| Tully Formation | |
|---|---|
| Stratigraphic range: Devonian | |
 Tully Formation at Taughannock Falls State Park | |
| Type | Formation |
| Sub-units |
|
| Underlies | Harrell Shale/Genesee Group |
| Overlies | Hamilton Group |
| Lithology | |
| Primary | Limestone |
| Other | Shale, Siltstone, and Sandstone |
| Location | |
| Region |  Maryland New York Pennsylvania West Virginia |
| Country | United States Canada |
| Type section | |
| Named for | Tully, NY |
| Named by | Vanuxem (1839) |
The Tully Formation is a geologic unit in the Appalachian Basin. The Tully was deposited as a carbonate rich mud, in a shallow sea at the end of the Middle Devonian.[1] Outcrops for the Tully are found in New York State and Pennsylvania.[2] It is also found subsurface in western Maryland and northern West Virginia. A number of fossil remains from marine organisms maybe found in Tully out crops.
- ^ Philip H. Heckel (1963). "Depositional Environment of the Devonian Tully Limestone of Central New York: ABSTRACT". AAPG Bulletin. 47. doi:10.1306/bc7439df-16be-11d7-8645000102c1865d. ISSN 0149-1423.
- ^ Stevenson, R. E; Skinner, W. S. (1949). "The Tully Clastics of New York and Pennsylvania". Pennsylvania Academy of Science. 23: 28–33. JSTOR 44109398.