Allard Limestone Member
Lithostratigraphy: Pope Megagroup >>Menard Limestone >>Allard Limestone Member
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Chesterian Series >>Elviran Stage
Allostratigraphy: Kaskaskia Sequence
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.
Elwood Atherton, Charles Collinson, and Jerry A. Lineback
The Allard Limestone Member of the Menard Formation (Swann, 1963, p. 38-40).
Named for Allard College School, Johnson County.
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).
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.
The Allard Member is dominantly limestone.
Well log characteristics
Age and correlation
Environments of deposition
SWANN, D. H., 1963, Classification of Genevievian and Chesterian (Late Mississippian) rocks of Illinois: Illinois State Geological Survey Report of Investigations 216, 91 p.
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