- Usage in publication:
-
- Windy Gulch rhyolite breccia*
- Modifications:
-
- Named
- Dominant lithology:
-
- Rhyolite
- AAPG geologic province:
-
- San Juan Mountains province
Summary:
Windy Gulch rhyolite breccia of Piedra group of Potosi volcanic series. A rhyolite breccia, made up of light-colored rhyolite, in part an ordinary tuff, in part a normal flow rock, but chiefly a breccia, probably a flow breccia, in lower part of Piedra group of Potosi volcanic series. Underlies the tridymite latite of Piedra group in drainage basin of Windy Gulch, [Creede district, Mineral County, southwestern Colorado], and to west. Characterized by porous character and abundant fragments of pumice. Thickness 100 to 200+ feet. Age is Miocene.
Source: US geologic names lexicon (USGS Bull. 896, p. 2350).
- Usage in publication:
-
- Windy Gulch Member*
- Modifications:
-
- Revised
- AAPG geologic province:
-
- San Juan Mountains province
Summary:
Reduced in the San Juan Mountain province in stratigraphic rank as a formation (Emmons and Larsen, 1923) and assigned to the Bachelor Mountain Rhyolite as its upper member. Assigned a middle or late Tertiary age.
Source: GNU records (USGS DDS-6; Denver GNULEX).
- Usage in publication:
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- Windy Gulch Bed*
- Modifications:
-
- Revised
- Age modified
- AAPG geologic province:
-
- San Juan Mountains province
Summary:
Pg. A52-A53, A79. Windy Gulch Bed of Bachelor Mountain Member of Carpenter Ridge Tuff. Reduced in stratigraphic rank from Windy Gulch Member of Bachelor Mountain Tuff to Windy Gulch Bed, uppermost bed of Bachelor Mountain Member (revised) of Carpenter Ridge Tuff (revised). Overlies Campbell Mountain Bed (revised) of Bachelor Mountain Member. Is older than Mammoth Mountain Tuff (26.7 m.y.). Age changed from Oligocene --to-- late Oligocene.
Source: Publication.
- Usage in publication:
-
- Windy Gulch zone*
- Modifications:
-
- Revised
- AAPG geologic province:
-
- San Juan Mountains province
Summary:
Revised to informal status and is referred to as uppermost of three zones within Bachelor Mountain Member of Carpenter Ridge Tuff. Restudy of Creede area, Mineral Co, CO, San Juan Mountain province, has shown that within central part of Bachelor caldera in San Juan volcanic field, unit represents a zone of nonwelded tuff at top of upward sequence of progressively less welded zones within thick rhyolitic caldera fill. At margins of caldera welding zones, alternate and interfinger complexly. Unit previously thought to be a discrete eruptive deposit. Grades downward into Campbell Mountain zone (revised to informal status) of Bachelor Mountain; underlies Mammoth Mountain unit (revised to informal status) of Carpenter Ridge. Oligocene age (27.35 Ma).
Source: GNU records (USGS DDS-6; Denver GNULEX).
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 ([ ]).