| Old Church Formation | |
|---|---|
| Stratigraphic range: Oligocene | |
 Xenorophid(?) Cetacean tooth from the Old Church formation of Virginia | |
| Type | Formation |
| Unit of | Chesapeake Group |
| Underlies | Calvert Formation, Popes Creek Sand |
| Overlies | Pamunkey Group, Piney Point Formation |
| Location | |
| Region | Virginia |
| Country | United States |
The Old Church Formation is a geologic formation in Virginia and possibly Maryland. It preserves fossils dating back to the Oligocene epoch of the Paleogene period. It rarely exposes on land and is under-studied. However, deposits from this period are rare and the Old Church Formation likely contains many scientifically significant taxa.