Great Lakes history is revealed in its ancient shorelines, reefs and lake levels

The state of Michigan has a rich geological history.
And the evidence of that history is still all around us. In many cases, all we need to do is look below our feet.
Or, in many cases, in the water below our feet.
Luke Clyburn, a United States Merchant Marine Captain operating the research/training vessel, the Pride of Michigan, admits he sailed the Great Lakes for years without giving second thought to what might lie below. Now, as president of the Noble Odyssey Foundation, which brings scientists and young people together to document underwater research projects, he leads efforts to document understanding of Great Lakes science and history.
“The Great Lakes cover up the history for this part of the world,” Clyburn said. “It’s underneath our shorelines that we’ll find out what happened 7,000 years ago.
“For years, I travelled the Great Lakes without giving thought to the fact that the lake levels could have been different. Once I realized that the changes were there, I really started looking and realized that there is so much that is yet to be discovered.”

At one time, before glaciers moved into the area and melted, the lakes were much, much shallower. As a result, those ancient shorelines are now several miles out into the lake. That results in the strange phenomena of seeing tree stumps sitting deep on the bottom of the lake. Many of those stumps are nearly 8,000 years old, leftovers from a region that looked nothing like it does today.
“A lot of people swim right over a tree stump and it never means a thing to them,” Clyburn added. “Until all a sudden there is a purpose for the tree stump being there, and they say, ‘Wow, this is pretty neat.’ ”
I have an interest in another part of the Great Lakes ancient history – its ancient reefs. Long before any animals even walked on land, what is now Michigan was covered by a shallow saltwater sea. Close to my parent’s retirement home in the south-central part of the Upper Peninsula, I have discovered hundreds of fossilized corals imbedded in the limestone shores of Lake Michigan. Nowadays, whenever I visit my parents, I head to that same shoreline looking for and photographing those coral fossils. But for years, just like Clyburn and his maritime travels, I walked over these fossils without even giving a second thought.
Here is my interview with Clyburn regarding Michigan’s ancient shorelines.