The Huntley Mountain Formation is a late Devonian and early Mississippian mapped bedrock unit in

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

, in the

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Description

The formation is composed of relatively soft grayish-red shale and olive-gray

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...

. It is located in north central Pennsylvania.

Haystacks

The Haystacks are enigmatic mounds of sandstone that outcrop in Loyalsock Creek south of Dushore in Sullivan County. They are a single

bed A bed is an item of furniture that is used as a place to sleep, rest, and relax. Most modern beds consist of a soft, cushioned mattress on a bed frame. The mattress rests either on a solid base, often wood slats, or a sprung base. Many beds ...

quartz Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical ...

with an undulating upper surface with up to one meter relief. The origin of the mounds is debatable.

Notable Exposures

* The type section of the formation is at Huntley Mountain in

Lycoming County, Pennsylvania Lycoming County is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 114,188. Its county seat is Williamsport. Lycoming County comprises the Williamsport metropolitan statistical area. About northwest o ...

, on the mountainside just north of the village of Waterville. * Base of the

Loyalsock Creek Loyalsock Creek is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed August 8, 2011 tributary of the West Branch Susquehanna River located chiefly in Sullivan and Lycoming counties in ...

gorge in

Worlds End State Park Worlds End State Park is a Pennsylvania state park in Sullivan County, Pennsylvania. The park, nearly surrounded by Loyalsock State Forest, is in the Loyalsock Creek valley on Pennsylvania Route 154 in Forks and Shrewsbury Townships southeast ...

* Haystacks beds, also in Loyalsock Creek

Stratigraphy

Geologist William E. Edmunds argues that the Huntley Mountain Formation is laterally equivalent to the

Rockwell Formation The Rockwell Formation is a late Devonian and early Mississippian mapped bedrock unit in West Virginia, Maryland, and Pennsylvania, in the United States. Description The Rockwell Formation was described at its type section at Rockwell Run in We ...

(originally described in

West Virginia West Virginia is a state in the Appalachian, Mid-Atlantic and Southeastern regions of the United States.The Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the B ...

) and the Spechty Kopf Formation. He proposes that the

Pocono Formation The Mississippian Pocono Formation is a mapped bedrock unit in Pennsylvania, Maryland, and West Virginia, in the United States. It is also known as the Pocono Group in Maryland and West Virginia, and the upper part of the Pocono Formation is somet ...

be reinstated as "the dominantly non-red, non-marine clastic sequence between the Catskill and

Mauch Chunk Formation The Mississippian Mauch Chunk Formation is a mapped bedrock unit in Pennsylvania, Maryland, and West Virginia. It is named for the township of Mauch Chunk, now known as borough of Jim Thorpe, Pennsylvania and for nearby Mauch Chunk Ridge where th ...

s", with the Huntley Mountain, Beckville, Burgoon, Rockwell, Mt. Carbon, and Spechty Kopf Formations demoted to the status of members of the Pocono Formation. Other workers support this interpretation.Lessing, Peter, Dean, S.L., and Kulander, B.R., 1992, Stratigraphy and structure of Meadow Branch synclinorium, West Virginia: Southeastern Geology, v. 32, no. 3, p. 166-174.

Description

Haystacks

Notable Exposures

Stratigraphy

References

See also