This image shows three examples of ventifacts from Antarctica (courtesy of T. Cerling) that display flat bottoms, and faceted sides blasted by the wind. The polished surface age is dated at about 2 million years. The center one had amygdules in the volcanic rock that were preferentially eroded and scoured out to leave deep pits.
Originally uploaded in Mars for Earthlings:Lesson Modules.
Image 39280 is a 2550 by 3490 pixel JPEG
Uploaded: Apr9 13