Elviran Stage
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)
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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).
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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
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