These impact craters in the northern middle latitudes have interesting interiors: all of them have wind-blown (aeolian) ripples.
Outside of the craters and along the crater floors, the ripples are all oriented in the same direction. However, along the walls of some of the larger craters, the ripples are situated radially away from the center, indicating the winds moving inside the larger craters can be influenced by the topography of the crater wall.

Additionally, many of the larger craters have layered mesas along their floors that are likely sedimentary deposits laid down after the craters formed but prior to the development of the aeolian ripples.

The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. (The original image scale is 58.6 centimeters [23.1 inches] per pixel [with 2 x 2 binning]; objects on the order of 176 centimeters [69.3 inches] across are resolved.) North is up.

The University of Arizona, in Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., in Boulder, Colorado. 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.

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