Nassau Formation

South of 43 degrees; slate, shale, thin quartzite, includes Stuyvesant Conglomerate, Diamond Rock Quartzite, Curtis Mountain Quartzite, and Bomoseen Graywacke Members.
State New York
Name Nassau Formation
Geologic age Cambrian?
Lithologic constituents
Major
Sedimentary > Clastic > Mudstone > Shale
Minor
Metamorphic > Metasedimentary > Metaclastic > Slate
Metamorphic > Metasedimentary > Metaclastic > Quartziteincludes Diamond Rock Quartzite and Curtis Mountain Quartzite,
Sedimentary > Clastic > Conglomerateincludes Stuyvesant Conglomerate
Sedimentary > Clastic > Sandstone > GraywackeBomoseen Graywacke Member
Comments part of Eugeosynclinal (Allochthonous) Sequence up to 6000 ft.? (2000 m). Age changed to Late Proterozoic to Learly Cambrian as per USGS Lexicon website (ref. NY046) according to reference NY005.
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.

Ratcliffe, N.M., 1979, Field guide to the Chatham and Greylock slices of the Taconic allochthon in western Massachusetts and their relationship to the Hoosac-Rowe sequence, IN Friedman, G.M., ed., Joint annual meeting of New York State Geological Association, 51st annual meeting and New England intercollegiate geological conference, 71st annual meeting; Guidebook for field trips: New York State Geological Association Guidebook, no. 51, Joint annual meeting of New York State Geological Association, 51st, and New England Intercollegiate Geological Conference, 71st, Troy, NY, October 5-7, 1979, p.388-425.

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

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

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Counties Columbia - Greene - Rensselaer - Washington