This image shows the intersection of two overlapping craters, although it is unknown which of the two formed first.
The two craters are covered in a mantling material, which gives them a smooth appearance. The mantling unit is thought to be water ice-rich. Concentric circles are visible on the floor of one crater. It is likely that these circles are evidence of ice-rich material that flowed off the crater wall, driven by gravity, onto the crater floor.
Outside of the craters, the plains have a pitted or dissected texture. Both of these textures are suggestive of material that once held ice that has since disappeared allowing the remaining soil to collapse into the subsurface. There are also dark dust devil tracks across the scene.
Written by: Kelly Kolb (14 May 2008)
More info and image formats at http://hirise.lpl.arizona.edu/PSP_006736_1325
Image: NASA/JPL/University of Arizona