| State | Pennsylvania |
|---|---|
| Name | Glenarm Wissahickon"" formation |
| Geologic age | Probably lower Paleozoic |
| Lithologic constituents |
Major
Metamorphic > Schist > Mica-schistlithologically similar to oligoclase-mica schist of the Wissahickon Formation (PZw)
Minor
Metamorphic > Gneisssome hornblende gneiss, augen gneiss (PZw)
Metamorphic > Amphibolitealso includes lenticular amphibolite bodies having ocean-floor basalt chemistry
|
| Comments | Digital map differences from 1980 printed map: name and map symbol changed from (Wissahickon Formation - eastern part) (Xw). |
| 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 | Chester - Delaware - Montgomery |