Little Sahara State Park - Waynoka, OK
Posted by: 
The Snowdog
N 36° 32.215 W 096° 52.655
14S E 689996 N 4045598
Sand Dunes in Oklahoma? Little Sahara State Park is centered on this geologic oddity - south of Waynoka, Oklahoma.
Waymark Code: WM160AJ
Location: Oklahoma, United States
Date Posted: 04/06/2022
Views: 1
Little Sahara is centered on a geologic oddity - a field of sand dunes, not seen anywhere else in Oklahoma, that formed over time from terrace deposits left long ago when the Cimarron River flowed over the entire area. Originally deemed a nuisance (Highway 281 has been re-routed to the east three times due to the northeast migration of the dunes), the State purchased the land after it had proved popular with locals who constructed home-made "dune buggies" to traverse the dunes. The park now contains a thousand acres of razorback dunes and is a popular destination for hiking, camping, and motorized excitement. There is no fee to access the dunes; permits are required for overnight or extended camping.
In geology, a "terrace" is a step-like landform consisting of a flat (or nearly flat) surface that is bound on one side by a steep ascending slope. One way that terraces can form is by the downcutting of a river into a floodplain, and (after the waters have receded) the erosion of that former floodplain. The terrace deposits that created Little Sahara were left during the Pleistocene when wide, shallow rivers (the remnant of which is the Cimarron River) flowed across what is now northwest Oklahoma and deposited vast amounts of sand in the river floodplain. After millennia of erosion these sand deposits are now exposed. The dunes are created by the prevailing south and southwest winds, which pushes sand up the gentle windward side of the dunes and down the steep lee side to create "razorback" dunes. The dunes are slowly migrating to the northeast. The typical depth of the sand in the park is between twenty-five and seventy-five feet.
Sources:
Wikipedia: Terrace
Oklahoma Historical Society