Acton Granite (MA*)
early or middle Paleozoic*
Named from town of Acton, Middlesex Co., eastern MA, where it is well exposed. Also exposed in Boxborough, Bolton, Harvard, Hudson, and Stow (Hansen, 1956).
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 ([ ]).