Geological Formations in Pocahontas County--PCGS

 

The outcropping rocks of Pocahontas County, West Virginia range from the Lower Silurian to the Kanawha Group of the Pennsylvanian periods.

 

These rocks contain large quantities of coal, limestone, building stone, clays, and iron ore. The eastern half of Pocahontas County exhibits mountains formed by folding and erosion. The western half of the county shows mountain topography resulting from ages of erosion by streams. All of the rocks in Pocahontas County are sedimentary, deposited in water.

 

The most significant geological formations in Pocahontas County are described below.

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Pottsville Series: The Pottsville Series is characterized by rough and mountainous topography.

The series contains thick, massive sandstones and conglomerates. Streams cutting across these layers leave large cliffs that form the shoulders of valleys and the tops of mountains.

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Mauch Chunk Series: The Mauch Chunk Series covers about 25% of Pocahontas County and is found in the western part of the county.

It lies west of the Greenbrier Limestone belt.

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Greenbrier Series: The Stony Gap Sandstone (or Hinton Sandstone) is present in Pocahontas County and forms the base of the Greenbrier Series.

 

The Greenbrier Series is generally composed of limestone. The series contains numerous marine fossils.

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Maccrady Series: The Maccrady Series lies beneath the Pocono Series.

 

The lower portion of the Maccrady Series contains dark shales with some limestone. The upper part of the series contains red and green shales with some sandstone.

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Pocono Series: The Pocono Series is the basal subdivision of the Mississippian period in Pocahontas County.

 

This series is composed mostly of coarse reddish-brown sandstones. The series also contains gray and dark sandy shales, coal, and conglomerates. Several resistant sandstone members of the Pocono Series form the peaks of ridges and flats.

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Devonian Rocks: The Devonian period makes up more than half of the exposed rock column in Pocahontas County.

 

The rocks are limited to the eastern half of the county.

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Silurian Rocks: The Salina Series of the Silurian period is composed of blue to gray limestone that is sometimes massive.

 

The Bloomsburg Group within the Salina Series is composed of grayish-brown sandstone.

 

The source document provides a great deal of information on the specific characteristics of each of these formations. There is additional information on the geological formations of surrounding counties.

For information on specific locations of these formations within the county, refer to the maps included in the source document.