Tarkio Limestone

Tarkio Limestone
Stratigraphic range: Gzhelian (Virgilian stage)
Slumped blocks of Tarkio Limestone tumbling into Deep Creek below Pillsbury Crossing in Riley County, Kansas
TypeMember
Unit ofZeandale Limestone of Wabaunsee Group
UnderliesWamego Shale member of Zeandale Limestone
OverliesWillard Shale
Lithology
PrimaryLimestone
Location
RegionKansas
CountryUnited States
Type section
Named forOutcrops in the Tarkio Valley in northwestern Missouri
Named byG.E. Condra
LocationMill Creek, Maple Hill, Kansas
Year defined1935

The Tarkio Limestone, is a Late-Carboniferous member of the Zeandale Formation in Kansas, extending into Nebraska, Iowa, and Missouri. 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. Owing to its unusual coloration, an early name for this rock was chocolate limestone. This rock can be recognized by its coloration and abundant fusulinids, Triticites ventricosus, protruding from the surfaces, giving a "raspy" texture.

The Tarkio Limestone forms bold bluffs along Deep Creek in southeastern Riley County, Kansas and can be easily accessed there at Pillsbury Crossing, about 30 miles (48 km) west of Maple Hill.

See also

References

  1. 1 2 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.
  2. 1 2 3 4 "Geologic Unit: Tarkio". National Geologic Database. Geolex — Significant Publications. United States Geological Survey. Retrieved 2024-06-02.
  3. 1 2 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, ...
  4. ↑ 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.