Stonehenge/Larke Formation

Medium-gray, medium-bedded to laminated, fossiliferous, oolitic limestone containing edgewise conglomerate; to the west, Stonehenge is laterally equivalent to medium- to dark-gray, coarsely crystalline dolomite (Larke).
State Pennsylvania
Name Stonehenge/Larke Formation
Geologic age Ordovician
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone (Bed)medium-gray, medium-bedded to laminated, fossiliferous, oolitic limestone.
Minor
Sedimentary > Carbonate > Dolostone (Bed)Stonehenge is laterally equivalent to medium- to dark-gray, coarsely crystalline dolomite (Larke).
Incidental
Sedimentary > Clastic > Conglomerate (Bed)oolitic limestone containing edgewise conglomerate; to the west.
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 Centre - Clinton - Huntingdon