The area of West Virginia was part of a shallow sea throughout most of the Paleozoic Era. It was mildly disturbed by tectonic developments that raised mountains to its east, along the continental edge, but mainly it accepted sediments from those mountains from Cambrian time (more than 500 million years ago) into the Permian (about 270 million years ago).
The older rocks in this series are of largely marine origin: sandstone, siltstone, limestone and shale with some salt beds during Silurian time. During the Pennsylvanian and Permian, starting about 315 million years ago, a long series of coal swamps produced seams of coal across most of West Virginia. The Appalachian orogeny interrupted this situation, folding the rocks in the Valley and Ridge to their present state and raising the deep, ancient rocks of the Blue Ridge where erosion has exposed them today.
West Virginia is a major producer of coal, limestone, glass sand and sandstone. It also produces salt and clay. Learn more about the state from the West Virginia Geological and Economic Survey.
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West Virginia Geography, State Symbols & Facts
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