Usage:
Adel Mountain Volcanics (MT*)
Geologic age:
Late Cretaceous to Paleocene*
Type section, locality, area and/or origin of name:
[Type locality not designated. Adel Mountain volcanics occupy approx. 330 sq mi of northern Big Belts, northwestern MT. Adel Mountain (now Sieben), Lat. 47 deg. 04 min. 34 sec. N., Long. 111 deg. 42 min. 24 sec. W, Hound Creek Reservoir 7.5-min quadrangle, Cascade Co., northwestern MT.]
AAPG geologic province:
Sweetgrass arch*
Montana folded belt*
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 ([ ]).