- Usage in publication:
-
- Grossman Formation*
- Modifications:
-
- Named
- Dominant lithology:
-
- Conglomerate
- Siltstone
- Phyllite
- AAPG geologic province:
-
- Great Basin province
Summary:
Named for rocks in vicinity of Grossman Ranch in valley of Mill Creek about 1000 ft west of Owyhee-Mountain City 15' quad boundary. Type locality designated as hill, SE/4 sec.4 T45N R53E about 0.5 mi west of Grossman house, Grossman Ranch, Owyhee 15' quad, Elko Co, NV. Crops out in Mountain City and adjacent part of Owyhee 15' quads in 2 areas. Is dominantly clastic, ranging from coarse conglomerate to siltstone and phyllite. Thickness may be as much as 2000 ft. Unconformably overlies Valmy Formation. Unconformably underlies Banner Formation. Tentatively assigned to Devonian or Mississippian based on stratigraphic relations.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
- Usage in publication:
-
- Grossman Formation*
- Modifications:
-
- Age modified
- AAPG geologic province:
-
- Great Basin province
Summary:
Age revised from Devonian or Mississippian (Coats, 1969) to: Early Mississippian on basis of absence of post-Antler rocks of Devonian age in Carlin-Pinon Range area. Unit postdates beginning of Antler Orogeny (latest Devonian to Osagean). Shown on geologic map of Elko Co, NV.
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 ([ ]).