Lithostratigraphy: Mammoth Cave Limestone Megagroup >>Salem Limestone >>Kidd Member
Chronostratigraphy: Paleozoic Erathem >>Mississippian Subsystem >>Valmeyeran Series
Allostratigraphy: Kaskaskia Sequence
Elwood Atherton, Charles Collinson, and Jerry A. Lineback
The Kidd Member of the Salem Limestone (Baxter, 1960a, p. 19-22; Lineback, 1972, p. 5), the basal member, is named for Kidd, Monroe County.
The type section of the Kidd Member is in the Mississippi River bluffs east of the village of Kidd, Monroe County (NE NE 1, 5S-10W).
Extent and Thickness
In the type section the Kidd consists of about 22 feet of chert-free, high-calcium biocalcarenite, largely made up of medium and coarse grains of fragmented fossils, mostly crinoid columnals and bryozoan detritus, in beds 2-3 feet thick.
As originally defined, it included the Harrodsburg Member of the Ullin Limestone, but it was restricted by Lineback to the biocalcarenite below the Fults Member and above the Ullin.
The foraminifers Endothyra sp., Tournayella sp., and Globoendothyra sp. are present. Globoendothyra baileyi is common and becomes more common in the upper half of the member.
BAXTER, J. W., 1960a, Salem Limestone in southwestern Illinois: Illinois State Geological Survey Circular 284, 32p.
LINEBACK, J. A., 1972, Lateral gradation of the Salem and St. Louis Limestones (Middle Mississippian) in Illinois: Illinois State Geological Survey Circular 474, 23 p.
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