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Pamunkey Group; Nanjemoy Formation

Pamunkey Group; Nanjemoy Formation - Dark green to gray, argillaceous, glauconitic, fine- to medium-grained sand; minor gray to pale brown clay; total thickness 0 to 125 feet; Marlboro Clay member at base: Pink to gray, homogeneous plastic clay with local lenses of very fine-grained white sand; thickness 0 to 30 feet; present west of Chesapeake Bay only; total thickness 0 to 125 feet.
State Maryland
Name Pamunkey Group; Nanjemoy Formation
Geologic age Eocene
Primary rock type sand
Secondary rock type clay or mud
Other rock types
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand
Minor
Unconsolidated > Fine-detrital > Clay
Map references
Cleaves, E.T., Edwards, J., Jr., Glaser, J.D., 1968, Geologic Map of Maryland: Maryland Geological Survey, Baltimore, Maryland, scale 1:250,000.
Unit references
Cleaves, E.T., Edwards, J., Jr., Glaser, J.D., 1968, Geologic Map of Maryland: Maryland Geological Survey, Baltimore, Maryland, scale 1:250,000.
Unpublished digital version of the Maryland state geologic map that was digitized by the USGS Water Resources Office in Towson, MD
Counties Anne Arundel - Charles - Prince George's