Eolian and Periglacial Activities in Vastitas Borealis (DD Tracks and Polygons)

This image shows a region of approximately 7 x 7 km (4.4-by-4.4 miles) located in Vastitas Borealis, part of the Northern Plains.

The surface imaged is relatively young, as indicated by the lack of recent impact craters.
Eolian and Periglacial activity seem to be the dominant geological processes at work, as shown by numerous crisscrossing DD Tracks and ubiquitous polygonal features, respectively.

Dust Devils form when the sun warms up the air near a flat, dry surface. Warm air then rises quickly through the cooler air above and starts spinning, causing a forward motion. The spinning, forward-moving cell may pick up dust and sand as it advances, thus leaving behind a "clean" track. We infer from this image that a thin veneer of light-colored particles of dust and/or fine-grained sand cover relatively darker materials, apparent in the dust devil tracks.

The tracks pictured in this image are in many cases more than 30 mt (27 yards) wide and over 4 Km (2,5 miles) long, surpassing the dimensions of average terrestrial DD tracks.