moving wind or water
Sand dunes are a collection of sand caused by eroding sandstone, formed by wind and waves. The sand is blown up against dune grass and rocks where it starts to accumulate into dunes – the grass is their basis, and without it the dunes probably wouldn’t exist.
There are plenty of sand dunes that have nothing to do with grass, including those on Mars – http://mars.jpl.nasa.gov/gallery/sanddunes/PIA03740.html
Click here to cancel reply.
Sorry,At this time user registration is disabled. We will open registration soon!
Don't have an account? Click Here to Signup
© Copyright GreenAnswers.com LLC