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Foreknobs Formation

Foreknobs Formation - Interbedded sandstone, siltstone, and shale; gray to olive gray, red near top; substantial brownish-gray sandstone; some marine fossils; a few conglomerate beds at base and top.
State Pennsylvania
Name Foreknobs Formation
Geologic age Devonian
Primary rock type sandstone
Secondary rock type siltstone
Other rock types shale; conglomerate
Lithologic constituents
Major
Sedimentary > Clastic > Sandstone (Bed)substantial brownish-gray sandstone
Minor
Sedimentary > Clastic > Siltstone (Bed)
Sedimentary > Clastic > Mudstone > Shale (Bed)
Incidental
Sedimentary > Clastic > Conglomerate (Bed)
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 Bedford - Blair - Fayette - Fulton - Huntingdon - Somerset