A south-facing escarpment in the Northwest Hellas region that was targeted for the phyllosilicates shows instances of bluish rock in this enhanced color image.
CRISM spectra of the bluish material shows that it consists of a combination of chlorite and water ice. The image was captured at the beginning of southern spring, at a time period when south-facing escarpments still retain ices deposited during the winter.
HiRISE is one of six instruments on NASA's Mars Reconnaissance Orbiter. The University of Arizona, Tucson, operates the orbiter's HiRISE camera, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for the NASA Science Mission Directorate, Washington.