GEOLOGY OF THE 1:24,000 ROANOKE EAST, ALABAMA, QUADRANGLE: IMPLICATIONS FOR THE TECTONIC EVOLUTION OF THE SOUTHERNMOST APPALACHIANS

The 1:24,000 Roanoke East, Alabama, Quadrangle is located in the Piedmont province of the southern Appalachians in east-central Alabama, and encompasses rocks from two major terranes, the eastern Blue Ridge (EBR) and the Inner Piedmont (IP), that are separated by the Brevard zone (BZ). As a whole, the Piedmont includes metasedimentary, metavolcanic, and metaplutonic rocks that formed as a result of processes associated with the Taconic (Ordovician), Acadian-Neoacadian (Devonian-Mississippian), and Alleghanian (Carboniferous) orogenic events. Over the years, several different hypotheses have been proposed regarding the relationship between the Emuckfaw (EBR) and Jacksons Gap (BZ) Groups, as well as their potential correlation to the rocks of the Opelika Complex on the southeastern margin of the Dadeville Complex (IP) and eastern limb of the Tallassee synform. Geologic mapping of the Roanoke East Quadrangle was conducted as part of a master’s thesis, the objectives of which include: (1) to map and describe the lithologies, fabrics, and structures in rocks underlying the Roanoke East Quadrangle; (2) to characterize the mineral assemblages and microstructures of rocks in the study area; (3) to compile all data into a digital geologic map of the quadrangle; (4) to conduct thermobarometric analyses on select rock samples from the Emuckfaw and Jacksons Gap Groups; and, (5) to synthesize all results and data to help further understand the tectonic evolution of the southernmost Appalachians. While the thermobarometric analyses are still in progress, the geologic mapping has been completed and has contributed significantly to the understanding of the problems addressed by this study.