Scoop marks in the sand at 'Rocknest'

The third and fourth trenches dug by NASA's Mars rover Curiosity during soil sampling are seen here in an image captured by the Mars Hand Lens Imager (MAHLI) on October 31. The upper surface of the drift is covered by coarse sand grains approximately 0.02 to 0.06 inches in size which form a thin crust about 0.2 inches (0.5 centimeters) thick.

Beneath the thin crusted surface is finer sand, which is darker brown as compared with the dust on the surface.