Take a look at this map breakdown showing the ice retreat and formation of the Great Lakes over thousands of years. He also authors the Morning Report Newsletter and various other newsletters.
He's been with WDIV since Published: November 5, am. Lake Superior has the deepest point, at a depth of 1, feet. This continuous path is important for shipping because it provides direct access to the Atlantic Ocean via the St. Lawrence Seaway. Thanks to Emily Shaw , Contributing Writer, for compiling this information. Michigan has some of the most beautiful lakes in the world, and while most people reserve their love of the lake to the warm…. When most people think of home canning foods they often think of canning tomatoes or homemade salsa.
A national survey in indicated that…. A Holiday Tradition Did you get out and enjoy the Christmas light displays in your area last weekend?
The hamlet with a curious name is situated about forty minutes northwest of…. I have always loved Michigan, but each spring I remember exactly why that is. The ice sheet started forming about 2.
The last wave of Pleistocene glaciation pushed to its maximum extent between 25, and 21, years ago, plowing terminal moraines southward ahead of the glacial lobes. The Laurentide Ice Sheet is estimated to have been up to 3, ft 1, m thick in the area of the lakes and possibly more than 9, ft 3, m thick farther north. The leading-edge glacial lobes followed the easiest paths, which traced along preexisting drainages that had formed in weaker rocks exposed at the surface.
As the Laurentide Ice Sheet began its retreat about 20, years ago, glacial floods cut deeply into the exposed geology, and terminal moraines dammed the meltwater to form lakes. At times, flooding caused all the lakes to merge into single larger lakes, such as Lake Algonquin, but as lake levels stabilized, the five modern lakes took shape. These maps show the sequential formation of the Great Lakes.
Army Corps of Engineers, Detroit District Lake Superior is the largest, deepest, coldest, and clearest of the lakes, containing as much water as the other four lakes combined. Retention time for a drop of water in Lake Superior is nearly years.
The geology surrounding Lake Superior is Precambrian in age, with rocks as old as 3. The shape of Lake Superior follows the track of the 1. The rift filled with more than 5 mi 8 km of sediments as a large basin subsided along the rift zone. The lakes encircle the state of Michigan for a good reason. Many sand dunes occur along their inland slopes far from any body of water. As we cross the level lands we find they are actually terraces leading down to the Great Lakes, each terrace separated from its neighbor by a high or low steep cliff.
These lands have areas of heavy clay interspersed with stretches of water-washed sand and gravel. They were once lake beds; the ridges of gravel were beaches; the flat stratified sand and gravel plains and clay plains with a veneer of sand or gravel were fillings of old bays of ancient long-departed lakes and the deltas of rivers flowing into them. Each of these glacial lakes had a name.
The swamps of the UP are the remnants of that lake. As of 14, year ago see map below , when the retreating ice margins were well to the south of Lansing, the land sloped away from the ice , and thus water was not ponded in front of it.
Instead, meltwater streams formed, washing sediment out, away from the ice. Sand and gravel, which these streams could not carry, was laid down as outwash, in broad, flat outwash plains see the diagram above.
Source: Atlas of Michigan , ed. Lawrence M. Sommers, By 14, BP below a considerable part of the lower Peninsula had been deglaciated, and the three lobes affecting the area were more clearly separated.
Drainage continued southward to the Gulf of Mexico.
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