Structural Geology of the Eastern Limb of the Blue Ridge Anticlinorium, in the Schuyler area, central Virginia
The Schuyler 7.5’ quadrangle is located approximately 30 km south-southwest of Charlottesville, Virginia on the eastern limb of the Blue Ridge Anticlinorium. Within this region lies a profound geologic boundary between billion-year old basement rock and a significantly younger suite of Neoproterozoic rock previously defined as the Lynchburg Group. This contact has been interpreted as a fault or an unconformity. To test these models I mapped the northeast corner of the Schuyler 7.5’ quadrangle. The bedrock geology consists of the Grenvillian basement complex that is overlain by a cover sequence of metasedimentary and metavolcanic units that includes Neoproterozoic rocks of the Lynchburg Group and Catoctin Formation, as well as the early Cambrian Evington Group. The basement complex, exposed in the northwest corner of the quadrangle, consists of Grenvillian granitoid and gneiss that is intruded by two Cyrogenian A-type plutons and their associated dikes. The basement complex is unconformably overlain by a >6 km thick cover sequence. The Lynchburg Group is primarily an arkosic sequence derived from erosion of the basement complex. We revise the stratigraphy of the Lynchburg Group and recognize five formations, many of which are bound by significant unconformities. A mafic-ultramafic complex, metamorphosed to metagabbro and soapstone/serpentinite, intrudes the basement complex and the Lynchburg Group. The evidence suggests that the contact between basement and the Lynchburg Group is certainly a massive unconformity, and that in some parts the older basement rock lies atop the overturned cover rock.
Cullen, Katie, "Structural Geology of the Eastern Limb of the Blue Ridge Anticlinorium, in the Schuyler area, central Virginia" (2022). Geology Senior Theses. William & Mary. Paper 23.