| Groos Quarry Formation | |
|---|---|
| Stratigraphic range: Ordovician | |
| Type | Formation |
| Unit of | Trenton Group |
| Location | |
| Region | Michigan |
| Country | United States |
The Groos Quarry Formation is a geologic formation in Michigan. It preserves fossils dating back to the Ordovician period.
 | This article about a specific stratigraphic formation in Michigan is a stub. You can help Wikipedia by expanding it. |
