- Usage in publication:
-
- Clear Creek Canyon Formation
- Modifications:
-
- Named
- Dominant lithology:
-
- Gneiss
- Granite
- AAPG geologic province:
-
- Southern Rocky Mountain region
Summary:
Named for exposures at mouth of Clear Creek Canyon in SE1/4 sec 25 and north-central part sec 32, T3S, R70W, Golden quad, Jefferson Co, CO in Southern Rocky Mountain region. These exposures designated the type area. Called undivided interlayered gneisses in earlier reports. Consists of highly ptygmatically folded, migmatitic biotite gneisses and gneissic granite. Medium- to coarse-grained, concordant and discordant pegmatites intrude throughout; some range to as much as 25 ft thick. Estimated thickness of 5,000 ft. Lower contact is with Cedar Gulch Formation (new); upper contact is with Mount Vernon Canyon Formation (new). Cross section. Precambrian age.
Source: GNU records (USGS DDS-6; Denver GNULEX).
- Usage in publication:
-
- Clear Creek Canyon Formation
- Modifications:
-
- Overview
- AAPG geologic province:
-
- Southern Rocky Mountain region
Summary:
Is one of several units defined in a narrow belt along east-central Front Range, near Golden, Jefferson Co, CO in the Southern Rocky Mountain region. Of doubtful use elsewhere. Assumed direction of stratigraphic sequence is debatable. Belongs with pre-1,700 m.y. metamorphic complex, or of Precambrian X age.
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 ([ ]).