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Middlebury and Chazy Limestone, Undifferentiated Youngman and Carman Formations, Crown Point Member

Middlebury and Chazy Limestone, Undifferentiated Youngman and Carman Formations, Crown Point Member - Massive, characterized by abundant Maclurites magnus.
State Vermont
Name Middlebury and Chazy Limestone, Undifferentiated Youngman and Carman Formations, Crown Point Member
Geologic age Ordovician
Comments Part of Champlain and Vermont Valleys, Chazy Group Secondary unit description from USGS Geologic Names lexicon (ref. VT030): Revised the Crown Point to the Crown Point member of the Chazy limestone in VT. Consists of massive limestone with characteristic MACLURITES MAGNUS fossils. Overlies the Day Point member and underlies the Valcour member, both of the Chazy limestone. The Crown Point is of Middle Ordovician age.
Primary rock type limestone
Secondary rock type
Other rock types
Lithologic constituents
Major
Sedimentary > Carbonate > LimestoneMassive, characterized by abundant Maclurites magnus.
Map references
Nicholson, S.W., Dicken, C.L., Horton, J.D., Foose, M.P., Mueller, J.A.L., and Hon, Rudi, 2006, Preliminary integrated geologic map databases for the United States: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, Rhode Island, and Vermont: U.S. Geological Survey Open-File Report 2006-1272.
Unit references
Doll, C.G., Cady, W.M., Thompson, J.B., Jr., and Billings, M.P., 1961, Centennial Geologic Map of Vermont: Vermont Geological Survey, Miscellaneous Map MISCMAP-01, scale 1:250,000.
USGS Geologic Names Lexicon (GEOLEX)
Counties Addison - Chittenden - Grand Isle