USGS Visual Identifier
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Geologic Unit: Yantic

Yantic Member of Tatnic Hill Formation (CT*,MA*)

Proterozoic, Late*
Ordovician, Middle*
Ordovician, Late(?)*
Geologic Province:
New England province*

Areal Extent:

Type Locality:
Type area: along boundary between Hampton and Danielson 7.5-min quadrangles, 0.25 to 0.5 mi east of Stetson Road, near village of Yantic, Norwich quadrangle, eastern CT (Dixon, 1964).

Unit Name History:
Named (Dixon, 1964).
Age modified; Isotopic dating (Zartman and others, 1965).
Age modified (Goldsmith, 1980).
Extended into MA (Goldsmith and others, 1982).
MA State Geol. Map usage (Zen and otehrs, 1983).
CT State Geol. Map usage (Rodgers, 1985).

Note: If you need more information, please contact Nancy Stamm (
Asterisks (*) indicate usage by the U.S. Geological Survey. Other usages by state geological surveys.

"No current usage" implies that a name has been abandoned or that it has fallen into disuse. Former usage and, if known, replacement name given in parentheses ().

Slashes (/) indicate unit name usage violates the 1983 North American Stratigraphic Code. This violation may be explained within brackets ([ ]).

U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
Database project personnel
Last modified: 15-Jan-2013