Usage:
Walcott Tuff (ID*)
Walcott Tuff of Heise Group (ID*-recognized locally in Heise volcanic field)
Geologic age:
late Tertiary (Miocene)*
Type section, locality, area and/or origin of name:
Named from Lake Walcott, where an excellent section is exposed in east bank [in vicinity of Massacre Rocks State Park], in SE/4 sec. 29, T. 8 S., R. 30 E., [Neeley 7.5-min quadrangle], Power Co., Snake River Plain, eastern ID (Stearns and Isotoff, 1956).
Reference section: measured at southern tip of Lemhi Range, on south-facing slope north of ID State Highway 33, in [SE/4 NW/4] sec. 35, T. 6 N., R. 30 E., Lat. 43 deg. 48 min. 19.1 sec. N., Long. 112 deg. 50 min. 52.3 sec. W., Big Lost River Sinks 7.5-min quadrangle, Butte Co., eastern Snake River Plain (northern margin), eastern ID (Morgan and McIntosh, 2005, Loc. 16).
AAPG geologic province:
Snake River basin*
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 ([ ]).