Nassau Formation

Shale, quartzite.
State New York
Name Nassau Formation
Geologic age Cambrian?
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > Quartzite
Sedimentary > Clastic > Mudstone > Shale
Comments part of Eugeosynclinal (Allochthonous) Sequence up to 4000 ft.? (1200 m). On printed map unit has a ? in front of Cn. Age changed to Late Proterozoic to Early 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

NGMDB product
Counties Dutchess