Usage:
Chumstick Formation (WA*)
Subunits:
Nahahum Canyon Member (WA*).
Geologic age:
Tertiary
Eocene, middle*
Type section, locality, area and/or origin of name:
Type section: exposures along Eagle Creek beginning at its confluence with Chumstick Creek, in sec. 31, T. 25 N., R. 18 E., and extending northeast into sec. 20, T. 25 N., R. 19 E., north of Leavenworth, Chelan Co., WA (Gresens and others, 1981).
AAPG geologic province:
Northern Cascade Range-Okanagan province
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 ([ ]).