Hombergian Stage

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Lithostratigraphy: Pope Megagroup
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Chesterian Series >>Hombergian 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

Hombergian Stage (Swann, 1963, p. 22, 70), derived from the Homberg Group (J. M. Weller, 1939).

Derivation

Named for Homberg, Pope County.

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 Hombergian Stage is the middle stage of the Chesterian Series.

Extent and thickness

Lithology

The Hombergian Stage includes strata from the top of the Beech Creek up to the top of the Glen Dean (fig. M-25). The limestones in this stage are typically light brownish gray, light gray, or buff to gray and many of them and their associated shales are abundantly fossiliferous. Red shales in the upper part of the Fraileys and the lower part of the Hardinsburg are extensive marker beds.

Core(s)

Photograph(s)

Contacts

Well log characteristics

Fossils

The bryozoan Prismopora serrulata and the crinoid Pterotocrinus (fig. M-4) are typical Hombergian 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.
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
4250
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