Southeastern Section - 57th Annual Meeting (10–11 April 2008)

Paper No. 11
Presentation Time: 8:00 AM-5:30 PM

DIGITAL GEOLOGIC MAP OF THE PARKSVILLE 7 ½-MINUTE QUADRANGLE, TENNESSEE


JOHN, Nick L., Department of Geological Sciences, Florida State University, 108 Carraway Building, Tallahassee, FL 32306, john@gly.fsu.edu

Geologic mapping of the Parksville 7.5' quadrangle in the southern Appalachians of SE Tennessee was conducted with support from the U.S.G.S under the guidelines of the Educational Mapping Cooperative agreement (EDMAP) between the U.S.G.S, Tennessee Division of Geology, and Florida State University. The Parksville quad was strategically chosen for geological mapping as a continuation of multiple studies and mapping projects situated along the frontal thrust boundary of the southern Appalachian-Blue Ridge. Previous tectonostratigraphic studies of the area, in, and surrounding this map were generally conducted at a more regional scale. Detailed geologic mapping is an essential aid to further address problems associated with the tectonostratigraphic history of these complexly deformed rocks. The Great Smokey thrust is the boundary separating the distinct physiographic and structural terrains of the foreland fold and thrust belt from the western Blue Ridge allochthon. This fault places the Late Proterozoic, low grade metamorphic rocks of the Walden Creek Group and the Early Cambrian Chilhowee Group, found to the east and in the hanging wall, in structural contact above the unmetamorphosed, Early to Middle Ordovician stratigraphy of the Knox Group and Athens Shale to the west and in the footwall of the fault. The map-scale repetition of foreland stratigraphy within the quad results from folding, rather than fault imbrication. The map shows a series of southward plunging map-scale synclines and anticlines, which fold foreland stratigraphy, including the Knox unconformity, which become obliquely truncated southwestward by the overlying Great Smokey fault. The Chilhowee Group is stratigraphically underlain by the thinly bedded sequence of the Sandsuck Formation. Like the above described folds within the foreland, the thrust sheet containing the Chilhowee and Sandsuck is also obliquely truncated southwestward along the frontal thrust as the roof fault (the Maggies Mill fault) of the Chilhowee block merges southwestward with the frontal Blue Ridge thrust. The Maggies Mill fault carries above it a polydeformed and metamorphosed sequence of Wilhite Formation, composed of metaconglomerate, metsasandstone, and laminated phyllite. Northwest vergent, synmetamorphic folds within the Whilhite are doubly plunging shallowly to moderately to the NE and SW.