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| Grand River Formation | |
|---|---|
| Stratigraphic range: Pennsylvanian | |
| Type | Formation |
| Underlies | Ionia Formation |
| Overlies | Saginaw Formation |
| Location | |
| Region |  Michigan |
| Country |  United States |
The Grand River Formation is a geologic formation in Michigan. It preserves fossils dating back to the Pennsylvanian period.
