Usage:
Fraction Tuff (NV*)
Fraction Breccia (NV*)
Subunits:
(alphabetical) --all in NV: King Tonopah Member, Tonopah Summit Member.
Geologic age:
Tertiary*
Miocene*
Type section, locality, area and/or origin of name:
Not designated. Named from occurrences around Fraction No.1 and No. 2 mines, Tonopah mining district, Nye and Esmeralda Cos., NV (Spurr, 1905).
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 ([ ]).