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Chesapeake Group; St. Marys Formation

Chesapeake Group; St. Marys Formation - Greenish-blue to yellowish-gray sandy clay and fine-grained argillaceous sand; thickness 0 to 80 feet.
State Maryland
Name Chesapeake Group; St. Marys Formation
Geologic age Miocene
Primary rock type clay or mud
Secondary rock type sand
Other rock types
Lithologic constituents
Major
Unconsolidated > Fine-detrital > Clay
Unconsolidated > Coarse-detrital > Sand
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Unpublished digital version of the Maryland state geologic map that was digitized by the USGS Water Resources Office in Towson, MD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 Calvert - Saint Mary's