MAP 7 COMMONWEALTH OF PENNSYLVANIA GEOLOGIC MAP OF PENNSYLVANIA DEPARTMENT OF CONSERVATION AND NATURAL RESOURCES SCALE 1:2,000,000 BUREAU OF TOPOGRAPHIC AND GEOLOGIC SURVEY www.dcnr.state.pa.us/topogeo 80° 0 10 20 30 40 50 MI

ERIE 0 20 40 60 80 KM LAKE 79° 77° 76° 78° N. Y. 42° N. Y. 42° ERIE WARREN McKEAN POTTER TIOGA BRADFORD SUSQUEHANNA

DELAWARE

WAYNE CRAWFORD

WYOMING 75° ELK SULLIVAN FOREST CAMERON N. Y.

LACKAWANNA PIKE VENANGO LUZERNE

LYCOMING N. J. MERCER MONROE

BUTLER COLUMBIA MONTOUR CLARION CLINTON 41° 41° JEFFERSON UNION 75° LAWRENCE INDIANA CARBON BEAVER CLEARFIELD SNYDER CENTRE ARMSTRONG NORTHAMPTON SCHUYLKILL LEHIGH OHIO CAMBRIA MIFFLIN NORTHUMBERLAND ALLEGHENY JUNIATA BERKS BLAIR 75°

W. VA. PERRY BUCKS RIVER LEBANON HUNTINGDON DAUPHIN

MONTGOMERY WESTMORELAND CUMBERLAND WASHINGTON

40° 40° FULTON 75° SOMERSET PHILADELPHIA ADAMS FRANKLIN DELAWARE LANCASTER GREENE BEDFORD CHESTER DEL. N. J. FAYETTE YORK W. VA. MD. MD. 80° 79° 78° 77° 76° EXPLANATION * QUATERNARY TERTIARYJURASSIC AND PERMIAN PENNSYLVANIAN MISSISSIPPIAN DEVONIAN SILURIAN ORDOVICIAN CAMBRIAN LOWER PRECAMBRIAN (0–1.8 mil. yrs.) (1.8–65 mil. yrs.) TRIASSIC (248–290 mil. yrs.) (290–323 mil. yrs.) (323–354 mil. yrs.) (354–417 mil. yrs.) (417–443 mil. yrs.) (443–490 mil. yrs.) (490–570 mil. yrs.) PALEOZOIC (older than 570 Sand, gravel, and Sand, gravel, silt, (144–248 mil. yrs.) Cyclic sequences of Cyclic sequences of Red and gray sand- Red sandstone, Red and gray sand- Shale, limestone, Limestone, dolo- (443–570 mil. yrs.) mil. yrs.) silt. and clay. Red sandstone, shale, sandstone, sandstone, red and stone, shale, and gray shale, black stone, conglomer- dolomite, and sand- mite, sandstone, Metamorphic rocks Gneiss, granite, Sand and gravel. Sand and gravel. shale, and conglom- limestone, and coal. gray shale, con- limestone. shale, limestone, ate, shale, and lime- stone. shale, quartzite, and (metasedimentary anorthosite, meta- erate (green), in- Lime, clay. glomerate, clay, Flagstone, lime- and chert. stone. Slate, limestone, phyllite. and meta-igneous); diabase, metaba- truded by diabase coal, and limestone. stone, clay. Flagstone, silica Lime, building stone. zinc, clay. Lime, building stone. schist, gneiss, quartz- salt, metarhyolite, (red). Coal, clay, lime, sand, clay, lime. ite, serpentine, slate, and marble. Building stone, iron. building stone. and marble. Building stone, Building stone, talc. graphite, sericite.

*Cretaceous rocks, which are present in small areas of southern Montgomery County, cannot be shown at the scale of this map. 2200–MP–DCNR0498 Prepared by Bureau of Topographic and Geologic Survey. Third Edition, 1990; Fourth Printing, Slightly Revised, 2007. Printed on Recycled Paper