The 200 metre high sand dunes at Sossusvlei in the Namib Desert in Africa? After the raging floodwaters of Noah's Flood (violent enough to create the Grand Canyon so presumably also destructive of any pre-existing dunes made of desert sand) had receded. Correct? http://commons.wikimedia.org/wiki/File: ... usvlei.JPG
I imagine they'll just deny that they are aolian - ISTR we've seen a bit of that before (maybe on RatSkep, though). "Big floods make big ripples"! ETA: or maybe, like light, wind went faster in those days?
"PPSIMMONS is an amorphous mass of stupid" - Rationalwiki