Metamorphic > Metasedimentary > Metaclastic > ArgilliteDark-gray to black, thick-bedded argillite.
Sedimentary > Carbonate > Limestone (Bed)Locally has thin layers of impure limestone and calcareous shale.
Sedimentary > Clastic > Mudstone > Shale (Bed, Calcareous)Locally has thin layers of impure limestone and calcareous shale.
Sedimentary > Clastic > Mudstone > Shale > Black-shale (Bed)Dark-gray to black, thick-bedded argillite containing a few zones of thin-bedded black shale.
Berg, T.M., Edmunds, W.E., Geyer, A.R., and others, compilers, 1980, Geologic map of Pennsylvania: Pennsylvania Geological Survey, 4th ser., Map 1, 2nd ed., 3 sheets, scale 1:250,000.
Pennsylvania Bureau of Topographic and Geologic Survey, Department of Conservation and Natural Resources, Miles, C.E., and Whitfield, T.G., compilers, 2001, Bedrock Geology of Pennsylvania, edition: 1.0, digital map, scale 1:250,000.
|Counties||Berks - Bucks - Chester - Montgomery|