|Geologic age||Middle Devonian|
Sedimentary > Clastic > Mudstone > Shale
Sedimentary > Carbonate > Limestone
Sedimentary > Clastic > Mudstone > Shale > Black-shale
|Comments||part of Hamilton Group 200-500 ft. (60-150 m). Secondary unit descriptions from USGS Lexicon website (ref. NY046) and reference NY015: Skaneateles Shale of Hamilton Group extended from southwestern NY, western PA, and eastern OH into the subsurface of northern WV and far western MD (Garrett Co.). Unit consists mostly of dark- to medium-gray fossiliferous shale and mudrock. Contains a black shale facies that resembles the Marcellus Shale. Includes the Stafford Limestone Member at its base. The Stafford is thin but extensive and can be traced in the subsurface as far southwest as north-central WV and southeastern OH. The Skaneateles loses its identity to the west where the Hamilton is undivided. Grades into the Plum Brook Shale of northern OH or the lower part of the Olentangy Shale (deWitt and others, 1993). Stafford Limestone Member of Skaneateles Shale extended from southwestern NY into western PA and into the subsurface in eastern OH, northern WV, and far western MD (Garrett Co.). Marks the base of the Skaneateles and clearly separates it from the underlying Marcellus (de Witt and others, 1993).|
Fisher, D.W., Isachsen, Y.W., and Rickard, L.V., 1970, Geologic Map of New York State, consisting of 5 sheets: Niagara, Finger Lakes, Hudson-Mohawk, Adirondack, and Lower Hudson, New York State Museum and Science Service, Map and Chart Series No. 15, scale 1:250,000.
de Witt, Wallace, Jr., Roen, J.B. and Wallace, L.G., 1993, Stratigraphy of Devonian black shales and associated rocks in the Appalachian basin, IN Roen, J.B., and Kepferle, R.C., eds., Petroleum geology of the Devonian and Mississippian black shale of eastern North America: U.S. Geological Survey Bulletin, 1909-B, p. B1-B57.
USGS Geologic Names lexicon found at: http://ngmdb.usgs.gov/Geolex/
|Counties||Erie - Genesee - Livingston - Monroe - Ontario - Yates|