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Strategic plan targets invasive species
The Superior Daily Telegram (11/17)
Douglas County’s Land Conservation Committee is forwarding a plan to the county board that takes aim at invasive species.
Mich. Clean Marina Program: Public-private partners work together to improve water quality
Grand Rapids Environmental News Examiner (11/9)
Partners from the public and private sector in Michigan are working together in a voluntary program to improve the quality of the Great Lakes.
Researchers seek funding for wind test site in Lake Michigan
Grand Rapids Environmental News Examiner (11/7)
In a recent article in The Muskegon Chronicle, it was reported that researchers at Grand Valley State University’s Michigan Alternative and Renewable Energy Center (MAREC) cited a lack of year-around data (on wind platform testing) needed by prospective development companies.
COMMENTARY: Senate needs to pass clean energy act to help Michigan
The Grand Rapids Press (10/26)
Senate Majority Leader Harry Reid was absolutely correct with his recent proclamation about the current condition of the Great Lakes State: "The State of Michigan," Reid declared from the Senate Floor, with a copy Time Magazine in his hand, "is in trouble."
First Nation women 'walk the environmental talk'
WeNews (10/23)
Tomorrow's global day of climate activism aims for media and political attention. First Nation women have another way. Since 2003, they've walked the shoreline of a Great Lake or major river, meditating on the needs of an unborn generation.
City making big push for water school
The Business Journal (10/23)
The push is on to convince the University of Wisconsin-Milwaukee that the best location for its new School of Freshwater Sciences is near the university’s existing Great Lakes Water Institute on East Greenfield Avenue.
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
How the lakes were formed
Prehistoric glacial movements
Great Lakes system profile: Elevations and depths
How the lakes were formed
About a billion years ago, a fracture in the earth running from what is now Oklahoma to Lake Superior generated volcanic activity that almost split North America. Over a period of 20 million years, lava intermittently flowed from the fracture.
This geomorphic age created mountains covering the regions now known as northern Wisconsin and Minnesota, and the Laurentian mountains were formed in eastern Canada. Over time these mountains eroded, while occasional volcanic activity continued. Molten magma below the highlands of what is now Lake Superior spewed out to its sides, causing the highlands to sink and form a mammoth rock basin that would one day hold Lake Superior. Eventually the fracture stabilized and, over time, the rock tilted down from north to south.
The region went from fire to ice with the arrival of the glaciers, which advanced and retreated several times over the last 5 million years. During the periods of glaciation, giant sheets of ice flowed across the land, leveling mountains and carving out massive valleys. Where they encountered more resistant bedrock in the north, only the overlying layers were removed. To the south, the softer sandstones and shales were more affected. As the glaciers melted and began receding, their leading edges left behind high ridges, some of which can be seen today in the cliffs of Door County, Wisconsin, and the Bruce Peninsula in Ontario. Huge lakes formed between these ridges from the retreating ice fronts, and continually changed over time as the ice sheet moved northward.
Watch the formation of the Great Lakes! [ Flash | HTML ]
