Usage:
Collinsville Formation (CT*,MA*)
Subunits:
Bristol (CT*,MA*) and Sweetheart Mountain (CT*,MA*). Members; unnamed hornblende gneiss member (CT), unnamed metaquartzite member (CT)
Geologic age:
Middle Ordovician*
Type section, locality, area and/or origin of name:
Between highest and lowest water level of Nepaug Reservoir, on southern face of Sweetheart Mountain, near village of Collinsville, Canton Twp., Hartford Co., northern central CT (Gregory, 1906).
AAPG geologic province:
New England province*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).