Usage:
Blackjack Formation of Hess Canyon Group (AZ)
[?] Blackjack Formation of Mazatzal Group (AZ)
Geologic age:
Mesoproterozoic
Type section, locality, area and/or origin of name:
Notable exposures in Blackjack Mountains and White Ledges, 20 mi north of Globe, AZ (Livingston, 1969).
AAPG geologic province:
Basin-and-Range 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 ([ ]).