- Usage in publication:
-
- Oak Point Granite
- Modifications:
-
- Named
- Geochronologic dating
- Dominant lithology:
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- Granite
- AAPG geologic province:
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- New England province
Summary:
Named the Oak Point Granite in Penobscot Bay, coastal south-central ME. Unit was dated by Rb-Sr (whole rock) as 357+\-1 Ma and therefore Mississippian (or latest Devonian). The Oak Point is older than the Stonington Granite.
Source: GNU records (USGS DDS-6; Reston GNULEX).
- Usage in publication:
-
- Oak Point Granite*
- Modifications:
-
- Overview
- Age modified
- Geochronologic dating
Summary:
Oak Point Granite in northern Penobscot Bay consists of light-reddish-gray to brick-red, medium-grained, coarsely porphyritic hornblende-biotite granite with subhedral phenocrysts of flesh-colored microcline and cream-colored oligoclase. Angular inclusions of country rock are numerous. Mississippian age is based on Rb-Sr whole-rock age of 349+/-1 Ma, recalculated from Brookins and Spooner (1970).
Source: GNU records (USGS DDS-6; Reston GNULEX).
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 ([ ]).