/ Dec. 21, 2016
This terrain looks like lumpy sediment on top of patterned ground. The lumpy sediment is likely just loosely consolidated because it is covered with spidery channels.
This landform is uniquely Martian, formed in the spring as seasonal dry ice turns directly into gas that erodes channels in the surface.
The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.