THEMIS Image of the Day, July 27, 2018. This VIS image is located near Zephyria Planum. Winds of two different directions have excavated a poorly cemented surface into linear ridge features called yardangs.
Examining the structure of the ridges, it appears that winds first blew from the upper left of the image. Then perhaps after a change in climate, winds blew toward the upper right, carving a new pattern on top of the older one. The ridges are not perpendicular, but intersect at a wider angle.