Historical:Negli Creek Limestone Member
Lithostratigraphy: Pope Megagroup >>Kinkaid Limestone >>Negli Creek Limestone Member
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Chesterian Series >>Elviran Stage
Allostratigraphy: Kaskaskia Sequence
Authors
Elwood Atherton, Charles Collinson, and Jerry A. Lineback
Name Origin
The Negli Creek Limestone Member of the Kinkaid Formation (Logan, 1924, p. 11, 125; Malott, 1925, p. 112-114; Swann, 1963, p. 75), the lowermost member, is named for Negli Creek, Perry County, Indiana.
Type Section
The type section of the Negli Creek Limestone Member is located along Negli Creek, Perry County, Indiana, in an exposure of 12 feet of limestone (NW 36, 6S-3W).
Extent and Thickness
The Negli Creek Limestone thickens southward from 16 feet in Effingham County to 37 feet in Franklin County.
Description
In Illinois the Negli Creek Limestone Member is a massive limestone very similar in thickness and lithology to the Goreville Limestone Member but more extensive. Most of the limestone is brownish gray, but it has some light gray and brown beds. It is very fine grained but includes coarse grains of fossils. In places the lower part is lithographic. It is cherty, particularly in the upper part, but generally less cherty than the Goreville Member.
Fossils
Algal growths (Girvanella) are common in the lower part of the Negli Creek, and large gastropods and small biserial Foraminifera occur near the middle.
References
LOGAN, W. N., 1924, Geological conditions in the oil field of southwestern Indiana: Indiana Department of Conservation Publication 42, 125 p.
MALOTT, C. A., 1925, Upper Chester of Indiana: Indiana Academy of Science Proceedings (1924), v. 34, p. 103-132.
SWANN, D. H., 1963, Classification of Genevievian and Chesterian (Late Mississippian) rocks of Illinois: Illinois State Geological Survey Report of Investigations 216, 91 p.
ISGS Codes
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