Wednesday, February 23, 2005
Kansas' Rich Evolutionary History Preserved in Fossil Record
At one time Kansas, like most of the Midwest, was under water. Until the land finally rose above sea level during the final years of the Late Cretaceous, the area was covered by a succession of oceans whose geologic record is preserved in the sedimentary rock that covers the Great Plains.
Kansas rocks are full of fossils. Although vertebrate fossils are common in Kansas rocks, particularly in the Niobrara Chalk of the Smoky Hills, invertebrate fossils are much more numerous.
From the Flint Hills on east, small invertebrate fossils (crinoids, corals, fusulinids, bryozoans, to name a few) are widespread in the limestones that crop out in roadcuts and stream banks. In the Smoky Hills region, the Fencepost limestone is loaded with clams, and the Niobrara Chalk also contains fossilized clams and oysters, as well as larger vertebrates, including fishes, sharks, and large swimming reptiles called mosasaurs and plesiosaurs.
You can learn more at the Oceans of Kansas website, and at here at GeoKansas.
Kansas rocks are full of fossils. Although vertebrate fossils are common in Kansas rocks, particularly in the Niobrara Chalk of the Smoky Hills, invertebrate fossils are much more numerous.
From the Flint Hills on east, small invertebrate fossils (crinoids, corals, fusulinids, bryozoans, to name a few) are widespread in the limestones that crop out in roadcuts and stream banks. In the Smoky Hills region, the Fencepost limestone is loaded with clams, and the Niobrara Chalk also contains fossilized clams and oysters, as well as larger vertebrates, including fishes, sharks, and large swimming reptiles called mosasaurs and plesiosaurs.
You can learn more at the Oceans of Kansas website, and at here at GeoKansas.
