Quartz Gabbro and Quartz Diorite Gneiss

Mixed rock zone of greenish-black, uralitized, quartz-bearing gabbro to dark gray, weakly gneissic, pyroxene-hornblende-biotite quartz diorite.
State Maryland
Name Quartz Gabbro and Quartz Diorite Gneiss
Geologic age Paleozoic
Lithologic constituents
Major
Igneous > Plutonic > Dioritic > Quartz-diorite
Igneous > Plutonic > Gabbroic > Gabbro
References

Cleaves, E.T., Edwards, J., Jr., and Glaser, J.D., 1968, Geologic Map of Maryland: Maryland Geological Survey, Baltimore, Maryland, scale 1:250,000.

In 1995 the Water Resources Division of the U.S. Geological Survey digitized the geologic map of Maryland from the 1968 paper map (Reference MD001). Information about products from the Maryland Geological Survey can be found at http://www.mgs.md.gov/.

NGMDB product
Counties Harford