HiRISE: Yardangs forming near Gordii Dorsum

The purpose of this observation is to determine how these formations, called “yardangs” are forming within a layer of bedrock. Yardangs are streamlined hills that are carved by wind erosion from bedrock. The rock must be sufficiently erodible for wind to either deflate (pick up) poorly-consolidated pieces or scrape the surface by blowing sand….. [More at link]