Carters Limestone

The Carters Limestone is a geologic formation in Tennessee. It preserves fossils dating back to the Ordovician period. The Carters contains abundant invertebrate fossils, including corals, stromatoporoids, brachiopods and bryozoans, mollusk (gastropods, bivalves and orthoconic cephalopods) and trilobites. Trace fossils also occur. The unit has several volcanic ash (bentonite) beds and is known to have isolated reef development.