Streams in the Appalachian Plateau

The drainage pattern of the Cumberland Plateau is grossly dendritic (heavily branched) but, various other patterns occur.The latterinclude angulate, rectangular, trellis, radial, and annular patterns, which reflect joint sets, small and large folds, and broad, inconspicuous domes. Linear drainage lines are also locally common.

(Mayfield 1981)reported that mean annual floods of Cumberland Plateau streams are much higher per unit area thanthose ofother Tennessee streams. He attributed this pattern to the low permeability of Plateau bedrock and the high permeability of the thin soils andwhich allow rapid throughflow to stream channels. Base flows are correspondingly low, (and streams arevery likely to run dry in the summer). Streams with highest flood peaks drain areas underlainwith conglomeratie bedrock.

The course of the Tennessee River on the Cumberland Plateau is striking. After flowing in valleys from Virginia to almost the Tennessee-Georgia border, it abruptly cuts westward across the anticlinal Walden Ridge, producing the Tennessee River gorge. After cutting through the ridge, the Tennessee enters the Sequatchie Valley and follows it for about 120 km before abruptly turning northwest again into the Cumberland Plateau, and thence into the Interior Low Plateau, where it eventually turns north and joins the Ohio River. Geomorphologists have argued for more than a century about the possibility that the Tennessee once continued its southwestwardflow fromthe Ridge and Valley province all the way to the Gulf of Mexico, or perhaps that it continued itsflow down the Sequatchie Valley to the Gulf. No definitive evidence has been uncovered, however.