| 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 | |
| Named for | Columbus, Ohio |
| Named by | Mathur, 1859 |
| Region | Cincinnati Arch of North America |
| Extent | Ohio, Pennsylvania, Virginia, Ontario |
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.
Contents |
The depositional environment was most likely shallow marine.
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.
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.
Brachiopods include Spirifer macrothyris and Brevispirifer gregarius (see Spiriferida). The gastropod (snail) Laevidentalhum martinei is present, as well as the crinoid Nucleocrinus verneulli.[4]
Fish fossils have been found in the East Liberty Member ("East Liberty bone bed").[5]
Goniatites have been found in the Columbus, including Werneroceras staufferi and Tornoceras eberlei.[6] Another cephalopod species is Goldringia cyclops.
Relative age dating of the Columbus Limestone places it in the Early to Middle Devonian period.
The Columbus has been mined for aggregate. Its Calcium carbonate content is 90% or higher.[7]