Coon Creek fossils are estimated to be about 73 million years old. These fossils, from the Late Cretaceous Period, were laid down when the central portion of the United States was under water. Scientists theorize that the Coon Creek area was actually a shallow sand bar on the eastern edge of what is called the Mississippi Embayment. Water from the Mississippi Embayment or, what we know today as the Gulf of Mexico, actually came up onto the continent during this period of time. The bay of the Gulf of Mexico extended over west Tennessee up to southern Illinois. Little Rock, Arkansas was on the west coast and the Tennessee River was on the east coast. Memphis was under approximately 1,000 feet of water.
Mississippi Embayment
The climate of the area was semi-tropical and life flourished in this type of environment. Distributary streams drained the land. During what is thought to have been occurrences of tropical hurricanes, enormous amounts of river sediment buried plants and animals living there. This type of preservation process apparently helped to preserve fossils in the excellent condition that we find them in today.
Pterotrigonia thoracica, Tennessee State Fossil
The types of animals preserved at Coon Creek include: foraminifera, corals, bryozoans, brachiopods, worms, tusk shells, snails, clams, scallops, whelks, nautilus, sea urchins, ostracodes, crabs, lobsters, sharks, fish, turtles, and mosasaurs (an ancient sea reptile). Pictured here is the official Tennessee state fossil, Pterotrigonia thoracica, which can be found at Coon Creek. Coon Creek is famous for the abundance of different types of fossils. Fossils from over 600 species of animals have been found at Coon Creek ranging in size from microscopic to huge reptiles over 50 feet long. The large number of fossils found, the variety of those fossils and the perfect preservation of the fossils make Coon Creek one of the most important fossil sites in the United States.