Tracy Creek Quartz Latite (CO*)
early Tertiary (Oligocene and Eocene?)*
Named from exposures along Tracy Creek [now Tracy Canyon]; Saguache and Del Norte quadrangles, [Saguache Co.], southwestern CO (Cross and Larsen, 1935).
San Luis basin*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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"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 ( ).
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