Columbus Limestone

The Columbus Limestone is a mapped bedrock unit consisting primarily of fossiliferous limestone, and it occurs in Ohio, Pennsylvania, and Virginia in the United States, and in Ontario, Canada.

Columbus Limestone
Stratigraphic range: Devonian
Etched section of hand sample of Columbus Limestone from Kelleys Island
Typesedimentary
Unit ofOnondaga Group
Sub-unitsBellepoint, Marblehead, Tioga Ash Bed, Venice, Delhi, Klondike, East Liberty
UnderliesBass Islands Formation, Delaware Formation, and Ohio Shale
OverliesLucas Formation
Thickness0 to 105 feet[1]
Lithology
PrimaryLimestone
Othersandstone
Location
RegionCincinnati Arch of North America
ExtentOhio, Pennsylvania, Virginia, Ontario
Type section
Named forColumbus, Ohio
Named byMathur, 1859
Side view of a stromatoporoid in the Columbus Limestone at Kelleys Island.

Description

Depositional environment

The depositional environment was most likely shallow marine.

Stratigraphy

The Columbus conformably overlies the Lucas Dolomite in northeastern Ohio, and unconformably overlies other dolomite elsewhere. It unconformably underlies the Ohio Shale in northwestern Ohio and the Delaware Limestone in eastern Ohio.[2]

Its members include: Bellepoint, Marblehead, Tioga Ash Bed, Venice, Delhi, Klondike, and East Liberty.

Notable Exposures

Fossils

The Columbus Limestone contains brachiopods, trilobites, bryozoans, mollusks, corals, stromatoporoids and echinoderms (including crinoids).

Due to their mid-continent depositional environment, the fossils are almost free of deformation caused by tectonic activity common in the Appalachian Mountains.

Tabulate corals include Syringopora tabulata, Favosites hemispherica minuta, Emmonsia polymorpha, Thamnoptychia alternans, Pleurodictyum sp., and Coenites dublinensis. Rugose corals include Prismatophyllum rugosum, Hexagonaria anna, Eridophyllum seriale, Synaptophyllum simcoense, Amplexus yandelli, Zaphrenthis perovalis, Heterophrentis nitida, Cystiphylloides americanum, Odontophyllum convergens, Siphonophrentis gigantea.[4]

Brachiopods include Spirifer macrothyris and Brevispirifer gregarius (see Spiriferida). The gastropod (snail) Laevidentalhum martinei is present, as well as the crinoid Nucleocrinus verneulli.[5]

Fish fossils have been found in the East Liberty Member ("East Liberty bone bed").[6]

Goniatites have been found in the Columbus, including Werneroceras staufferi and Tornoceras eberlei.[7] Another cephalopod species is Goldringia cyclops.

Age

Relative age dating of the Columbus Limestone places it in the Early to Middle Devonian period.

Economic Uses

The Columbus has been mined for aggregate. Its Calcium carbonate content is 90% or higher.[8]

References

  1. Columbus Limestone, Mineral Resources On-Line Spatial Data, United States Geological Survey https://mrdata.usgs.gov/geology/state/sgmc-unit.php?unit=OHDc%3B0
  2. Ohio Division of Geological Survey, 1990 (rev. 2000, 2004), Generalized Column of Bedrock Units in Ohio; Ohio Department of Natural Resources, Division of Geological Survey, 1p. http://www.dnr.state.oh.us/Portals/10/pdf/stratcol.pdf Archived 2010-02-03 at the Wayback Machine
  3. Ehlers, G. M., and Stumm, E. C., 1951, Middle Devonian Columbus limestone near Ingersoll, Ontario, Canada, AAPG Bulletin; v. 35; no. 8; p. 1879-1888. August.
  4. Feldman, R.M.; Hackathorn (1996). Fossils of Ohio. Ohio Division of Geological Survey Bulletin 70. pp. 577 .
  5. http://www.fossilprep.com/archive/articles/columbus.htm retrieved 30 Jan 2010
  6. Wells, J.W., 1944, Middle Devonian bone beds of Ohio: Geological Society of America Bulletin, v. 55, no. 3, p. 273-302.
  7. Sweet, W. C., and Miller, A. K., 1956, Goniatites from the Middle Devonian Columbus Limestone of Ohio, Journal of Palaeontology, vol. 30, No. 4, p 811-817. July.
  8. GeoFacts No. 25, Ohio Department of Natural Resources, Division of Geological Survey "Archived copy" (PDF). Archived from the original (PDF) on 2011-06-06. Retrieved 2010-01-31.CS1 maint: archived copy as title (link)

See also


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