This area--known as the Deuteronilus contact of the Isidis Basin-- has been interpreted as a possible ancient shoreline.
This observation shows a partially-filled impact crater with sediment flow that has breached the south rim.
While most craters on Mars are generated by impacts of asteroids and comets, another process might have been at play here.
The flanks of Tharsis Tholus are cut by large channels, similar to those visible on other Martian shield volcanos like Arsia Mons and Elysium Mons.
Information about the Mars Reconnaissance Orbiter is online at http://www.nasa.gov/mro
. The mission is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, for the NASA Science Mission Directorate, Washington, D.C. Lockheed Martin Space Systems, of Denver, is the prime contractor and built the spacecraft. HiRISE is operated by the University of Arizona. Ball Aerospace and Technologies Corp., of Boulder, Colo., built the HiRISE instrument.
Please follow SpaceRef on Twitter and Like us on Facebook.