Sonyea Group (NYDs;5)

State	New York
Name	Sonyea Group
Geologic age	Upper Devonian
Lithologic constituents	Major Sedimentary > Clastic > Mudstone > Shale Sedimentary > Clastic > Siltstone
Comments	200-1000 ft. (60-300 m). Secondary unit descriptions from USGS Lexicon website (ref. NY046) and reference NY015:In outcrop in western NY, the Sonyea consists of a basal black shale, the Middlesex Shale Member, and an upper gray shale with limestone nodules, the Cashaqua Shale Member. Members grade eastward into sequence of siltstone and silty shale, which is part of the general turbidite facies of the Catskill delta. The Middlesex is about 65 ft thick in the reference section 0.8 mi south of the village of Middlesex, Yates Co., NY. Thickens eastward to 75 ft at Chidsey Point Gully. Thins westward to 6 ft in Erie Co. Occurs in subsurface of PA, OH, WV, and MD, but is apparently is not present in VA. Makes up most of the Sonyea in the subsurface. The Cashaqua is thin, but recognizable from western NY, through PA and Garret Co., MD, to southwestern WV and has also been identified in southeastern OH. Age is Late Devonian (de Witt and others, 1993). Cashaqua Shale Member of Sonyea Formation extended from southwestern NY into western PA and into subsurface in eastern OH, WV, and westernmost MD (Garrett Co.) (de Witt and others, 1993).
References	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. https://pubs.er.usgs.gov/publication/b1909 USGS Geologic Names lexicon found at: http://ngmdb.usgs.gov/Geolex/ https://ngmdb.usgs.gov/Geolex/search
NGMDB product	NGMDB product page for 98670
Counties	Broome - Chemung - Chenango - Cortland - Livingston - Ontario - Schuyler - Seneca - Steuben - Tioga - Tompkins - Yates

State

New York

Name

Sonyea Group

Geologic age

Upper Devonian

Lithologic constituents

Major

Sedimentary > Clastic > Mudstone > Shale

Sedimentary > Clastic > Siltstone

Comments

200-1000 ft. (60-300 m). Secondary unit descriptions from USGS Lexicon website (ref. NY046) and reference NY015:In outcrop in western NY, the Sonyea consists of a basal black shale, the Middlesex Shale Member, and an upper gray shale with limestone nodules, the Cashaqua Shale Member. Members grade eastward into sequence of siltstone and silty shale, which is part of the general turbidite facies of the Catskill delta. The Middlesex is about 65 ft thick in the reference section 0.8 mi south of the village of Middlesex, Yates Co., NY. Thickens eastward to 75 ft at Chidsey Point Gully. Thins westward to 6 ft in Erie Co. Occurs in subsurface of PA, OH, WV, and MD, but is apparently is not present in VA. Makes up most of the Sonyea in the subsurface. The Cashaqua is thin, but recognizable from western NY, through PA and Garret Co., MD, to southwestern WV and has also been identified in southeastern OH. Age is Late Devonian (de Witt and others, 1993). Cashaqua Shale Member of Sonyea Formation extended from southwestern NY into western PA and into subsurface in eastern OH, WV, and westernmost MD (Garrett Co.) (de Witt and others, 1993).

References

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.

https://pubs.er.usgs.gov/publication/b1909

USGS Geologic Names lexicon found at: http://ngmdb.usgs.gov/Geolex/

https://ngmdb.usgs.gov/Geolex/search

NGMDB product

NGMDB product page for 98670

Counties

Broome - Chemung - Chenango - Cortland - Livingston - Ontario - Schuyler - Seneca - Steuben - Tioga - Tompkins - Yates