U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Riley

Usage:

Riley Formation of Moore Hollow Group (TX)
Riley Formation (TX*)


Subunits:

(alphabetical) --all in TX*: Cap Mountain Limestone Member, Hickory Sandstone Member, Lion Mountain Sandstone Member.


Geologic age:

Late Cambrian*


Type section, locality, area and/or origin of name:

Not designated; only complete section is Moore Hollow area, Riley Mountains, Llano Co., TX (Cloud and others, 1946).


AAPG geologic province:

Llano uplift*


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).