The Geology of Ohio Under Ohio the rocks tell a fascinating story wherever you go. Northern Ohio borders Lake Erie. Eastern Ohio rises to meet mountains where coal mines tunnel into the earth. Western Ohio leads to fields of farms that look like patchwork quilts. Southern Ohio has steep cliffs and valleys carved by the winding Ohio River and ancient streams where you can find ancient caves. Did you ever wonder what is underneath Ohio?
What is Under Ohio? Rocks formed from magma. Rocks formed from fiery volcanoes that erupted when the continents pulled apart. Metamorphic rocks from mountains that formed when the continents pushed together. Sedimentary rocks from tropical seas that covered Ohio millions of years ago and left behind fossil seashells, corals and fish bones. Rocks left behind from icy-cold glaciers that spread across the land – you might even find diamonds and gold among the glacier scraped stones.
Geologic Time Scale
Geological Periods to Know Quaternary – Ice age; Great Lakes scraped out and many rocks left behind (~1.5 m yrs. ago) Mississippian & Pennsylvanian – Ohio covered in swamps, organisms left for coal to form, fossil record (~300 m yrs. Ago), when our sandstone started forming Devonian – Ohio covered in shallow seas, sediment rocks deposited, fossil record (~350 m yrs. Ago)
Geologic Cross Section of Ohio
Local Rock Formations Berea Sandstone Bedford Shale http://www.amst.com/ http://home.earthlink.net/~bereahistorical/Sandstone.html http://www.sandstonepatio.com/ Bedford Shale http://www.ohiohistorycentral.org/entry.php?rec=2857 http://www.newarkcampus.org/professional/osu/faculty/jstjohn/Bedford%20Shale/Bedford%20Shale.htm
Berea Sandstone
The Big Quarry- Berea, Ohio
Bedford Shale
Ohio’s Fossils Found only in Sedimentary Rocks! Trilobites – looks like a bug! Brachiopods – looks like a clam! Crinoids – looks like a flower! Corals – looks like modern horn coral!
Trilobites! State Fossil of Ohio
Brachiopods!
Crinoids!
Coral!
Dunkleosteus!
Dunkle Who?
Dunkleosteus!
Kuhl Things at Other Places in Ohio Kelleys Island – you can see huge, long grooves scraped into the limestone bedrock by the glaciers that moved down from Canada! Cleveland – there is a mine that goes down more than a thousand feet to a layer of rock salt; some of the mine is even under Lake Erie! Under Toledo is limestone from a tropical sea where trilobite relatives are found in the great numbers. Under Ashtabula are clay deposits from when Lake Erie was much larger than it is today.
Mrs. Draves on glacial grooves!
More Kuhl Things at Other Places in Ohio Under Campbell Hill, the highest point in Ohio (1,549 feet) the shale formed a hill so high and wide that it force the glaciers to move around it! Just north of Cincinnati, the last glacier stopped and left hills of sand and gravel. Under the city are rich fossil beds from shallow seas and can be seen from the cliffs along the Ohio river! Under Columbus are the roots of the Grenville Mountains that were once higher than the Rocky Mountains!
Credit goes to: Charles Ferguson Barker, author and illustrator of: Under Ohio The Story of Ohio’s Rocks and Fossils We used some of the information from his book in putting together this Power Point. Thanks, Charles!