GEOLEX

Summary of Citation: Cap Mountain

Publication:
Paige, Sidney, 1911, Mineral resources of the Llano-Burnet
   region, Texas, with an account of the pre-Cambrian geology:
   U.S. Geological Survey Bulletin, 450, 103 p.

Usage in Publication:
Cap Mountain formation*

Modifications:	Geologic Province:	Dominant Lithology:
Named	Llano uplift	Limestone Sandstone

Summary:
Named for Cap Mountain, Llano quad, Llano Co, TX on Llano uplift. No type locality designated. Consists of, at base, a gradual transition from sandstone to limestone but predominantly limestone, capped by 15-75 ft of cross-bedded, glauconitic sandstone. Thickness is 90 ft. Underlies Wilberns formation; overlies Hickory sandstone. Correlates with Reagan sandstone in OK. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Ulrich, E.O., 1932, Preliminary description of the Honey Creek,
   Fort Sill, Royer, and Signal Mountain formations of Oklahoma:
   Geological Society of America Bulletin, v. 43, no. 3, p.
   742-747

Usage in Publication:
Cap Mountain formation

Modifications:	Geologic Province:	Dominant Lithology:
Areal limits	S. Oklahoma folded belt province	Dolomite

Summary:
One exposure of sandy dolomite--gray to greenish-pink, 126 ft thick, near east end of Arbuckle Mountains, OK, in South Oklahoma folded belt province--is identified as a local extension of Cap Mountain formation. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Decker, C.E., 1933, The Early Paleozoic stratigraphy of Arbuckle
   and Wichita Mountains [abs.]: Tulsa Geological Society Digest,
   p. 55-57

Usage in Publication:
Cap Mountain formation

Modifications:	Geologic Province:	Dominant Lithology:
Revised	S. Oklahoma folded belt province

Summary:
In the Arbuckle and Wichita Mountains, South Oklahoma folded belt province, the name Timbered Hills group is introduced to include (ascending): Reagan sandstone, Cap Mountain sandstone, and Honey Creek formation. (See Decker, 1939, for more complete description.) Cap Mountain is present in only one locality in OK. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Bridge, Josiah, 1937, The correlation of the upper Cambrian
   sections of Missouri and Texas with the sections in the upper
   Mississippi Valley [IN Shorter contributions to general
   geology]: U.S. Geological Survey Professional Paper, 186, p.
   233-237

Usage in Publication:
Cap Mountain formation*

Modifications:	Geologic Province:	Dominant Lithology:
Revised Areal limits Overview	Llano uplift

Summary:
In central TX, Llano uplift, the thick glauconitic sandstone at top of Cap Mountain formation is named Lion Mountain sandstone member. Named for Lion Mountain, Burnet quad, TX. Underlies Wilberns formation. In MO, the Bonneterre dolomite corresponds to uppermost Hickory sandstone and basal Cap Mountain formation. Correlation chart. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Lochman, Christina, 1938, Upper Cambrian faunas of the Cap
   Mountain formation of Texas: Journal of Paleontology, v. 12,
   no. 1, p. 72-85

Usage in Publication:
Cap Mountain formation

Modifications:	Geologic Province:	Dominant Lithology:
Biostratigraphic dating	Llano uplift

Summary:
In Burnett Co, TX on Llano uplift, consists of 220 ft of gray, crystalline limestone containing glauconite, overlain by a persistent 30-ft sandstone member, the Lion Mountain sandstone member. Basal beds are arenaceous and grade downward into Hickory sandstone. Cap Mountain characterized by having CEDARIA, CREPICEPHALUS, and APHELASPIS, and is equivalent to Eau Claire member of Dresbach formation of WI. Dresbach-Franconia break occurs in the barren, Lion Mountain sandstone member. Sandstone grades upward into limestones of Wilberns formation. Cross section. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Decker, C.E., 1939, Two Lower Paleozoic groups, Arbuckle and
   Wichita Mountains, Oklahoma: Geological Society of America
   Bulletin, v. 50, no. 8, p. 1311-1322

Usage in Publication:
Cap Mountain formation

Modifications:	Geologic Province:	Dominant Lithology:
Revised	S. Oklahoma folded belt province

Summary:
In Arbuckle and Wichita Mountains, OK, South Oklahoma folded belt province, the name Timbered Hills group is introduced with the Cap Mountain formation as the middle unit. Cap Mountain overlies Reagan sandstone and underlies Honey Creek formation, both of Timbered Hills group. Is present in only one locality in OK, a sandy, pinkish-green dolomite 125 ft thick. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Cloud, P.E., Jr., Barnes, V.E. and Bridge, Josiah, 1943,
   Stratigraphy of the Ellenburger group in central Texas; a
   progress report, IN Texas mineral resources: University of
   Texas-Austin, Bureau of Economic Geology Publication, no.
   4301, p. 133-161

Usage in Publication:
Cap Mountain limestone member*

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Llano uplift

Summary:
In central TX, Llano uplift, revised as Cap Mountain limestone member of Riley formation (new). Consists of 1) a lower portion of alternating dark-brown, impure limestone and calcareous sandstone, becoming more calcareous upward, and 2) an upper portion of brownish-gray, thick-bedded to massive limestone. Includes beds formerly included in underlying Hickory sandstone member of Riley. Is overlain by Lion Mountain sandstone member of Riley, which was formerly part of Cap Mountain formation. Thickness is 400 ft in Blanco Co, TX. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Bridge, Josiah, Barnes, V.E. and Cloud, P.E., Jr., 1947,
   Stratigraphy of the Upper Cambrian, Llano uplift, Texas:
   Geological Society of America Bulletin, v. 58, no. 1, p.
   109-123

Usage in Publication:
Cap Mountain limestone member*

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Llano uplift

Summary:
Riley formation in the study area (Llano uplift of central TX) ranges from about 600 to nearly 800 ft thick; it is thickest in southeast Llano Co. and thinnest in northwest corner of uplift; it overlies pre-Cambrian rocks; it underlies Wilberns formation; it is assigned a Late Cambrian age. Cross sections. Riley is divisible into the Hickory sandstone member, at base, Cap Mountain limestone member, in middle, and Lion Mountain sandstone member, at top. Upper boundary of Hickory modified; contact with overlying Cap Mountain placed at top of a noncalcareous sandstone beneath a zone of alternating impure dark brown limestone and calcareous sandstone; this contact is also a distinct topographic and vegetational break. The Hickory-Cap Mountain contact was previously placed at an indefinite point or thin the sequence. The upper contact of the Lion Mountain is revised in that Lion Mountain underlies the newly named Welge sandstone member of the Wilberns.

Summary of Citation: Cap Mountain

Publication:
Frederickson, E.A., 1948, Clarification of Upper Cambrian
   stratigraphy in Oklahoma: American Association of Petroleum
   Geologists Bulletin, v. 32, no. 7, p. 1349-1352

Usage in Publication:
Cap Mountain formation

Modifications:	Geologic Province:	Dominant Lithology:
Not used

Summary:
In Wichita and Arbuckle Mountains, OK, in South Oklahoma folded belt province, on basis of faunal evidence and stratigraphic position, Cap Mountain formation is included as part of Honey Creek formation. Cap Mountain not used. Age is Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Palmer, A.R., 1954, The faunas of the Riley formation in central
   Texas: Journal of Paleontology, v. 28, no. 6, p. 709-786

Usage in Publication:
Cap Mountain limestone member*

Modifications:	Geologic Province:	Dominant Lithology:
Biostratigraphic dating	Llano uplift

Summary:
In central TX, Llano uplift, faunal zones established do not correspond to lithic boundaries. Some fauna in basal portion may be late Middle Cambrian age. Age is Middle to Late Cambrian.

Summary of Citation: Cap Mountain

Publication:
Barnes, V.E. and Bell, W.C., 1977, The Moore Hollow Group of
   central Texas: University of Texas-Austin, Bureau of Economic
   Geology Report of Investigations, no. 88, 169 p.

Usage in Publication:
Cap Mountain Limestone Member

Modifications:	Geologic Province:	Dominant Lithology:
Revised Overview	Llano uplift Kerr basin Bend arch

Summary:
In central TX, Llano uplift, revised as middle member of Riley Formation of Moore Hollow Group (new). Moore Hollow Group includes Riley Formation below and Wilberns Formation above, and ranges in age from Middle Cambrian to Early Ordovician. Cap Mountain underlies Lion Mountain Sandstone Member with gradational boundary. To north in subsurface boundary placed where terrigenous material disappears and limestone dominant; to south boundary is at top of oolitic, massive, yellow-gray to light-olive-gray limestone. Thickness at surface 170-497 ft, thickening to southeast. In subsurface exceeds 500 ft to south in Kerr Co, south TX; to north it feathers out. To northwest across Llano uplift lower sandy unit of Cap Mountain replaced laterally by underlying Hickory sandstone. In subsurface all units grade laterally into Hickory Sandstone. Isopach map. Correlation chart. Geologic maps. Based on paleontology, age is Late Cambrian, Dresbachian.