First time viewers often do the taste test for salt thinking they can't possibly be lakes.
Posted on 12/21/2006 2:45:15 PM PST by blam
December 21. 2006 6:59AM
Turning back the clock 10,000 years
Scientists explore land bridge, petrified trees in Lake Huron.
PONTIAC, Mich. (AP) -- Scientists hope to learn more about what the Great Lakes' shorelines looked like about 10,000 years ago.
They explored a limestone land bridge that went from Alpena, Mich., to Goderich, Ontario -- a distance of about 125 miles -- and an underwater forest of petrified trees in Lake Huron.
The 2006 research, in which more than 500 dives were made, is the subject of a documentary film, "Great Lakes, Ancient Shores, Sinkholes." It premiered recently at the Cranbrook Institute of Arts in Bloomfield Hills, The Oakland Press reported.
Another study is planned for 2007 and should result in a second film, "Great Lakes, Ancient Shores," said Luke Clyburn, lieutenant commander of the Great Lakes Division of the U.S. Naval Sea Cadet Corps and a Great Lakes ship captain.
"What we are learning about the Great Lakes of several thousand years ago may change the way we think of this area," Clyburn said.
Clyburn and other scientists have been filming in the Great Lakes for at least 25 years.
There is a petrified forest in 40 feet of water in Lake Huron about two miles offshore from Lexington, Mich., he said. Some of the trees have been carbon-dated to indicate they are 6,980 years old.
The Straits of Mackinac, a passage between lakes Michigan and Huron, have been spanned by the Mackinac Bridge since the mid-1950s but didn't exist several thousand years ago, Clyburn said.
"Lake Michigan was much higher than Lake Huron, and the two did not join as they do today at the straits," he said. But water from Lake Michigan seeped underground toward Lake Huron and the two bodies of water eventually became connected.
Clyburn's current film focuses on a sinkhole in Lake Huron about two miles from Alpena near Middle Island. In prehistoric times, the sinkholes were on dry land. Americans Indians lived near these sinkholes because they provided water, which attracted game, he said.
First time viewers often do the taste test for salt thinking they can't possibly be lakes.
All without any action by man.
Amazing.
Reaction: It's a lake?
As one who was born and raised in Mitten-gan and now resides in suburban Chicago...
THAT's funny!
Great lakes homey ping
Did you see the article posting about the Great Lakes 10,000 years ago? Very interesting.
Thanks for the ping. A petrified forest under water is very interesting. Maybe the land in that area rebounded after the glaciers melted at the end of the last ice age and then settled down again more recently.
It still seems amazing to me that the Great Lakes drain into the Atlantic via the St. Lawrence River, instead of into the Gulf of Mexico via the Mississippi River.
Yes it's the one we're on. haha.
Lake Michigan drains a little into the Mississippi now. Engineers reversed the flow of the Chicago River & it became the Chicago ship & sanitary canal. You can guess the sanitary part.
Yes, I know about the Chicago River and ship and "sanitary" canal. The engineers didn't have to tunnel or dig very deep, so I'm amazed nature didn't do that. There is just a small rise of ground along the Great Lakes that keeps them flowing east instead of south. If there had been even one significant breach at any time since the lakes were formed, the lakes would have dug their own canal to the Mississippi, or more likely, to the Ohio River.
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