Elviran Stage

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Lithostratigraphy: Pope Megagroup
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

Elviran Stage (Swann, 1963, p. 23, 65), originally called the Elvira Group (J. M. Weller, 1939).

Derivation

Named for Elvira Township, Johnson County (12S-2E).

Other names

History/background

Type section

Type location

Type author(s)

Type status

Reference section

Reference location

Reference author(s)

Reference status

Stratigraphic relationships

The Elviran Stage is the youngest stage of the Chesterian Series. It includes the nine formations younger than the Glen Dean Limestone (fig. M-25).

Extent and thickness

Lithology

The limestones of the Elviran Stage are generally darker and finer grained and contain more silt and argillaceous material and less abundant fossils than the older Chesterian limestones.

Core(s)

Photograph(s)

Contacts

Well log characteristics

Fossils

Representative fossils include Pentremites fohsi, Pterotocrinus menardensis, Composita subquadrata, Eumetria costata, and Sulcatopinna missouriensis.

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.
WELLER, J. M., 1939, Mississippian System: Kansas Geological Society Guidebook, 13th Annual Field Conference, southwestern Illinois and southeastern Missouri, p. 131-137.

ISGS Codes

Stratigraphic Code Geo Unit Designation
4030
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