Stonehenge Formation

Medium-light-gray to medium-gray, finely crystalline, thick-bedded limestone, containing dark siliceous laminae, edgewise conglomerate beds, and fossil-fragment lenses; dolomite beds increase in number eastward.
State Pennsylvania
Name Stonehenge Formation
Geologic age Ordovician
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone (Bed)medium-light-gray to medium-gray, finely crystalline, thickbedded limestone, containing dark siliceous laminae, and fossil-fragment lenses
Minor
Sedimentary > Carbonate > Dolostone (Bed)medium-light-gray to medium-gray, finely crystalline, thickbedded limestone, containing dark siliceous laminae; dolomite beds increase in number eastward.
Incidental
Sedimentary > Clastic > Conglomerate (Bed)edgewise conglomerate beds
References

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.

NGMDB product
Counties Berks - Lehigh