
The winds in this part of Mars blow predominantly from the west (top), pushing and moving sand around to form these distinctive wave crests. The sand itself is fine and basaltic in nature – meaning that it’s rich in minerals such as pyroxene and olivine, which are formed by volcanoes – and is constantly in motion, causing these dynamic landforms to slowly change and evolve over time.
There are also signs of water-related activity here. Martian winds have stripped away the upper layers of the planet’s surface in places, revealing light-toned clay rock that likely formed in the presence of water. There are also little gullies and narrow channels lining the steeper walls of some of the craters here – while these were likely formed by dry landslides slipping down unstable slopes, some of the older gullies may have formed as ice reserves melted, or buried groundwater reservoirs caused the ground above to shift.