- Usage in publication:
-
- Carys Mill Formation*
- Modifications:
-
- Named
- Biostratigraphic dating
- Dominant lithology:
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- Limestone
- Siltstone
- Slate
- AAPG geologic province:
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- New England province
Summary:
Named as a formation in Meduxneag Group (rank raised). Named for community of Carys Mills, Aroostook Co., northeast ME. Formerly called ribbon rock member of Meduxnekeag Formation. Consists of gray-blue limestone and calcareous siltstone interbedded with buff-weathered ankeritic limestone and with gray and green slate. Slate and slate with graywacke lenses present at different stratigraphic levels in Bridgewater quad. Thickness about 12,000 ft in Bridgewater quad. Conformably underlies and grades into Smyrna Mills Formation. Age is Middle Ordovician through Early Silurian (Caradoc through Llandovery age). Age of upper part of formation based on middle Llandovery graptolite MONOGRAPTUS cf. M. CYPHUS reported from these rocks by Pavlides and Berry (1965).
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 ([ ]).