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Copake and Rochdale Formations

Copake and Rochdale Formations - Copake Formation-limestone, dolostone, siltstone; Rochdale Formation-limestone, dolostone; Halcyon Lake Dolostone-locally cherty.
State New York
Name Copake and Rochdale Formations
Geologic age Lower Ordovician
Comments part of Wappinger and Stockbridge Groups, Poughquag Quartzite, and Metamorphic Equivalents up to 4000 ft. (1200 m).
Primary rock type limestone
Secondary rock type dolostone (dolomite)
Other rock types siltstone; chert
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone
Minor
Sedimentary > Carbonate > Dolostone
Sedimentary > Clastic > SiltstoneCopake Formation
Incidental
Sedimentary > Chemical > ChertHalcyon Lake Dolostone-locally cherty.
Map references
NYS Museum, NYS Geological Survey, NYS Museum Technology Center, 1999, 1:250,000 Bedrock geology of NYS, data is distributed in ARC/INFOr EXPORT format (with ".e00" extension) in 5 seperate files based on printed map sheets, http://www.nysm.nysed.gov/gis.html.
Unit references
D. W. Fisher; Y. W. Isachsen, L. V. Rickard, 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 1:250000.