Silurian Period
Life in the ancient Silurian seas of Kentucky. Art copyrighted 1995 by Stephen Greb. Place cursor over animals in picture and look at the status bar at the bottom of the window for identification.
Silurian rocks are exposed at the surface in the Knobs Region, which rings the Blue Grass Region. Silurian rocks are absent in the Blue Grass, but occur below the surface in other parts of Kentucky. During most of the Silurian Kentucky was covered by shallow tropical seas. However, some very low lands may have been emergent in central Kentucky at times. All Silurian rocks found in Kentucky are marine and all the fossils are marine (sea-dwelling) invertebrates. Common Silurian fossils in Kentucky include corals (Cnidaria), bryozoans, brachiopods, trilobites, snails (gastropods), clams (pelecypods), squid-like animals (cephalopods), crinoids (Echinodermata), and microscopic animals like ostracodes and conodonts.