Compositional Sorting of Topographically High Tennessee River Gravels: A Glacial Hypothesis

Compositional sorting of topographically high river terrace gravels along the southwestern portion of the Tennessee River valley may be explained by alternate blanketing and uncovering of the source of metaquartzite by glacial ice in the Blue Ridge province of the southern Appalachians. Glacial meltwater may have caused the Tennessee River to spill over into the Black Belt of Mississippi where metaquartzite cobbles are found associated with a Rancholabrean vertebrate fauna. Heavy minerals associated with the metaquartzite cobbles are similar on both sides of the present Tennessee Valley Divide, adding support for a glacially controlled temporary spillover of the Tennessee River.