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Map showing publication footprint
  • Usage in publication:
    • Shadrick Mill sandstone
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Sandstone
    • Conglomerate
  • AAPG geologic province:
    • Bend arch
Publication:

Drake, N.F., 1893, Report on the Colorado coal field of Texas, IN Fourth annual report of the Geological Survey of Texas, 1892: Geological Survey of Texas Annual Report, v. 4, p. 357-444. [Available online from the University of Texas-Austin library: http://www.lib.utexas.edu/books/dumble/]


Summary:

Pg. 374, 376. Shadrick Mill sandstone in Strawn division. Sandstone, usually massive but with some flaggy beds and a thin conglomerate. Thickness 150 feet. Member of Strawn division [Strawn is 2nd from base of 5 Carboniferous divisions of Cummins, 1891]. Overlies Elliott Creek bed and underlies Bed No. 8 (250 to 300 feet of clay interstratified with sandstone at base). Age is Pennsylvanian.
[Named from Shadrick Mill, Lampasas Co., Colorado River region, central TX.]

Source: US geologic names lexicon (USGS Bull. 896, p. 1963).


Map showing publication footprint
  • Usage in publication:
    • Shadrick Mill sandstone
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Fort Worth syncline
Publication:

Zimmerman, D.A., and Glover, G.D., 1956, Summary of geological nomenclature, Morrow, Bend, and Strawn series, Fort Worth basin area [Texas]: Society of Economic Paleontologists and Mineralogists, Permian Basin Section, Field Trip Guidebook, Spring meeting and field symposium, May 11-12, 1956, p. 70-78.


Summary:

Pg. 76. Shadrick Mill sandstone in Strawn series. Sandstone, commonly massive but with some flaggy beds and thin conglomerate. Thickness 150 feet. Overlies Elliott Creek bed; underlies bed No. 8. [Age is Pennsylvanian; age of Strawn not discussed.]
[Report area in Parker County, central Texas.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 3542); supplemental information from 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 ([ ]).

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