Historical:Drury Shale Member

From ILSTRAT
Revision as of 11:21, 25 July 2018 by ILSTRAT (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search
Handbook of Illinois Stratigraphy
Series Bulletin 95
Author H. B. Willman, Elwood Atherton, T. C. Buschbach, Charles Collinson, John C. Frye, M. E. Hopkins, Jerry A. Lineback, Jack A. Simon
Date 1975
Link Web page
PDF PDF file
Store ISGS Store

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

Authors

M. E. Hopkins and J. A. Simon

Name Origin

The Drury Shale Member of the Caseyville Formation (Lamar, 1925, p. 91-95) is named for Drury Creek in Jackson County.

Type Section

The type section consists of exposures along Drury Creek south of Makanda (33, 34, 10S-1W).

Correlation

The Drury is equivalent to part of the Mansfield Sandstone of Indiana.

Extent and Thickness

The Drury is as much as 100-150 feet thick in places near the type area, but the thickness varies somewhat, partly because of differential erosion prior to deposition of the overlying Pounds Sandstone.

Stratigraphic Position

All strata lying between the Battery Rock and Pounds Sandstones are considered equivalent to the Drury, but, for the sake of clarity in classification, the name "Drury" is not used in parts of southeastern Illinois where two other members of the Caseyville Formation - the Sellers Limestone and the Gentry Coal - occur within the Drury interval.

Description

The Drury is a complex unit of sandy or silty shale, siltstone, and lenticular massive sandstone units, and is much like the Lusk Shale. It contains at least two thin, nonpersistent coals. Although rocks of Drury age are present in the subsurface of the southern part of the Illinois Basin, the Battery Rock and Pounds Sandstones cannot generally be differentiated in well logs, which makes it impractical to differentiate the Drury.

References

LAMAR, J. E., 1925, Geology and mineral resources of the Carbondale Quadrangle: Illinois State Geological Survey Bulletin 48, 172 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation
3890
--