Coon Creek Fossils
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.
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.
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.
References
Baldwin, Mike (2003) Coon Creek Fossils. Memphis Archaeological
and Geological Society, Rockhound News ,49 (7), 1,4.
Coon Creek on the Internet,
Coon Creek logo, as Retrieved from the World Wide Web, (July 20, 2003).
Graphics
Ground Water Institute,
University of Memphis, Mississippi Embayment diagram, as Retrieved from
the World Wide Web, (May 15, 2003).
USGS:
What
is Geologic Time?, geologic time chart, as Retrieved from the World
Wide Web, (July 20, 2003).
Photos
Thomas, Donna (May 2003).
