Columbus Limestone


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

Corals

TaxonSpeciesNotes
PrismatophyllumP. rugosum
HexagonariaH. anna
EridophyllumE. seriale
SynaptophyllumS. simcoense
AmplexusA. yandelli
ZaphrenthisZ. perovalis
HeterophrentisH. nitida
CystiphylloidesC. americanum
OdontophyllumO. convergens
SiphonophrentisS. gigantea
HadrophyllumH. dorbignyi

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.