Adapted from www.ohiogeology.com/portals/geosurvey/PDFs/Glacial/glacial.pdf and www.gcbl.org/explore/land/glacial-legacies
Enormous glaciers helped reshape the Ohio Valley tens of thousands of years ago. Ohio has at various times had 3/4 of its surface covered by sheets of ice as much as 1 mile thick.
This period of geologic history is referred to as the Ice Ages.
Ice Age glaciers invading Ohio formed in Canada and moved south as far as northern Kentucky. Sediment deposits are exposed only in SW Ohio in the vicinity of Cincinnati. After the last glacier retreated northward, the new tributaries of the Ohio
River, such as the Great Miami River, often followed wide valleys created by the earlier, larger rivers.
The material left by the ice sheets is a mixture of clay, sand, gravel, and boulders. Material deposited directly from the ice are unsorted and range from clay to boulders. Some of the debris was deposited as ridges parallel to the edge of the glacier, forming end moraines, which mark the position of the ice when it paused for a period of time. When the entire ice sheet receded because of melting, much of the rock material left in the ice was deposited on the surface as ground moraines. Many glacial lakes were formed in Ohio during the Ice Age.
The most extensive area of lake deposits is in northern Ohio bordering Lake Erie.
Because the glacier ice came from Canada, it carried with it rock types not normally found in
Ohio. Pebbles and boulders of these foreign rock types are called erratics. Rock collecting in areas of glacial drift may include granite, trace quantities of gold, and very rarely, diamonds.
Ohioans have made use of resources deposited or created by the glaciers, including:
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Rich agricultural soils
Surface waterways and groundwater stored in aquifers of glacial sediments
● Sand and gravel for construction
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●
Peat for use as a mulch and soil conditioner
Clays for making bricks and pottery

Adapted from www2.cincinnati.com/blogs/ourhistory/2012/01/30/glaciers-shared-cincinnatis-topography/
Greater Cincinnati owes its hills and the direction of its rivers and creeks to three glaciers that stopped just north of this area between 70,000 and 1.2 million years ago. Those glaciers are responsible for the location of Cincinnati and its neighborhoods. Had the glaciers moved through this area, Cincinnati’s primary river would run from south to north, and the landscape of
Cincinnati would be as flat as central Ohio.
The three glaciers that stopped north of Cincinnati stood hundreds of feet high. The melting of these glaciers formed rivers that carved the landscape. As the glaciers receded, they left deposits of sand and gravel that raised the floors of the deep valleys, creating hills. Some say that Cincinnati is a city of seven hills. Actually, it’s a city of three valleys: the Mill Creek, Little
Miami River and Great Miami River valleys.
Two million years ago, Ohio had a river system that flowed north and northwest. It was called the Teays River. Those prehistoric waterways in this region once flowed in valleys that were as high as the tops of today’s hills. A glacier entered Ohio 1.2 million years ago and blocked the flow of the Teays and its northerly flowing tributaries, creating a huge lake that filled the valleys.
The overflow carved new, deep channels that formed an early Ohio River.
The Little Miami and the Great Miami rivers evolved from the ancient Teays River system.
Portions of the Little Miami follow the channel of the ancient Ohio River.
In the 70,000 years since the last glacier, the Ohio River carved a deeper channel for itself.
Since Cincinnati’s founding, the layout of the rivers and creeks and the location of the hills governed where many city neighborhoods were established. Some of the first major roads in the city were constructed in side valleys created by the glaciers. Virtually all communities in the
Little Miami River, Great Miami River and Mill Creek valleys sit on glacial outwash, which are deposits from melting glaciers.
One of the negative impacts glaciers had on the modern Cincinnati region is landslides. The melting water from the glaciers and the ancient Teays River system carved the valleys, resulting in today’s steep hills and the high presence of clay in the soil which weakens the hillsides and leads to frequent landslides today.

Adapted from www.daytonhistorybooks.com/page/page/3837569.htm and http://pubs.usgs.gov/wsp/1808/report.pdf
We have glaciers to thank for Dayton’s water supply. The valley that Dayton is located in is in almost the exact center of the glacial drift. The deposit left by the melting of these glaciers consisted of gravel and sand. The Mad river valley, all the way from Dayton up to Springfield, is one great bed of this glacial drift. It was in this natural reservoir that the first residents of
Dayton found their vast water supply. The outwash deposits in the Dayton area are the sole sources of the large groundwater supplies that we have today.
Numerous till deposits are found around Dayton and some of these are very thick. They may be recognized as clay with fragments of rock throughout the clay mass. One mile east of
Germantown, the till deposits have a thickness of at least 70 feet. Limestone quarries near
Fairborn are also the result of glacial till.
The material carried forward by a glacier and left behind after the melting of the ice forms the moraine. The three divisions of the Dayton moraine represent three distinct stages in the retreat of the glacier. Each division records a period during which the glacial ice front remained almost stationary for a period of time.
Kames are hill-like accumulations of sand and gravel near the margins of the ice sheet. At a greater distance from the ice front, streams must have carried sand and mud, forming immense sand plains and mud flats, such as the large flat lands extending from Dayton down the Miami valley as far as West Carrollton and Miamisburg. The most southern division of the Dayton moraine extended beyond Germantown. This may be traced south of Dayton and east of the Miami valley to the hills east of Miamisburg and Franklin. From Franklin this moraine may be traced westward, south of Germantown, to Camden, and thence to Richmond, in Indiana.
Without glaciers, our Dayton and Cincinnati areas would have all been mostly flat, instead of having hills and valleys like it does today. Our soils would not be as rich in nutrients and our water supplies would not be as plentiful as they are today.

Glaciers Shape Ohio Reading Questions
Answer these questions on the LINED paper UNDERNEATH this sheet 
1.
How much of Ohio’s surface was covered by ice sheets?
2.
Where did the Ice Age glaciers invading Ohio start and end?
3.
The material deposited by glaciers can form several landforms. Name 3 of these landforms.
4.
Name 3 different ways Ohio has made use of resources deposited or created by glaciers.
5.
What did the melting of the 3 glaciers that stopped north of Cincinnati form?
6.
How was the Ohio River formed?
7.
What is one of the negative impacts of glaciers on the modern Cincinnati region?
Explain.
8.
What glacial feature created the Made River valley? How did this impact the first residents of Dayton?
9.
What is a moraine?
10. If the Dayton and Cincinnati areas did not have glaciers, would they be the same they are today? Explain.
Glaciers Shape Ohio Reading Questions
Answer these questions on the LINED paper UNDERNEATH this sheet 
1.
How much of Ohio’s surface was covered by ice sheets?
2.
Where did the Ice Age glaciers invading Ohio start and end?
3.
The material deposited by glaciers can form several landforms. Name 3 of these landforms.
4.
Name 3 different ways Ohio has made use of resources deposited or created by glaciers.
5.
What did the melting of the 3 glaciers that stopped north of Cincinnati form?
6.
How was the Ohio River formed?
7.
What is one of the negative impacts of glaciers on the modern Cincinnati region?
Explain.
8.
What glacial feature created the Made River valley? How did this impact the first residents of Dayton?
9.
What is a moraine?
10. If the Dayton and Cincinnati areas did not have glaciers, would they be the same they are today? Explain.

Glaciers Shape Ohio Reading Question Answer Key
1.
How much of Ohio’s surface was covered by ice sheets? a.
¾ of its surface
2.
Where did the Ice Age glaciers invading Ohio start and end? a.
Start – Canada b.
End – Northern Kentucky
3.
The material deposited by glaciers can form several landforms. Name 3 of these landforms. a.
End moraines b.
Ground moraines c.
Glacial lakes
4.
Name 3 different ways Ohio has made use of resources deposited or created by glaciers. a.
Rick agricultural soils b.
Surface waterways and groundwater stored in aquifers of glacial sediments c.
Sand and gravel for construction d.
Peat for use as a mulch and soil conditioner e.
Clays for making bricks and pottery
5.
What did the melting of the 3 glaciers that stopped north of Cincinnati form? a.
Rivers that carved the landscape
6.
How was the Ohio River formed? a.
About 1.2 million years ago, a glacier blocked the flow of the Teays and its northerly flowing tributaries, creating a huge lake that filled the valleys. The overflow carved new, deep channels that formed an early Ohio River. Since the last glacier (about 70,000 years ago), the Ohio River has carved a deeper channel for itself.
7.
What is one of the negative impacts of glaciers on the modern Cincinnati region? Explain. a.
Landslides – The melting of glaciers and the ancient Teays River system carved the valleys, resulting in today’s steep hills and high presence of clay in the soil, which weakens the hillsides and leads to frequent landslides.
8.
What glacial feature created the Made River valley? How did this impact the first residents of Dayton? a.
Glacial drift b.
Residents found their vast water supply from this.
9.
What is a moraine? a.
Material carried forward by glaciers and left behind after the melting of ice
10.If the Dayton and Cincinnati areas did not have glaciers, would they be the same they are today? Explain. a.
They would be different. The land would be flat instead of hills and valleys. The soil wouldn’t be as rich and we would have less water supply than we do today.