Great Lakes Geography

The state of Michigan is surrounded by the Great Lakes, the largest bodies of fresh water. We are so lucky to have the lakes around us. Michigan was shaped thousands of years ago and what we have now is the cause of many glaciers, rivers and lakes, and human made alterations. The Great Lakes began to form in the last glacier period about 14,000 years ago, since then they have been a big part of transportation, trade and growth for our country. (https://www.google.com/search?q=areas+and+volumes+of+the+great+lakes)
How is the majority of the fresh water for the United States in these five lakes, you may ask? Well each of these lakes can hold a large amount of water and all together they hold about 6 quadrillion gallons of water with a total
surface area of 95,160 square miles. That is a lot of area and a whole lot of water. (Zimmerman, 2013) “It has been estimated that the conditions of shaping the Great Lakes was laid from 1.1 billion years ago, when two fused tectonic plates split apart and created the Midcontinent Rift, which crossed the Great Lakes Tectonic Zone. A valley was formed providing a basin that eventually became modern day Lake Superior. When a second fault line, the Saint Lawrence rift, formed approximately 570 million years ago, the basis for Lakes Ontario and Erie were created, along with what would become the Saint Lawrence River.
The Great Lakes are estimated to have been formed at the end of the last glacial period (the Wisconsin glaciation ended 10,000 to 12,000 years ago), when the Lauren tide ice sheet receded.
The retreat of the ice sheet left behind a large amount of meltwater (see Lake Algonquin and Lake Chicago) that filled up the basins that the glaciers had carved, thus creating the Great Lakes as we know them today. Because of the uneven nature of glacier erosion, some higher hills became Great Lakes islands. The Niagara Escarpment follows the contour of the Great Lakes between New York and Wisconsin. See also Glacial Lake Iroquois and Champlain Sea. Land below the glaciers "rebounded" as it was uncovered. Because the glaciers covered some areas longer than others, this glacial rebound occurred at different rates.” (Wikipedia,
2107) The Great Lakes are the largest fresh water system on Earth and make up about 20 percent of the world’s fresh water supply and about 95 percent of the United States supply. The lakes are a major component to the lives of millions of people and provide breeding, nesting and migrating areas for many waterfowl, migrating birds and colonial birds. Along with being a home for many, the Great Lakes have been used for a lot of transportation. The lakes are connected by the Great Lakes Waterway and connected to the Atlantic Ocean by the Saint Lawrence Seaway. These lakes have provided transportation of large objects. (https://www.google.com/search?q=great+lakes&espv) The Great Lakes are related to earth system science by the NGS Great Lakes Strategical Plan. In that plan it explains how the Great Lakes connect to other system and the key points of scientific problems. Some points are; ecological health and integrity, sustainable development, human health, natural hazards and risks and scientific information transfer. Scientists go through each of the main points and get into greater detail in what has to be done to help that problem. Hundreds of years of marine activity was a large impact of the rock where Michigan now is, the surface and the state outline was formed many years later by the glacial epoch. An epoch is a period of time, so the glacial epoch was the time period of the glaciers. The rocks in the Great Lakes varies because of the vast area of glaciers that formed them. “During this event, many sheets of ice in the form of glaciers gathered in the snowfields of Canada and slowly deployed over the surface of the northern half of the North American continent burying its surface to an average depth of over 6,000 feet” (Wilson, 2017). The glaciers were the defining feature to make Michigan an outlined state. There were five different invasions of glaciers over time, the Nebraskan, Kansan, Illinonan, Ionan, and the Wisconsin. Each of these invasions caused erosion and deposition all over in Michigan. The area where Michigan is now was covered by a 1 kilometer thick glacier. When the glacier started to melt there were many large depressions in the ground that got filled with water. These areas formed the basic shape of the Great Lakes and about 10,000 years ago the Great Lakes looked like they do today.

(https://www.google.com/search?q=glaciers+in+michigan) This picture shows the location of the glaciers and where they deposited minerals and rocks. It also shows the direction of the ice and how it mainly went to the southwest. The ELPC has been focused on the water in The United States for years. With the rivers and lakes they have done many things to support them and keep them up and running. They have been reducing runoff from the rural and urban sources. With the runoff it pollutes the waterways with extra nitrogen, phosphorus and other material that cause the majority of water quality problems. Things get polluted into the rivers and streams and eventually end up into the Gulf of Mexico and keep polluting from there. They also challenge bad permits and enforce permits to power plants and wastewater treatment facilities. The ELPC is the waterways greatest friend, they are there to make sure we have safe water and nothing messes that up. Humans do a lot with the Great Lakes. There are many places to get great fish, swimming areas and using them for the fresh water they entail. We built a bridge over the Great Lakes to get from the Upper Peninsula to the Lower Peninsula. I know a local family from my hometown that runs a fish market, which catch the majority of their fish from Lake Superior because it is so close to home, easily accessible and has such a large variety of delicious fish. The Great Lakes have been used for transportation and the shipment of many products to other areas.
(https://www.google.com/search?q=mackinac+bridge)
Many people spend a lot of time in the Great Lakes, they are a large area where people just like to go visit and spend some time site seeing. But with the growing communities and the growing environment the lakes have been affected by pollution. Pollution from the people around the lakes and the things that they do, the pollution is ruining our lakes and the freshness of the water. There are many groups out there trying to stop the pollution from affecting the Great Lakes and finding the best ways to do so. We are so lucky to have these large bodies of fresh water surrounding us.
The Great Lakes were formed many years ago and help shaped this wonderful state that we get to live in. Without the Great Lakes, Michigan would not be here. We look at the glaciers from the past that helped form this area, we look at how the lakes are effected by the rivers and streams connected to them and we look at the ways that we as people effect the lakes. We have to look at the ways we can stop polluting these lakes and keep them the freshest bodies of water. The Great Lakes have been a huge part of the world we live in today and will continue to be if they can stay as fresh as they
are.