Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Entire DC Network
Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand
Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand
Masters Theses
The rise and demise of mountain belts, caused by growth, modification, or removal of the continental lithosphere are fundamental processes that influence almost all Earth systems. Understanding the nature, timing, and significance of active processes in the creation and evolution of modern mountain belts is challenged by a lack of middle crustal and lower crustal exposures. Analogues can be found in ancient orogens, whose deeply eroded roots offer a window into deeper processes, yet this record is complicated by overprinting events and complex deformational histories. Research presented herein constrains the tectonic history of multistage Appalachian Orogen, type locality of the …
Late Tertiary Tectonic Uplift In The Southern And Central Appalachians, Mary Sheela Biswal
Late Tertiary Tectonic Uplift In The Southern And Central Appalachians, Mary Sheela Biswal
Masters Theses
The exposed Appalachian Mountains extend about 2500 km from Newfoundland to Alabama with the highest peaks >2000 m above sea level. The last orogeny that affected Appalachian crust was the 325-260 Ma Alleghanian. Even with minimal erosion rates, it is highly unlikely that the Appalachians could have sustained such elevations for over 200 m.y., suggesting that recent tectonic uplift has produced today’s mountainous topography. The multiple phases of Tertiary uplift are related to poorly understood processes, but a large amount of data from today’s mountain chain and the adjacent Coastal Plain indicate the present high topography is anomalous and clearly …
Metamorphism, Kinematic Evolution, And Timing Constraints Of The Greenbrier Fault Around The Ela And Bryson City Domes, North Carolina, Remington M. Leger
Metamorphism, Kinematic Evolution, And Timing Constraints Of The Greenbrier Fault Around The Ela And Bryson City Domes, North Carolina, Remington M. Leger
Masters Theses
Field mapping, microstructural analysis, and electron microprobe analysis were performed on rocks from the Bryson City and Ela domes, North Carolina, to help constrain the tectonic history of the region. The domes are en echelon northeast-trending antiformal structures formed by two perpendicular sets of folds. They are bounded by the Greenbrier fault, which forms a ductile shear zone that juxtaposes the Great Smoky Group in the hanging wall with Grenville basement in the footwall. Isoclinal folds (F2) and axial planar foliation (S2) characterize the regional deformation (D2). Inter- to syn-kinematic porphyroblasts (relative to D2) of kyanite, staurolite, and garnet grew …