Paleontology and geology
In the Early Cambrian, there was little tectonic activity in Virginia and sediments were deposited along the continental margin. The deposition of sand, silt, and other clastic materials was gradually replaced by the deposition of limy sediments in the warm tropical waters of the Iapetus Ocean. The North American continent straddled the equator at this time. The land surface had been eroded to near sea level and very little sand and mud were shed into the Cambrian seas. Abundant marine life has left behind a rich fossil record that includes stromatolites, trilobites, and archaeocyaths.