| Brallier Formation | |
| Type: | sedimentary |
| Age: | Frasnian - Famennian[1] |
| Period: | Late Devonian |
| Prilithology: | shale, sandstone |
| Namedby: | Charles Butts, 1918[2] |
| Region: | Appalachian Mountains |
| Country: | United States |
| Subunits: | Black Creek Siltstone Member,[3] Minnehaha Springs Member[4] |
| Underlies: | Greenland Gap Group and Scherr Formation |
| Overlies: | Harrell Formation |
| Thickness: | 1350 to 1800 feet in central PA |
| Extent: | Maryland, Pennsylvania, Virginia, and West Virginia |
The Devonian Brallier Formation is a mapped bedrock unit in Pennsylvania, Maryland, West Virginia, and Virginia.
The Brallier Formation was described by Charles Butts in 1918 as a fine-grained, siliceous shale with few fine-grained sandstone layers, from outcrops in central Pennsylvania. Others expanded usage of the term to rocks in other states.
The Brallier is roughly equivalent to the Scherr Formation.
The contact with the underlying Harrell Formation is generally gradational.
Hasson and Dennison reported the following fossils from outcrops of the lower Brallier at Keyser, West Virginia, Ridgeville, West Virginia, and McCoole, Maryland:[5]
Buchiola retrostriata, Paracardium doris, Pterochaenia fragilis
Type locality is at a railway station 6 miles northeast of Everett, Bedford County, Pennsylvania.[2]
A large exposure is located in Huntingdon, Pennsylvania, along the ramp from U.S. Route 22 west to Route 26 north.[6]
Another good exposure is on the Pennsylvania Railroad bed just west of Altoona, Pennsylvania.[6]
Relative age dating places the Brallier in the late Devonian.