- Usage in publication:
-
- Sams Spring Formation
- Modifications:
-
- First used
- Biostratigraphic dating
- Dominant lithology:
-
- Argillite
- Chert
- AAPG geologic province:
-
- Great Basin province
Summary:
[Name "Sams Spring" used in diagram by Kay (1960)]. Sams Spring Formation is 2nd from youngest formation (of 4) of Clipper Canyon Group. Contains several informal members of siliceous argillite, chert, and minor calcilutite. Thickness is about 500 ft. List of graptolites of Caradocian age indicates Ordovician age.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
- Usage in publication:
-
- Sams Spring Formation
- Modifications:
-
- Named
- Dominant lithology:
-
- Argillite
- Chert
- AAPG geologic province:
-
- Great Basin province
Summary:
Named for Sams Spring, a mi or so southeast of Petes Summit, Toquima Range, Lander Co, NV. Is second from youngest formation (of 4) in Clipper Canyon Group (new). Shown on map of Petes Summit Sheet, Nye and Lander Cos, NV. Is dark siliceous argillite in lower part, bedded dark chert in middle part, and siliceous argillite with interbeds of calcilutite succeeded by distinctive varicolored chert in upper part. Is about 500 ft thick. Overlies Petes Summit Formation; underlies Joes Canyon Formation (both new and of Clipper Canyon Group). Locally unconformably underlies Tertiary sedimentary and volcanic rocks. Graptolite fauna in lower part of unit are Caradocian. Age is given as Ordovician.
Source: GNU records (USGS DDS-6; Menlo 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 ([ ]).