Gravina Island Formation (AK*)
Late Jurassic and Early Cretaceous*
Type area: Blank Inlet area along southeastern shore of Gravina Island, in parts of Ketchikan A-6, B-5, and B-6 quadrangles (scale 1:63,360), AK (Berg, 1973).
Alaska Southeastern region*
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 ([ ]).