U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Collinsville

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 usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).