- Usage in publication:
-
- Alton coal group
- Modifications:
-
- Original reference
- Dominant lithology:
-
- Coal
- Shale
- Slate
- Clay
- AAPG geologic province:
-
- Appalachian basin
Summary:
Alton coal group in Pottsville formation. Chiefly shale, slate, and fire clay; usually contains 3 well-marked coal beds (Alton upper, Alton middle, and Alton lower). No limestone or calcareous beds. Thickness 20 to 35 feet. In Alton basin, in Lafayette Township, McKean County, central northern Pennsylvania, it is 30 to 35 feet thick. The lower coal is at base and its fire clay rests on Kinzua Creek [Connoquenessing] sandstone. Underlies Johnson Run [Homewood] sandstone. Is = Mercer coal group without question. Age is Pennsylvanian.
Source: US geologic names lexicon (USGS Bull. 896, p. 40-41).
- Usage in publication:
-
- Alton coal group
- Modifications:
-
- [Not used]
- AAPG geologic province:
-
- Appalachian basin
Summary:
Pg. 201. The Alton coal group of Ashburner in McKean County, central northern Pennsylvania, probably represents Mercer coals.
Source: US geologic names lexicon (USGS Bull. 896, p. 40-41).
- Usage in publication:
-
- Alto [Alton] coal group
- Modifications:
-
- Overview
- AAPG geologic province:
-
- Appalachian basin
Summary:
Alto [Alton] coal group in Pottsville formation. Same as Mercer shale member of Pottsville formation, the approved name. Recognized in McKean County, central northern Pennsylvania. Age is Pennsylvanian.
Source: US geologic names lexicon (USGS Bull. 896, p. 40-41).
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 ([ ]).