- Usage in publication:
-
- Trimmers Rock sandstone
- Modifications:
-
- Named
- Dominant lithology:
-
- Sandstone
- AAPG geologic province:
-
- Appalachian basin
Summary:
Named Trimmers Rock sandstone for hill east of Newport, Perry Co., PA. The name supplants Ithaca because of the more inclusive nature of beds in Pennsylvania than the typical Ithaca. Unit is equivalent to the Brallier shale in part and is considered of Late Devonian age.
Source: GNU records (USGS DDS-6; Reston GNULEX).
- Usage in publication:
-
- Trimmers Rock Formation*
- Modifications:
-
- Revised
- AAPG geologic province:
-
- Appalachian basin
Summary:
Upper Devonian Trimmers Rock Formation divided into descending: Millrift Member and Sloat Brook Member. Trimmers Rock Formation in Pike County is 1,825 ft thick. Consists of light to dark gray siltstone, shale, and fine-grained sandstone. Has massive bedding and well-developed joint system. Sandstone and siltstone resistant to weathering and form ledges.
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 ([ ]).