Beech Creek Limestone

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Lithostratigraphy: Pope Megagroup >>Okaw Group >>Golconda Group >>Beech Creek Limestone
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Chesterian Series >>Gasperian 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 Beech Creek Limestone (Malott, 1919, p. 11-15).

Derivation

Named for Beech Creek, Greene County, Indiana.

Other names

The Beech Creek is commonly called the "Barlow lime."

History/background

Type section

Type location

The type section of the Beech Creek Limestone is at the mouth of Ray's Cave, one fourth of a mile south of Beech Creek.

Type author(s)

Type status

Reference section

Reference location

Reference author(s)

Reference status

Stratigraphic relationships

Extent and thickness

The Beech Creek Limestone is a relatively thin limestone unit. It is very persistent and is widely used as a horizon for structure contour maps of the Illinois Basin (Bristol, 1968). The Beech Creek is unusual in that it thickens from south to north, counter to the trend of other Chesterian formations (fig. M-38). It is as much as 35-40 feet thick in the north but in areas in Hardin County it is thin, shaly, and difficult to identify. In some places the changes in thickness are abrupt and probably result from fusion of the formation with limestone beds that elsewhere are in the lower part of the Fraileys Shale.

Lithology

The lower part of the Beech Creek is argillaceous, dark brownish gray, dense to lithographic limestone, usually with scattered, black, rounded grains and a few fossils. The upper part is light brownish gray, fine to coarse grained, fossiliferous, and similar to much of the limestone higher in the Golconda Group. Some thin beds of oolitic limestone are present. The Beech Creek becomes somewhat sandy eastward, and in the vicnity of Saline and southern Hamilton Counties it seems to be represented locally by a bed of calcareous sandstone.

Core(s)

Photograph(s)

Contacts

Well log characteristics

Fossils

Euphemia randolphensis, a pelecypod, and Martinia contracta, a brachiopod, are characteristic of some beds in the Beech Creek.

Age and correlation

Environments of deposition

Economic importance

“Barlow” and “basal Golconda” are informal names applied to the Beech Creek Limestone.

Remarks

References

BRISTOL, H. M., 1968, Structure of the base of the Mississippian Beech Creek (Barlow) Limestone in Illinois: Illinois State Geological Survey Illinois Petroleum 88, 12 p.
MALOTT, C. A., 1919, "American Bottoms" region of eastern Greene County, Indiana-a type unit in southern Indiana physiography: Indiana University Studies, v. 6, 61 p.

ISGS Codes

Stratigraphic Code Geo Unit Designation
4350
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