The Tarkio Limestone, is a Late-Carboniferous member of the Zeandale Formation in Kansas, extending into Nebraska, Iowa, and Missouri.[2][1] The unit was named for outcrops in the Tarkio Valley in northwestern Missouri, however, R.C. Moore designated a typical exposure of this unit on Mill Creek, southwest of Maple Hill, Kansas.[3] Owing to its unusual coloration, an early name for this rock was chocolate limestone.[2] This rock can be recognized by its coloration and abundant fusulinids, Triticites ventricosus, protruding from the surfaces, giving a "raspy" texture.[4]
| Tarkio Limestone | |
|---|---|
| Stratigraphic range: [1] (Virgilian stage)[2] | |
 Slumped blocks of Tarkio Limestone tumbling into Deep Creek below Pillsbury Crossing in Riley County, Kansas | |
| Type | Member |
| Unit of | Zeandale Limestone of Wabaunsee Group |
| Underlies | Wamego Shale member of Zeandale Limestone |
| Overlies | Willard Shale |
| Lithology | |
| Primary | Limestone |
| Location | |
| Region | Kansas |
| Country | United States |
| Type section | |
| Named for | Outcrops in the Tarkio Valley in northwestern Missouri |
| Named by | G.E. Condra[2] |
| Year defined | 1935 |
The Tarkio Limestone forms bold bluffs along Deep Creek in southeastern Riley County, Kansas and can be easily accessed there at Pillsbury Crossing,[3] about 30 miles (48 km) west of Maple Hill.
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 d "Geologic Unit: Tarkio". National Geologic Database. Geolex — Significant Publications. United States Geological Survey. Retrieved 2024-06-02.
- ^ a b 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. Retrieved 2024-06-02.
Distribution'--The Tarkio limestone forms a bench and bold cliff on each side of Deep Creek southeast of Zeandale and is exposed along the east-west road in sec. 29, T. 10 S., R. 9 E.; along the north-south road in the southeast part of the same section; along the cliff that crosses secs. 27, 28 and 33, T. 10 S., R. 9 E.; at Pillsbury's Crossing, ...
- ^ 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. Retrieved 2024-06-02.
Very robust fusulinids, Triticites ventricosus, stand out on weathered surfaces and impart a rasp-like appearance. Where best exposed the limestone is seen to consist of two beds, each approximately 6 feet thick.
 | This article about a specific stratigraphic formation in Kansas is a stub. You can help Wikipedia by expanding it. |
 | This article related to the Carboniferous period is a stub. You can help Wikipedia by expanding it. |