Gigas Sulci

A sulcus (or sulci, plural) is defined as "subparallel furrows and ridges." This is a purely descriptive term for landforms that could have a variety of origins.

At this location is appears to be a graben (which is a fault-bounded valley) on a large scale, and locally (such as in this image) became a vent region for lava flows.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.