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Period: to
Mississippian Period
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Erosion
During the early part of the period, sediments were being eroded from the Acadian Mountains to the east and from the Canadian shield to the north. -
Erosion 2
Clay, silt, and fine-grained sand settled in the Ohio sea as the offshore portion of the Catskill Delta to the east -
Period: to
Tournasian Epoch
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Laurasia
Supercontinent Laurasia consisted of North American and Eurasion continents. -
Gondwana
South America, India, Australia, Africa, and Anarctica combined to make the supercontinent Gondwana -
Flooding and Reefs= calcium carbonate limestone
Low-lying parts of coninents flooded again as sea levels rose and fell.
Reef-building organisms then laid down huge deposits of calcium carbonate. They are now thick layers of limestone. -
Ice Age
Beginnning of Karoo ice age -
Trees
Large primitive trees develope. -
Rocks
Rocks consist primarily of erosion-resistant sandstones and sandy shales that form prominent cliffs -
Forests
Forests consisting of ferns, mosses, horsetails and gynosperms. -
Period: to
Visean Epoch
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"Coal Swamps"
Tropical rainforests and swamps rich with vegetation that would later become coal beds grew on exposed land, and shallow, tropical seas covered large regions of the present-day American Midwest and South. -
Oxygen
Oxygen levels increase -
Vertebrates
Vertebrates appear on land -
Insects
First winged insects appear. -
Fossils
Mississippian marbles and limestones were filled with fossils of flower-like invertebrates called crinoids, intricate corals, and other Paleozoic carbonate organisms. (Now exposed throughout the American Midwest.) -
Period: to
Serpukhiovian Epoch
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Appalachian Mountains
Collision between Africa and Eastern North American created the Appalachian mountains. -
Muddy Seas
Muddy seas persisted across the area that is now Ohio. They were not favorable for many bottom-dwelling invertebrates. Few were well preserved in these rocks.
