- Usage in publication:
-
- Rockhill [Rock Hill] limestone
- Modifications:
-
- Original reference
- Dominant lithology:
-
- Limestone
- AAPG geologic province:
-
- Fort Worth syncline
Summary:
Pg. 14-16. Rockhill [Rock Hill] limestone. In Dry Creek is generally light-gray or dark-gray limestone in layers of moderate size. Very good horizon marker. In certain parts contains numerous crinoids and brachiopods. To southwest a mass of gray marls, 25 to 30 feet thick, is intercalated in lower part. Thickness of formation 30 to 150 or more feet; thickest to west. It forms high part of Rockhill Range [Bridgeport West 7.5-min quadrangle, Wise Co., central northern TX]. Rests on a series of gray marly shales with intercalated sandstones, and is separated from overlying Devils Den limestone by 305+/- feet of sandstones with intercalated shales. Lies 18-+/- feet above Bridgeport limestone. Appears to belong to Strawn formation. [Age is Pennsylvanian.]
Source: US geologic names lexicon (USGS Bull. 896, p. 428-429).
- Usage in publication:
-
- Rock Hill limestone member
- Modifications:
-
- Principal reference
- Dominant lithology:
-
- Limestone
- AAPG geologic province:
-
- Fort Worth syncline
Summary:
Pg. 30. Rock Hill limestone member of Graford formation. Overlies Lake Bridgeport shales and underlies Jasper Creek shales. It forms the flat top of the long, narrow ridge (Rock Hill) that extends southwest from south end of Lake Bridgeport dam, [Wise County, central northern Texas]. It is a tongue of Chico Ridge limestone. [Age is Pennsylvanian.]
Source: US geologic names lexicon (USGS Bull. 896, p. 1829).
- Usage in publication:
-
- Rock Hill Limestone Member
- Modifications:
-
- Mapped 1:250k
- Dominant lithology:
-
- Limestone
- AAPG geologic province:
-
- Fort Worth syncline
Summary:
Pamphlet [p. 14-15]. Rock Hill Limestone Member of Chico Ridge Limestone of Canyon Group. Mottled pale-yellowish-brown, well-indurated, characteristically brecciated with angular intraclasts up to 2 inches long, thick-bedded, massive, clasts and fossils weather in relief. Thickness 2 feet, thickens northward. [Intertongues with Jasper Creek Formation of Canyon Group; separates the Jasper Creek into upper (Jasper Creek beds) and basal (Lake Bridgeport shales) parts]; interval between Rock Hill and base of Jasper Creek Formation increases noticeably to the north. = and merges with lower part of thick Chico Ridge Limestone.
[Mapped in Lake Bridgeport area, Jack and Wise Cos., central northern TX; western edge of map sheet. Rocks previously (1967 ed. of map) mapped as Rock Hill Limestone Member of Graford Formation. See also adjacent Wichita Falls-Lawton sheet, Texas Geol. Atlas, 1987.]
Source: Publication.
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 ([ ]).