The Middle Ordovician Tellico-Sevier syncline: A stratigraphic, structural, and paleoseismic investigation

Analyses of remote-sensing satellite data, aerial photography, radar images, and digital elevation models, and detailed (1:24,000-scale) geologic mapping of bedrock and surficial deposits were conducted in a portion of the southeastern Tennessee. This area contains the southern portion of the Tellico-Sevier Alleghanian syncline and the highest concentration of modern earthquakes. Cambrian to Mississippian age rocks occur in the syncline.; Earthquakes occur in the East Tennessee seismic zone (ETSZ) with greater frequency than anywhere east of the Rocky Mountains outside of the New Madrid seismic zone and the Charlevoix region in Canada. No earthquakes greater than M = 4.9 have been recorded in the ETSZ, although the observation window of historical seismic activity is narrow. It is possible that large earthquakes have occurred in the past. The identification of two sites in or near the modern ETSZ with anomalous and potentially earthquake-related deformed Quaternary sediments underscores the need for continued study to properly assess the seismic hazard of this zone.; A new stratigraphic column has been developed for the southern portion of the Tellico-Sevier syncline in sufficient detail to separate potential Quaternary paleoseimic features from both Alleghanian deformation and depositional-related features such as paleosinkholes or facies changes. The stratigraphic column also unifies the previously terminology for Paleozoic units. This column uses established rock unit names that, although they do not conform to current state geologic map terminology, more accurately represent the rocks present in the southern portion of the Tellico-Sevier syncline. The Chapman Ridge Sandstone was studied in particular detail. It has never been mapped as a discrete unit over such a large area; so only a few 1:24,000-scale geologic maps separate it from the Holston Formation. Facies and unit thicknesses in the Chapman Ridge vary across and along its outcrop belt. It is less cross bedded, less ferruginous, and thinner to the south. Cross-bed orientation measurements were collected at over 50 stations between Tennga, Georgia, and Mascot, Tennessee, to determine paleocurrent vectors to investigate paleodispersal. These data reflect a weak though discernable pattern of regional current directions (south-southeast) and sediment dispersal.*; *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Adobe Acrobat.