Paleontology and geologyAlthough no rocks of Devonian age are shown on this map, small exposures do occur in several places in the north-central part of the state, as well as in the Black Hills in northeastern Wyoming. These rocks are mainly limestones, originally deposited as limy sediments on the floor of a shallow sea. Fossils of trilobites, brachiopods, corals, and other marine organisms are found in these rocks. |