A glacier is a body of ice that shows evidence of past and present glacial movement. glacier forms when snow piles up and compresses into the compact, dense state, eventually making a solid block of ice. This process can take hundreds of years. Once formed, a glacier is moved by gravity, moving slowly across the land, eroding it as it moves. Some glaciers can be as large as a continent. Glaciers this size are called continental glaciers. These large blocks of snow and ice once covered much of North America. Today, Antarctica and Greenland hold most of the world’s glaciers, but glaciers are found on every continent on earth. Thousands of years ago, glaciers were found in Minnesota, and as they retreated they left behind large amounts of glacial meltwater and various landforms that are still here today. …show more content…
A glaciation is when ice sheets extend southward. The last glaciation, the Wisconsin Glaciation, was about 75,000 years ago. The four main lobes, or extensions of the glacier’s body, in Minnesota, the Wedena, Rainy, Superior, and Des Moines glaciers, are, like all glaciers, named for their location. Together, these four lobes cover most of Minnesota and reached as far south as Iowa. The Wisconsin Glacier melted about 11,000 years ago. When glaciers move they erode the land around them often making large glacial lakes. A glacial lake is formed when a glacier creates a large hole in the ground and fills that hole, when it melts, with meltwater. In the past, there was seven glacial lakes in Minnesota. Lake Agassiz was the largest of these seven lakes, and it covered most of northeastern Minnesota. The lake was drained about 10,000 years ago by the River Warren. Today, there is still evidence of glacial lakes like Lake Agassiz. In the Red River Valley, the glacial lake left fertile soil in its place when it was