The Silurian in Missouri, US

Paleontology and geology

Silurian rocks are scarce in Missouri and are found only in a few scattered areas along its eastern border. Fossils of crinoids and starfish, as well as some brachiopods and trilobites, indicate that these rocks were deposited in a warm, shallow sea. Shales, probably formed in a shoreline environment, are interbedded with these marine rocks and contain fragments of early leafless plants called psilophytes. A few Silurian rocks have been recovered in drill cores from extreme northwestern Missouri. These rocks consist of thin limestones, shales, and a few dolostones.