Understanding the Great Sand Dunes System: the Sand Sheet

The sand sheet is a sandy grassland that forms a vital part of the Great Sand Dunes geological system, lying between the dunefield and the sabkha. Its deepest portions may be remnants of an ancient lake system, while its surface is made of wind-blown sand gradually moving toward the dunefield from lakes in the sabkha. The Great Sand Dunes form where multi-directional winds push sand grains into the tallest dunes in North America. Today grasses, flowers, and shrubs generally stabilize the sand sheet’s surface, though occasional disturbances allow small dunes to form and migrate toward the dunefield. The sand sheet grasslands support pronghorn, elk, burrowing owls, and many other prairie and desert species.

Colorado · United States