Paleontology and geology
During the Early Carboniferous (Mississippian),Tennessee was covered by a warm tropical sea that supported an abundance of marine life. The limestones produced from the sediments that accumulated on the seafloor are rich in fossils of bryozoans, brachiopods, and crinoids (sea lilies).
By the Late Carboniferous (Pennsylvanian), mountain building to the east (the Alleghenian Orogeny) produced highlands that shed vast quantities of clastic sediment westward into the sea, forming vast deltas. Coastal swamps formed over these deltas and tall scale trees (lycophytes), horsetail rushes, and other plants grew in abundance. Plant remains in these swampy lowlands eventually produced coal seams that have been economically important in the state’s history.