Quartzite and Quartz-Sericite Tectonite (VAYq;0)

State	Virginia
Name	Quartzite and Quartz-Sericite Tectonite
Geologic age	Proterozoic Y
Original map label	Yq
Comments	Blue Ridge Basement Complex, Middle Proterozoic (Early or Pre-Grenville-Age) Gneisses. From expanded explanation (ref. VA002): Quartzite and quartz-sericite tectonite. Light-gray to white, fine- to medium-grained, massive; contains rounded zircons, thin lenses of graphite, and pods of paragneiss (Yp); unit is considered part of a metasedimentary suite.
Primary rock type	quartzite
Secondary rock type	tectonite
Other rock types
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > Quartzite Minor Tectonite
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	Loudoun