The Ordovician in West Virginia, US

Paleontology and geology

In the Early Ordovician, layers of limestone and dolostone thousands of meters thick were deposited in a subtropical shallow sea in what is now West Virginia. In the Late Ordovician, the closing of the Iapetus Ocean produced a mountain building event called the Taconic Orogeny. Eventual erosion of these mountains produced a thick wedge of both marine and non-marine sandstones, siltstones, and shales. Trilobites scurried along the Ordovician sea floor, while floating colonies of graptolites drifted in the open waters. This map shows the presence of Ordovician rocks in the northeastern portion of the state.