Great Impact Of The Great Lakes

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The Great Impact of the Great Lakes Glaciers are formed in places where there is adequate snowfall and cold temperatures; specifically, the area needs to have temperatures that are less than 32* F and more snow than is able to melt in the summer. Present-day, glaciers only form in high latitudes and high elevations. However, 14,000 years ago, during the Pleistocene Ice Age, Michigan was covered by a mile-and-half-mile deep glacier. Over thousands of years, the temperatures alternated from warm to cool, causing the glaciers to retreat and advance. As glaciers traveled this way, they took the path of least resistance. This caused the glaciers to move south from modern-day Canada, along the riverbeds that existed where the Great Lakes now…show more content…
In addition to the Great Lakes, the glacier also created kettle lakes in Michigan. These are lakes that are formed by broken-off pieces of glaciers as they move. These pieces create indents in the land, known as kettles (Glaciers: The Work of Ice). If these kettles are below the water level, a kettle lake will form. Kettle lakes can usually be identified by their irregular, wavy edges and depths (Schaetzl). One example of a kettle lake is Higgins Lake, a lake in Roscommon County, commonly used for fishing and recreation, pictured here (MSU Hydrogeology). Because much of Michigan’s bedrock is sandstone, glacial erosion led to a large prevalence of sand in Michigan, creating beaches, dunes, and wetlands. This abundance of sand has also impacted the shores. The glacial deposits of sand throughout the state are transported by the westerly winds, moving from west to east, creating dunes on the coast of Lake Michigan, but not Lake Huron. Dunes also exist somewhat inland on the west coast of Michigan, while Lake Huron’s sand is blown into the lake, creating a sandy bottom (Ettema, 2010). One of the largest dunes on Michigan’s east coast is the Sleeping bear Dunes, pictured here (Sleeping Bear Dunes). In addition to the astounding features created by the glaciers, their movement and disappearance also created an interesting interaction between the lithosphere, asthenosphere, cryosphere, and hydrosphere. Isostasy is the interaction between the stiff lithosphere and the
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