Columbus Limestone

Columbus Limestone
Stratigraphic range: Devonian

Etched section of hand sample of Columbus Limestone from Kelleys Island
Type sedimentary
Unit of Onondaga Group
Sub-units Bellepoint, Marblehead, Tioga Ash Bed, Venice, Delhi, Klondike, East Liberty
Underlies Delaware Formation, Ohio Shale
Overlies Lucas Dolomite
Thickness 0 to 105 feet[1]
Lithology
Primary Limestone
Other sandstone
Location
Region Cincinnati Arch of North America
Extent Ohio, Pennsylvania, Virginia, Ontario
Type section
Named for Columbus, Ohio
Named by Mathur, 1859
Side view of a stromatoporoid in the Columbus Limestone at Kelleys Island.

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.

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 http://tin.er.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
  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 http://www.ohiodnr.com/portals/11/publications/pdf/geof25.pdf

See also