Paleontology and geology
Glacial deposits from the Early Quaternary (Pleistocene) Ice Ages (not shown on this map) are common in the northern part of the state, and the melting of the glaciers greatly influenced and changed the courses of large streams such as the Kentucky and Licking Rivers. Prehistoric animals driven southward by the ice sheets were attracted to the salt and mineral springs in the swampy areas of northern Kentucky. Fossils in Big Bone Lick State Park include mastodons, mammoths, giant ground sloths, bison, elk, the short-faced bear, lions, and other mammals. Similar fossils are also found at other mineral springs and salt licks, as well in caves, sinkholes, ponds, and river gravel deposits.