Virginia Formation

Slate and graywacke with thin carbonate layers.
State Minnesota
Name Virginia Formation
Geologic age Paleoproterozoic
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > Slate
Sedimentary > Clastic > Sandstone > Graywacke (Bed)
Minor
Sedimentary > Carbonate (Bed)thin carbonate layers
Comments Part of the Animikie Group. Part of the Geon 18 intrusions and supracrustal rocks (syn- to late Penokean orogenesis).
References

Jirsa, Mark A., Boerboom, Terrence J., Chandler, Val W., Mossler, John H., Runkel, Anthony C., and Setterholm, Dale R., 2011, S-21 Geologic Map of Minnesota-Bedrock Geology; Minnesota Geological Survey, State Map Series S-21. Scale 1:500,000.

NGMDB product
Counties Aitkin - Cass - Crow Wing - Itasca