Polygenetic Melange

Pebbles, cobbles, and boulders of granite, gabbro, amphibolite, biotite gneiss, and quartzite in a poly-deformed, mylonitic, schistose metagraywacke matrix. Includes interbedded garnetiferous meta-argillite, feldspathic metagraywacke conglomerate, and meta-arkose. Mineralogy (matrix): quartz + plagioclase + biotite + epidote + apatite + titanite + muscovite ± garnet ± allanite. This unit was named the Ca Ira melange by Marr (1991).
State Virginia
Name Polygenetic Melange
Geologic age Proterozoic
Lithologic constituents
Tectonite > Melange
Comments Central Piedmont

Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia: Virginia Division of Mineral Resources, scale 1:500,000.

Virginia Division of Mineral Resources, 2003, Digital Representation of the 1993 Geologic Map of Virginia, Publication 174, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, scale 1:500,000.

NGMDB product
Counties Cumberland