Usage:
Lost Creek Tuff Member of Sepulcher Formation (MT*,WY*)
Lost Creek Tuff Member of Sepulcher Formation of Washburn Group of Absaroka Volcanic Supergroup (MT*,WY*)
Geologic age:
early Tertiary (Eocene)*
Type section, locality, area and/or origin of name:
Named from best and most accessible exposures in valley of Lost Creek, near Tower Falls Ranger Station, in Grand Canyon of the Yellowstone, northern part of Yellowstone National Park, [Tower Junction 7.5-min quadrangle, Park Co., northern WY] (Howard, 1937).
Type area: near Lost Creek, northwest of Tower Junction, [Tower Junction 7.5-min quadrangle, Park Co., northern WY] (Smedes and Prostka, 1972).
AAPG geologic province:
Montana folded belt*
Yellowstone 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 ([ ]).