SAND DUNES

Sand dunes form some of the most spectacular and dynamic landforms on the planet. A sand dune is a mount, hill or ridge of sand that lies behind the part of the beach affected by tides. A sand dune is not a permanent structure.

How is it formed?

Wind carries fine grains of sand and bounces heavier sand grains along. And while the wind isn't strong enough to move really heavy grains of sand, bouncing sand is enough to push the heaviest grains forward. Finally, an obstacle, such as a plant or rock, is needed to block the wind and cause the sand to pile up. Once sand piles up dunes can form.

Interesting Facts

A sand dune is a mount, hill or ridge of sand that lies behind the part of the beach affected by tides.

They are formed over many years when windblown sand is trapped by beach grass or other stationary objects.

Sand dunes support an array of organisms by providing nesting habitat for coastal bird species including migratory birds.

Examples

Buttercup sand dune Olancho dunes Kermit sand dunes Syracuse sand dune park St. Anthony sand dunes

Not actual images

Recourses sihttp://des.nh.gov/organization/commis

oner/pip/factsheets/cp/documents/cp-02.pdf members.virtualtourist.com off-roadweb.com humanandnatural.com http://des.nh.gov/organization/commissioner/pip/

factsheets/cp/documents/cp-02.pdf http://www.duneguide.com/sand_dune_guide_kermit.htm humanandnatural.com http://toptravellists.net/sunrise-sand-dunes-namibia.html bpham.com