Geology of the Headwaters of the Big Sandy River

1. Geology of the Headwaters of the Big Sandy River from “The Virginia Headwaters of the Big Sandy River: A Story of Revitalization and Nature’s Resilience”

2. Physiographic Province • Appalachian Plateau Province or Cumberland Mountain Province

3. Age and Formation • Estimated 250 million years old, formed during the Paleozoic era • “Building” known as the AlleghenianOrogeny

5. Appalachian Plateau Province • Relatively flat and historically stable • Composed primarily of sedimentary layers • Rugged due to dendritic erosion

6. Sandstone • Clastic sedimentary rock • Tough and common • Sands deposited by seas that once covered the area • Responsible for many of the ridges in the area since it is hard to weather

7. Shale • Clastic sedimentary rock formed from clay and silt deposits • Fragile • Basis for much of the bedrock faulting during orogeny

8. Limestone • Sedimentary rock formed by shells and calcium carbonate • Various uses: decrease damage of acid rain and risk of fires in mines

9. Karst Topography • Created by groundwater that dissolves and erodes limestone beneath the surface • Forms sinkholes, springs, caves, and streams that sink underground

10. Dolomite • Sedimentary rock much like limestone, just higher in Magnesium • Magnesium commonly extracted from it • Used to make cement