- Usage in publication:
-
- Ninuluk formation*
- Modifications:
-
- Named
- Biostratigraphic dating
- Dominant lithology:
-
- Siltstone
- Shale
- AAPG geologic province:
-
- Alaska Northern region
Summary:
Named as formation (of 4) of Nanushuk Group. Type locality designated on right bank of Colville River at Ninuluk Bluffs 20 mi downstream from junction of Killik and Colville Rivers at 69 deg 08'N, 153 deg 18'W, which is location of measured type section. Consists of greenish gray siltstone, silt shale, and dark blue-gray shale (about 60 %) and coarse clastics [about 40%]. Thickness at type is 657 ft and in addition 261 ft of interfingering Niakogen tongue of Chandler formation (Nanushuk Group) are exposed in about middle of marine Ninuluk formation. Conformably overlies Grandstand formation (new) of Nanushuk Group and Killik tongue (new) of Chandler formation. Unconformably underlies Seabee formation of Colville Group. Age is Late Cretaceous based on late Cenomanian fossils (listed in type section).
Source: GNU records (USGS DDS-6; Menlo GNULEX).
- Usage in publication:
-
- Ninuluk Formation†
- Modifications:
-
- Abandoned
- AAPG geologic province:
-
- Alaska Northern region
Summary:
Pg. 5 (fig. 4), 6-8 (table 1), 12. †Ninuluk Formation of †Colville Group. Abandoned. (†Colville also abandoned.) Rocks reassigned to unnamed upper part (nonmarine) of Nanushuk Formation (revised). [See Nanushuk.]
Source: Publication.
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 ([ ]).