The Cambrian in South Dakota, US

Paleontology and geology

A sequence of progressively finer-grained layers of sediment indicates that sea level rose across South Dakota during the Cambrian and eventually covered areas of exposed land. Although body fossils are not abundant, trace fossils are very common in the state’s Cambrian rocks. Although this map only indicates the presence of undifferentiated rocks, there are exposures of Cambrian rocks in the Black Hills region of western South Dakota.