Dunes inside Russel Crater (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)

The Russell Crater Dunefield is covered seasonally by Carbon Dioxide (CO2) Frost, and this image shows the Dunefield after the Frost has sublimated (evaporated directly from solid to gas). There are just a few patches left of the bright seasonal frost.
Numerous dark DD Tracks can be seen meandering across the Dunes. The face of the largest dune is lined with Gullies. The source of the Gullies is unclear but could involve erosion by the seasonal CO2 Ice.