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Map showing publication footprint
  • Usage in publication:
    • Hennepin member
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Dolomite
  • AAPG geologic province:
    • Wisconsin arch
Publication:

Templeton, J.S., and Willman, H.B., 1952, Guidebook for the 16th annual field conference, central northern Illinois: Tri-State Annual Field Conference Guidebook, October 11-12, 1952, no. 16, 47 p., Also issued as Illinois State Geol. Survey Gdbk., 2nd ser., 1952. http://archive.org/details/guidebookforsixt02tris


Summary:

Figs. 3, 12. Hennepin member of Pecatonica formation. Dolomite, argillaceous, silty, thin-bedded. Shown on columnar section as underlying Chana member (new) and overlying Harmony Hill formation (new). Age is Middle Ordovician.
[Notable exposures in Dixon-Oregon area, northern IL.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 1733).


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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