Laurentide Ice Sheet
Okay kiddo, imagine a long, long time ago there was a huge sheet of ice that covered a lot of North America. We call it the Laurentide ice sheet. The ice sheet was made up of layers and layers of ice that accumulated over a period of about 100,000 years.
The ice sheet was so big and so heavy that it caused the land beneath it to sink down. This created a huge bowl-shaped depression in the earth's crust, called a 'glacial trough'.
The ice sheet was also responsible for shaping the landscape of North America in other ways. As it moved slowly across the land, it scraped away soil and rocks, carving out valleys and leaving behind piles of debris called 'moraines'. It also created huge lakes, like Lake Agassiz, which covered an area the size of Europe!
Eventually, the climate started to warm up and the ice sheet began to melt. This happened very slowly, over thousands of years. As the ice melted, the water flowed down the glacial troughs, carving out even more valleys and creating new rivers and lakes.
Today, we can still see evidence of the Laurentide ice sheet in the landscape of North America. The Great Lakes were formed by the melting of the ice, and the St. Lawrence River was created by the outflow of meltwater from Lake Agassiz. So, even though the ice sheet is long gone, it has left a lasting impact on the land and waterways of this continent.
The ice sheet was so big and so heavy that it caused the land beneath it to sink down. This created a huge bowl-shaped depression in the earth's crust, called a 'glacial trough'.
The ice sheet was also responsible for shaping the landscape of North America in other ways. As it moved slowly across the land, it scraped away soil and rocks, carving out valleys and leaving behind piles of debris called 'moraines'. It also created huge lakes, like Lake Agassiz, which covered an area the size of Europe!
Eventually, the climate started to warm up and the ice sheet began to melt. This happened very slowly, over thousands of years. As the ice melted, the water flowed down the glacial troughs, carving out even more valleys and creating new rivers and lakes.
Today, we can still see evidence of the Laurentide ice sheet in the landscape of North America. The Great Lakes were formed by the melting of the ice, and the St. Lawrence River was created by the outflow of meltwater from Lake Agassiz. So, even though the ice sheet is long gone, it has left a lasting impact on the land and waterways of this continent.
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