Usage:
Alder Group (AZ*)
Alder Formation (AZ*)
Subunits:
GROUP STATUS (alphabetical) --all in AZ: Board Cabin Formation, City Creek Formation, Flying W Formation, Houden Formation, McDowell Mountains Formation, Rackensack Canyon Formation, Reef Ridge Formation.
Geologic age:
Paleoproterozoic*
Type section, locality, area and/or origin of name:
Named from typical exposures in vicinity of Alder Creek, in central segment of Mazatzal Range, AZ. Crops out extensively in Mazatzal Mountains, eastern Tonto basin, Black Hills, and to small extent in Del Rio area (Wilson, 1937 [abs.], 1939).
AAPG geologic province:
Southwestern Basin-and-Range 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 ([ ]).