Usage:
Orr Formation (UT*)
Subunits:
(alphabetical) --all in UT*: Big Horse Limestone Member, Candland Shale Member, Corset Spring Shale Member, Johns Wash Limestone Member, Sneakover Limestone Member, Steamboat Pass Shale Member.
Geologic age:
Late Cambrian*
Type section, locality, area and/or origin of name:
Type section (composite): two measured sections on northeast side of Orr Ridge, House Range, Millard Co., UT. Lower part on northeast face of hill 6593, in SE/4 sec. 28, T. 18 S., R. 13 W.; remainder in sec. 33, T. 18 S., R. 13 W., Notch Peak 15-min quadrangle (Hintze and Palmer, 1976).
Type locality: Orr Ridge, a spur extending east from main mass of Notch Peak, on south side of Weeks Canyon, House Range, [Millard Co.], western UT (Walcott, 1908).
AAPG geologic province:
Great Basin 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 ([ ]).