Everton Formation
Stratigraphic range: Middle Ordovician
Collapse breccia (Everton Formation; Arkansas)
TypeFormation
Unit ofnone
Sub-unitsCalico Rock Sandstone Member, Jasper Limestone Member, Kings River Sandstone Member, Newton Sandstone Member, Sneeds Limestone Lentil
UnderliesSt. Peter Sandstone
OverliesPowell Formation
Thickness300 to 650 feet
Lithology
PrimaryLimestone, dolomite, sandstone
OtherShale, conglomerate, chert
Location
RegionArkansas and Illinois
CountryUnited States
Type section
Named forEverton, Boone County, Arkansas[1]
Named byEdward Oscar Ulrich

The Everton Formation is a geologic formation in northern Arkansas that dates to the middle Ordovician Period.[2] Unconformities separate this formation from the underlying Powell Formation and the overlying St. Peter Sandstone Formation. Named for the town of Everton in Boone County, Arkansas in 1907, the Everton Formation is composed primarily of dolomite, limestone, and sandstone.

Stratigraphy

Five named members of the Everton Formation are recognized (in stratigraphic order):

  • Jasper Limestone Member
  • Newton Sandstone Member
  • Calico Rock Sandstone Member
  • Kings River Sandstone Member
  • Sneeds Limestone Lentil

See also

References

  1. Purdue, A.H. (1907). "Cave-sandstone deposits of the southern Ozarks". Geological Society of America Bulletin. 18 (1): 251–256. doi:10.1130/gsab-18-251.
  2. "Everton Formation, Arkansas Geologic Survey, Ozark Plateaus, Ordovician". Archived from the original on 2014-07-14. Retrieved 2014-07-11.


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