From Laurentia to Iapetus: Traversing the Blue Ridge–Piedmont terrane boundary in central Virginia
Christopher M. Bailey, Anna V. Spears, Aaron Marshall, 2017. "From Laurentia to Iapetus: Traversing the Blue Ridge–Piedmont terrane boundary in central Virginia", From the Blue Ridge to the Beach: Geological Field Excursions across Virginia, Christopher M. Bailey, Shelley Jaye
Download citation file:
The Blue Ridge and Piedmont provinces in the central Virginia Appalachians are underlain by Proterozoic and Paleozoic rocks that record multiple episodes of continental collision and rifting. This trip focuses on rocks and structures formed at the southeastern margin of Laurentia during: (1) the Mesoproterozoic assembly of Rodinia, (2) the Cryogenian to Ediacaran rifting that ultimately created the Iapetus Ocean, and (3) the Paleozoic deformation and metamorphism associated with the closure of the Iapetus Ocean and Appalachian orogenesis. A Neoproterozoic to Early Cambrian cover sequence records the transition from continental rifting to a passive margin, but the character of this sequence is vastly different on the eastern and western limbs of the Blue Ridge anticlinorium, reflecting spatial differences in both the timing and tectonics of the Iapetan rift. Blue Ridge rocks experienced NW-directed contractional deformation during the Neo-Acadian (355-330 Ma), whereas low-grade metasedimentary rocks in the western Piedmont were deformed and cooled prior to ca. 400 Ma. In central Virginia, the boundary between the eastern Blue Ridge and western Piedmont is a 3- to 5-km-wide zone of distributed dextral transpression.
Figures & Tables
From the Blue Ridge to the Beach: Geological Field Excursions across Virginia
This volume includes seven field guides that explore the diverse geology of Virginia from its Appalachian highlands to the Atlantic shore. The guides cover an array of topics ranging from cave and karst development in the Valley and Ridge to the exceptional fossil localities at the Carmel Church Quarry and the cliffs near Stratford Hall to Precambrian rocks in the Blue Ridge Mountains. Three guides focus on the Paleozoic to Proterozoic tectonic history of the Blue Ridge and Piedmont provinces, two guides discuss the stratigraphy and fossil assemblages preserved in Cenozoic deposits on the Atlantic Coastal Plain, one guide examines Paleozoic stratigraphy and cave formation in western Virginia, and the final guide explores the relationship between the geology of the Fall Zone and the Civil War during the Petersburg Campaign in 1864–1865.