- Usage in publication:
-
- West Fork series*
- Modifications:
-
- Named
- Dominant lithology:
-
- Quartzite
- Shale
- Limestone
- AAPG geologic province:
-
- Alaska East-Central region
Summary:
Crosses Chandalar River Valley in belt about 15 mi wide from below Granite Creek to above West Fork [of Chandalar River]. Probably has much wider distribution. Consists of fine-grained dark-gray quartzite, dark flint, calcareous black shale, and impure limestone. Seems to unconformably overlie basal granite on southeast and Lake quartzite-schist (new) on northwest. Intruded by dioritic and greenish diabasic dike. Age may be Paleozoic on basis of correlation with gravels below East Fork [of Chandalar River].
Source: GNU records (USGS DDS-6; Menlo GNULEX).
- Usage in publication:
-
- West Fork "series"*
- Modifications:
-
- Age modified
- Biostratigraphic dating
- AAPG geologic province:
-
- Alaska East-Central region
Summary:
West Fork "series" of Schrader (1900) is believed to be Late Devonian or Mississippian age based on fossils collected on Chandalar River and identified by G.H. Girty. One specimen of SPIRIFER DISJUNCTUS is definitely of Devonian age. Series is included in Upper Devonian or Mississippian rocks in map legend.
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 ([ ]).