| Trenton Formation | |
|---|---|
| Stratigraphic range: Middle-Upper Ordovician | |
 Trenton Formation in Canada | |
| Type | Formation |
| Sub-units |
|
| Underlies | Collingwood Shale, Point Pleasant Formation & Scales Shale |
| Overlies | Black River & Plattin Formation |
| Lithology | |
| Primary | Limestone |
| Other | Chert |
| Location | |
| Region | Indiana, Michigan, Ohio, and Virginia[1] |
| Country |  United States Canada |
| Extent | Appalachia, Midwestern and Southeastern United States |
The Trenton Group is a geologic unit in Canada and Michigan, Ohio, New York State and Indiana, Pennsylvania, and West Virginia in the United States. It dates back to the Ordovician period.[2][3]
- ^ Paleozoic Sedimentary Successions of the Virginia Valley & Ridge and Plateau
- ^ "Trenton Limestone". Indiana Geological and Water Survey. Indiana University. Retrieved 6 July 2020.
- ^ Orton, Edward (1889). "THE TRENTON LIMESTONE AS A SOURCE OF PETROLEUM AND INFLAMMABLE GAS IN OHIO AND INDIANA, in Eighth Annual report of the United States Geological Survey to the Secretary of the Interior, 1886-1887: Part 2". USGS. pp. 547–556. Retrieved 6 July 2020.