Drury Shale Member (abandoned)

From ILSTRAT
Revision as of 16:31, 20 July 2020 by IlLex (talk | contribs) (Primary source)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Lithostratigraphy: McCormick Group >>Caseyville Formation >>Drury Shale Member
Chronostratigraphy: Paleozoic Erathem >>Pennsylvanian Subsystem >>Morrowan Series
Allostratigraphy: Absaroka Sequence

Primary source

Nelson, W.J., 2020, Pennsylvanian Subsystem in Illinois: Illinois State Geological Survey Bulletin (in press).
Edited and figures drafted by Jennifer M. Obrad.

Contributing author(s)

W.J. Nelson

Name

Original description

Lamar (1925, p. 91–95) divided the Pottsville Formation into four newly named members in the Carbondale, Illinois, 15-minute quadrangle. In ascending order, these were the Wayside sandstone and shale, the Lick Creek sandstone, the Drury sandstone and shale, and the Makanda sandstone. Among the four, only the name Wayside is still in use.

Derivation

The unit took its name from Drury Creek, a north-flowing tributary of the Big Muddy River in Union and Jackson Counties, southern Illinois.

Other names

None.

History/background

Figure 2-7. Chart showing the history of usage of the Drury Member. © University of Illinois Board of Trustees.

With the rise of cyclic classification, the Drury became a formation in the Caseyville Group (Wanless 1939). However, Weller (1940) and Wanless (1956) showed it as the Drury shale member of the Battery Rock formation. Kosanke et al. (1960) formalized the unit as the Drury Shale Member of the Caseyville Formation (Figure 2-7).

Remapping the southeastern part of the Carbondale 15-minute quadrangle, Nelson and Weibel (1996, p. 21) determined that the Drury Member, as mapped by Lamar (1925), “is largely in the lower part of the Tradewater Formation, although in some areas the Drury includes uppermost Caseyville strata.” Lamar’s original usage of Drury therefore conflicted with later usage, which placed the Drury entirely within the Caseyville. Rather than redefining the Drury, Nelson and Weibel opted to leave the interval unnamed. Additional factors favoring abandonment include extreme lithologic variability of the Drury and inability to demarcate the member in areas where either the Pounds or Battery Rock Sandstones cannot be identified.

Type section

None was designated or described.

References

  • Kosanke, R.M., J.A. Simon, H.R. Wanless, and H.B. Willman, 1960, Classification of the Pennsylvanian strata of Illinois: Illinois State Geological Survey, Report of Investigations 214, 84 p., 1 pl.
  • Lamar, J.E., 1925, Geology and mineral resources of the Carbondale Quadrangle: Illinois State Geological Survey, Bulletin 48, 173 p., 3 pls.
  • Nelson, W.J., and C.P. Weibel, 1996, Geology of the Lick Creek Quadrangle, Johnson, Union, and Williamson Counties, southern Illinois: Illinois State Geological Survey, Bulletin 103, 39 p., 1 pl.
  • Wanless, H.R., 1939, Pennsylvanian correlations in the Eastern Interior and Appalachian coal fields: Geological Society of America, Special Paper 17, 130 p., 9 pls.
  • Wanless, H.R., 1956, Classification of the Pennsylvanian rocks of Illinois as of 1956: Illinois State Geological Survey, Circular 217, 14 p.
  • Weller, J.M., 1940, Geology and oil possibilities of extreme southern Illinois: Illinois State Geological Survey, Report of Investigations 71, 71 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation
3890
--