SYNDEPOSITIONAL SLOPE INSTABILITY WITHIN OCOEE SUPERGROUP EXPOSURES ALONG THE HIAWASSEE RIVER, CHEROKEE NATIONAL FOREST, TENNESSEE

The northeast-trending railroad cut parallel to the Hiawassee River exposes metamorphosed Ocoee Supergroup rocks. Much controversy exists over the ages of the formations, the nature of contacts, the degree of metamorphism, and the depositional environments of protoliths. The Geologic map of Tennessee indicates that most of it belongs to the Walden Creek Group and is metamorphosed to the chlorite grade. Hatcher (2012) indicates that most of it belongs to the Precambrian Wilhite Formation which conformably overlies the Dean Formation. Tull (2012) indicate that most of it belongs to a Paleozoic Wilhite Formation that unconformably overlies the Precambrian Dean Formation, and may have undergone biotite grade metamorphism.

The exposures proximal to the confluence of Wolf Creek and the Hiwassee considered in this study offer new insight into this controversy. Field examination, microscopic study, and X-ray analysis indicate that the rocks have been subjected to the chlorite grade of the greenschist facies metamorphism that preserved relict textures and structure though no fossils were observed. Here, the rock is abundantly crossbedded. Strata are generally interbedded into fining upward sequences. Different depositional slope of bed sets, rotated crossbeds, slump structures and intraformational folds indicate the strata may have been deposited on a tectonically active margin. By assuming that foliations are axial planar, and the structural data measured from selected outcrops of non-overturned beds had a uniform depositional surface, flow direction at time of sedimentary deposition was estimated by standard stereonet methods. Two dominant directions of paleocurrent are determined. Field observation indicates that the paleoflow of older strata is dominantly to south, and younger strata are to the north.