Without plants, the stable hills of sand people recognize as dunes would not form. “It would be like the very open, shifting sand environment that you see on Arrakis,” Hacker said.

Now scientists have discovered that a dune called Lala Lallia in Morocco formed 13,000 years ago ... is located in the Erg Chebbi sand sea in south-east Morocco. It is 100m high and 700m wide ...

Scientists have solved the mysterious absence of star-shaped dunes from Earth's geological history for the first time, dating one back thousands of years. The study by Aberystwyth University ...

Perched sand dunes are formed by a very specific geologic process, according to the National Parks Service. Glaciers leave behind large bluffs of rocks, sand, and other debris, hundreds of feet high.