Great Lakes
- Episode aired Mar 24, 2009
- TV-PG
- 44m
The Great Lakes region provided geologists with much of the evidence for the frequent ice ages that visited North America. But the lakes may be a rather transient feature of the continent de... Read allThe Great Lakes region provided geologists with much of the evidence for the frequent ice ages that visited North America. But the lakes may be a rather transient feature of the continent dependent upon the recurring ice ages to maintain their existence.The Great Lakes region provided geologists with much of the evidence for the frequent ice ages that visited North America. But the lakes may be a rather transient feature of the continent dependent upon the recurring ice ages to maintain their existence.