BLM Leg 2 #6	Geological History
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1. What is an ice age?
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2. What climate changes can cause glaciers to form?
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3.	How do glaciers affect the transfer of energy from the Sun? What changes in weather would this cause?
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4. Evidence indicates that North America experienced an extensive ice age. Explain how the following glacial remains were created:
a) knob and kettle sloughs
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BLM Leg 2 #6	Geological History (Continued)
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b) glacial erratics and debris
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c) glacial spillways
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5. How is prairie agriculture affected by the last ice age? 
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6. When the continental ice sheet melted, many glacial lakes were formed. The largest of these was Lake Agassiz.

a) What effect did this ancient lake have on the Prairies?
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b) What has remained of Lake Agassiz?
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BLM Leg 2 #6	Geological History (Continued)
P 3 of 3

7.  a) Many strange animals that roamed the Prairies before the last ice age are now extinct. Name some of these animals?
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    b) Many animals on the Prairies survived the ice age. Name some of these animals?
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8. If the Prairies experienced another ice age, how do you think it would affect Prairie residents today?
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