Allard Limestone Member

From ILSTRAT
Jump to navigation Jump to search

Lithostratigraphy: Pope Megagroup >>Menard Limestone >>Allard Limestone Member
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Chesterian Series >>Elviran Stage
Allostratigraphy: Kaskaskia Sequence

Primary source

Willman, H. B., Elwood Atherton, T. C. Buschbach, Charles Collinson, John C. Frye, M. E. Hopkins, Jerry A. Lineback, and Jack A. Simon, 1975, Handbook of Illinois Stratigraphy: Illinois State Geological Survey Bulletin 95, 261 p.

Contributing author(s)

Elwood Atherton, Charles Collinson, and Jerry A. Lineback

Name

Original description

The Allard Limestone Member of the Menard Formation (Swann, 1963, p. 38-40).

Derivation

Named for Allard College School, Johnson County.

Other names

History/background

Type section

Type location

The Allard Limestone Member is located 2.2 miles southwest of Allard College School, Johnson County, in a cut at the south end of the Illinois Central Railroad tunnel (SW NW NE 1, 13S-4E).

Type author(s)

Type status

Reference section

Reference location

Reference author(s)

Reference status

Stratigraphic relationships

Extent and thickness

The Allard ranges from a little more than 30 feet in the far south to 10-12 feet in much of the northern area of the Menard.

Lithology

The Allard Member is dominantly limestone.

Core(s)

Photograph(s)

Contacts

Well log characteristics

Fossils

Age and correlation

Environments of deposition

Economic importance

Remarks

References

SWANN, D. H., 1963, Classification of Genevievian and Chesterian (Late Mississippian) rocks of Illinois: Illinois State Geological Survey Report of Investigations 216, 91 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation
4180
--