The Cimarron River in north-central Oklahoma shows characteristics intermediate between typical braided and meandering streams. In the Perkins area, the gradient is 1.8 ft per mi; the sinuosity is 1.5; and average channel depth at bankfull stage is 15 ft. Accretion ridges on the downstream sides of bars characterize the straighter reaches, whereas accretion ridges on both the upstream and downstream sides are in the more sinuous reaches.

The deposits show upward fining; they are generally fine- to medium-grained, well-sorted sand, with scattered quartz and intraformational pebbles. Horizontal bedding and medium-scale and small-scale crossbedding are the dominant sedimentary structures. Crossbedding, parting lineation, and grain orientation define the sand trend and indicate that directional features of this type are useful in estimating reservoir trend.

Compared to typical meandering-stream deposits, the Cimarron River deposits are thinner but possibly wider, and they contain less fine-grained clastics in the upper part of the sequence and as clay interbeds. The Cimarron sediments are finer grained and better sorted than sands of typical braided streams. They contain more horizontal bedding than either braided- or meandering-stream deposits. The type of sand deposit represented by the Cimarron River sand may be similar to certain ancient alluvial sandstones which were deposited during either basinal subsidence or eustatic rise in sea level.

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