Lineated Biotite Granite Gneiss (VAlgn;0)

State	Virginia
Name	Lineated Biotite Granite Gneiss
Geologic age	Proterozoic
Original map label	lgn
Comments	Central Virginia Volcanic-Plutonic Belt From expanded explanation (ref. VA002): Lineated biotite granite gneiss. Dominantly leucocratic to mesocratic, medium- to coarse-grained, strongly-lineated granite gneiss; includes porphyritic granite gneiss. Mineralogy: quartz + potassium feldspar + plagioclase + biotite + muscovite +/- garnet. Geophysical signature: western portion coincides with strong positive radiometric anomaly. This unit likely includes more than one intrusive body; portions may be derivative of felsic volcanogenic rocks. These rocks intrude and are interlayered with metavolcanic rocks of probable Cambrian age. The unit includes granite gneiss of Nelson (1992), and may be correlative in part with the Shelton Formation (Ost).
Primary rock type	granitic gneiss
Secondary rock type
Other rock types
Lithologic constituents	Major Metamorphic > Gneissgranitic gneiss
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	Appomattox - Campbell - Charlotte - Halifax