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Map showing publication footprint
  • Usage in publication:
    • Necessity shale member
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Shale
  • AAPG geologic province:
    • Bend arch
Publication:

Sellards, E.H., 1933, The pre-Paleozoic and Paleozoic systems in Texas, Part 1, IN Sellards, E.H., Adkins, W.S., and Plummer, F.B, The geology of Texas; Volume 1, Stratigraphy: University of Texas Bulletin, no. 3232, p. 15-238., Published July, 1933


Summary:

Pg. 104, 113, 114. Necessity shale member of Graham formation. Replaces South Bend shale, which is preoccupied. Age is Pennsylvanian. [Origin of name not stated. Recognized in central northern Texas. On p. 113 he called it Necessity shale and sandstone.]

Source: US geologic names lexicon (USGS Bull. 896, p. 1471).


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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