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Coburn Formation through Nealmont Formation, undivided

Coburn Formation through Nealmont Formation, undivided - In descending order: Coburn Formation--medium-gray to very dark gray, very fossiliferous limestone and shaly limestone; Salona Formation--very dark gray to black, nonfossiliferous shaly limestone and calcareous shale containing metabentonite beds; Nealmont Formation--medium-gray fossiliferous limestone (calcarenite--Rodman Member) overlying thin-bedded shaly limestone (calcilutite--Center Hall Member).
State Pennsylvania
Name Coburn Formation through Nealmont Formation, undivided
Geologic age Ordovician
Primary rock type limestone
Secondary rock type shale
Other rock types metavolcanic rock; calcarenite
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone (Bed)Coburn Formation--medium-gray to very dark gray, very fossiliferous limestone and shaly limestone; Salona Formation--very dark gray to black, nonfossiliferous shaly limestone; Nealmont Formation--medium-gray fossiliferous limestone (calcarenite--Rodman Member) overlying thin-bedded shaly limestone (calcilutite--Center Hall Member).
Sedimentary > Clastic > Mudstone > ShaleCoburn Formation--medium-gray to very dark gray shaly limestone; Salona Formation--very dark gray to black, nonfossiliferous shaly limestone and calcareous shale containing metabentonite beds; Nealmont Formation--thin-bedded shaly limestone (calcilutite--Center Hall Member).
Minor
Metamorphic > Metaigneous > MetavolcanicSalona Formation--containing metabentonite beds
Sedimentary > Clastic > Sandstone > Arenite > Calcarenite (Bed)Nealmont Formation--medium-gray fossiliferous limestone (calcarenite--Rodman Member).
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
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
Counties Centre - Clinton - Huntingdon - Lycoming - Mifflin