"Glenarm Wissahickon" formation (PAPZgw;0)

State	Pennsylvania
Name	"Glenarm Wissahickon" formation
Geologic age	Probably lower Paleozoic
Original map label	Xgw
Comments	Digital map differences from 1980 printed map: name and map symbol changed from (Wissahickon Formation - eastern part) (Xw).
Primary rock type	mica schist
Secondary rock type	mafic gneiss
Other rock types	amphibolite;
Lithologic constituents	Major Metamorphic > 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
Map references	Pennsylvania Bureau of Topographic and Geologic Survey, Department of Conservation and Natural Resources, 2001, Bedrock Geology of Pennsylvania, edition: 1.0, digital map. Retrieved from internet 9-30-2004; <http://www.dcnr.state.pa.us/topogeo/map1/bedmap.aspx> DL Data: pageoexp.zip [http://www.dcnr.state.pa.us/topogeo/map1/bedmap.aspx]
Unit 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, 2001, Bedrock Geology of Pennsylvania, edition: 1.0, digital map. Retrieved from internet 9-30-2004; <http://www.dcnr.state.pa.us/topogeo/map1/bedmap.aspx> DL Data: pageoexp.zip [http://www.dcnr.state.pa.us/topogeo/map1/bedmap.aspx]
Geographic coverage	Chester - Delaware - Montgomery