| Orr Formation | |
| Type: | Geological formation |
| Age: | Cambrian |
| Period: | Cambrian |
| Namedfor: | Orr Ridge |
| Namedby: | Charles D. Walcott |
| Year Ts: | 1910 |
| Subunits: | Big Horse Limestone Member |
| Thickness: | 1,825 feet |
| Extent: | House Range |
The Orr Formation is a geologic formation in Utah. It preserves fossils dating back to the Cambrian period.[1]