(15) Stratigraphy and facies analysis of the lower Pennsylvanian Raccoon Mountain formation at Cascade Falls and Coolie's Rift, Southern Cumberland Plateau, Monteagle, Tennessee

The study area is located on the southern Cumberland Plateau near Monteagle, Tennessee. Here, three stratigraphic sections of the Morrowan Raccoon Mountain Formation demonstrate significant variation, especially in their lower... [ view full abstract ]

The study area is located on the southern Cumberland Plateau near Monteagle, Tennessee. Here, three stratigraphic sections of the Morrowan Raccoon Mountain Formation demonstrate significant variation, especially in their lower portions. Much of the variation is related to 2-3 m of relief on the underlying disconformity, which has been previously linked to a eustatic sea level drop. Fluvial conglomerates or underclay below the bituminous Bon Air Coal mark the base of the unit in more deeply incised areas, while cross bedded channel sands lie immediately above the unconformity in paleo- uplands. The disconformity itself is characterized by a deeply oxidized (paleosol?) zone 1-8 cm thick, suggesting a significant weathering period prior to the deposition of Pennsylvanian strata. A facies analysis of the unit suggests fluvial deposition within the context of a near-shore, deltaic environment. The Raccoon Mountain forms the lowest member of the Gizzard Group; it is unconformably underlain by the Mississippian Pennington Formation and uncomformably overlain by the Warren Point Sandstone, which forms a large overhang near Cascade Falls along Trussell Creek.