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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Richardson subgroup [informal]
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Shale
    • Limestone
  • AAPG geologic province:
    • Forest City basin
    • Nemaha anticline
Publication:

Condra, G.E., 1935, Geologic cross-section, Forest City, Missouri to south of Du Bois, Nebraska: Nebraska Geological Survey Paper, no. 8, 23 p., Issued late in 1935. See also USGS unpub. corr. charts of Pennsylvanian and Permian rocks of KS and NE, compiled by M.G. Wilmarth, Secretary of Committee on Geologic Names, Oct. 1936


Summary:

Pg. 4, 5, 9. Richardson subgroup [informal] of Wabaunsee group. Top subgroup of Wabaunsee group. Thickness 80+ feet. Includes Brownville limestone at top and extends down to top of Tarkio limestone (Brownville limestone, 2 to 4 feet; Pony Creek shale, 57 feet; Dover limestone, 1.5 to 4 feet; McKissick [Grove] shale, 10 to 19 feet).
Type locality: the Big Nemaha Valley of southern Richardson Co., southeastern NE, between points south of Humboldt and southwest of Falls City. Named from Richardson Co.
See also "Modern classifications of the Pennsylvanian rocks of eastern Kansas and southeastern Nebraska," compiled by M.G. Wilmarth, Secretary of Committee on Geologic Names, USGS unpub. corr. chart, Oct. 1936, sheet 2.
["Subgroup" not recognized as a formal stratigraphic rank term (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). Considered informal and should not be capitalized.]

Source: US geologic names lexicon (USGS Bull. 896, p. 1808); GNC KS-NE Pennsylvanian Corr. Chart, sheet 2, Oct. 1936.


Map showing publication footprint
  • Usage in publication:
    • Richardson subgroup [informal]
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Nemaha anticline
    • Forest City basin
    • Cherokee basin
Publication:

Moore, R.C., and Mudge, M.R., 1956, Reclassification of some Lower Permian and Upper Pennsylvanian strata in northern Midcontinent, IN Geological notes: American Association of Petroleum Geologists Bulletin, v. 40, no. 9, p. 2271-2278. [Available online, with subscription, from AAPG archives: http://www.aapg.org/datasystems or http://search.datapages.com]


Summary:

Pg. 2274 (fig. 1), 2277. Richardson subgroup [informal]. Nemaha-Richardson boundary lowered to base of Tarkio limestone herein reduced to member status in newly proposed Zeandale formation. This change has been agreed to by the Nebraska and Kansas Geological Surveys which are chiefly concerned. As herein redefined, the Richardson subgroup comprises five formations (ascending): Zeandale limestone, Pillsbury shale, Stotler limestone, Root shale, and Wood Siding formation (with Brownville limestone member at top). Age is Late Pennsylvanian (Virgilian).
["Subgroup" not recognized as a formal stratigraphic rank term (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). Considered informal and should not be capitalized.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 3260).


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