Emporia Formation
Appearance
Emporia Formation Emporia Limestone | |
---|---|
Stratigraphic range: [1] (Virgilian stage)[2] | |
Type | Formation |
Unit of | Wabaunsee Group Oklahoma: Vamoosa Group |
Sub-units |
|
Underlies | Willard Shale |
Overlies | Auburn Shale |
Lithology | |
Primary | Limestone, shale |
Other | Sandstone |
Location | |
Region | Kansas |
Country | United States |
Type section | |
Named for | Emporia, Kansas |
Named by | R.C. Moore and M.R. Mudge[2] |
Year defined | 1956 |
The Emporia Formation, also referred to as Emporia Limestone, is a Late-Carboniferous geologic formation in Kansas, extending into Nebraska, Iowa, Missouri, and Oklahoma.[2][1]
This formation's members are, top to bottom,
- Elmont Limestone, named for Elmont, Kansas (Beede, 1898)[3]
- Harveyville Shale, named for Harveyville, Kansas (Moore, 1936)[4]
- Reading Limestone, named for Reading, Kansas (Moore, 1936)[5]
While the Elmont Limestone member is generally less than 3 feet thick (1 meter), it can be as thick as 15 feet (5 meters)[3] and as thin as 12 inches. As thin as that, it is particularly resistant and forms multiple waterfalls in southern Riley County, including Pillsbury Crossing.[6][7]
See also
[edit]References
[edit]- ^ a b P. H. Heckel (2013). "Pennsylvanian stratigraphy of Northern Midcontinent Shelf and biostratigraphic correlation of cyclothems". Stratigraphy. 10 (1–2): 7, TEXT-FIGURE 4. Retrieved 2024-06-02.
- ^ a b c "Geologic Unit: Emporia". National Geologic Database. Geolex — Significant Publications. United States Geological Survey. Retrieved 2024-06-02.
- ^ a b "Geologic Unit: Elmont". National Geologic Database. Geolex — Significant Publications. United States Geological Survey. Retrieved 2024-06-02.
- ^ "Geologic Unit: Harveyville". National Geologic Database. Geolex — Significant Publications. United States Geological Survey. Retrieved 2024-06-02.
- ^ "Geologic Unit: Reading". National Geologic Database. Geolex — Significant Publications. United States Geological Survey. Retrieved 2024-06-02.
- ^ Jewett, John M. (1941). The Geology of Riley and Geary Counties, Kansas, Kansas Geological Survey Bulletin 39. University of Kansas Publications, State Geological Survey of Kansas.
... It breaks with wavy, irregular fracture and commonly occurs in beds about 7 inches but locally it is as little as 12 inches. ... Distribution--The Elmont limestone is exposed in Deep Creek valley south and east of Zeandale in Riley County, in secs 27,28,32, and 33,10 S., R. 9 E., and in secs. 5 and 6, T. 11S., R. 9 E. In several places in the last two sections enumerated, the limestone gives origin to small waterfalls in Deep Creek. Along the creek it is either faulted or slightly folded. It forms the natural ford at Pillsbury Crossing in sec. 5, T. 11 S., R. 9 E.
- ^ "Pillsbury Crossing Wildlife Area". GeoKansas. Kansas Geological Survey. Retrieved 2024-06-02.
A cliff on the northwest side of the river by the waterfall is the six- to nine-inch-thick Elmont Limestone Member of the Emporia Limestone formation. The crossing, waterfall ledge, and boulders at the bottom of the fall are also Elmont limestone, ...
Note: The thickness given here is for the remnant ledge of the waterfall. As can be seen along the shores of the crossing, the upper beds of the Elmont Limestone described by Jewett have been washed away within the channel.
Note: The boulders below the waterfall also include Tarkio Limestone.