Lynchburg Group; Charlottesville Formation (VAZch;0)

State	Virginia
Name	Lynchburg Group; Charlottesville Formation
Geologic age	Proterozoic Z
Original map label	Zch
Comments	Lynchburg Group; Blue Ridge Anticlinorium, Central. From expanded explanation (ref. VA002): Charlottesville Formation (Nelson, 1962). Coarse-grained to pebbly quartzose metasandstone and quartzite interbedded with laminated micaceous metasiltstone and graphitic phyllite and slate. Sandstone beds are typically amalgamated and massive; grading, horizontal stratification, and complete Bouma sequences are preserved locally (Wehr, 1985; Conley, 1989). The formation includes cross-bedded quartzite, feldspathic metasandstone, and muscovite schist in the upper portion (Conley, 1989; mapped as Swift Run Formation by Nelson, 1962); in the Culpeper area, includes in part the Ball Mountain Formation of Wehr (1985) and Kasselas (1993). The unit contains numerous apparently concordant mafic and ultramafic sills in the lower portion. Southwest of Nelson County, rocks equivalent to the Charlottesville Formation have been mapped as Alligator Back Formation. Outcrop belt is as much as 3.7 miles wide.
Primary rock type	meta-argillite
Secondary rock type	sandstone
Other rock types	quartzite; phyllite; slate
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > Argillitemeta-argillite Minor Metamorphic > Metasedimentary > Metaclastic > Metasandstonemeta-argillite Metamorphic > Metasedimentary > Metaclastic > Quartzite Metamorphic > Metasedimentary > Metaclastic > Metasiltstonemeta-argillite Incidental Metamorphic > Metasedimentary > Metaclastic > Slate Metamorphic > Metasedimentary > Metaclastic > Phyllite
Map references	Digital Representation of the 1993 Geologic Map of Virginia", 2003, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, viewing software not included. This is a digital version of "Geologic Map of Virginia" published in 1993. Available from: https://www.dmme.virginia.gov/commerce/ [https://www.dmme.virginia.gov/commerce/]
Unit references	Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia: Virginia Division of Mineral Resources, scale 1:500,000 Digital Representation of the 1993 Geologic Map of Virginia - expanded explanation: 2003, Commonwealth of Virginia, Department of Mines, Minerals, and Energy, Divsion of Mineral Resources, Publication 147, 85 pp Digital Representation of the 1993 Geologic Map of Virginia", 2003, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, viewing software not included. This is a digital version of "Geologic Map of Virginia" published in 1993. Available from: https://www.dmme.virginia.gov/commerce/ [https://www.dmme.virginia.gov/commerce/]
Geographic coverage	Albemarle - Culpeper - Fauquier - Madison - Nelson - Orange - Charlottesville