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U-M divers retrieve 8,900-year-old piece of wood from Lake Huron
Annarbor.com (12/12)
University of Michigan researchers announced they have found a 5 1/2 foot long, pole-shaped piece of wood that is 8,900 years old in Lake Huron.
Internationally renowned ‘Ocean Doctor’ to speak in Grand Rapids
MLive.com (2/3)
Known as the “Ocean Doctor,” David Guggenheim will speak in Grand Rapids, Mich., about the many similarities between the threats to the oceans and to our Great Lakes.
SSC students taking part in marine science bowl
Arenac County Independent (1/31)
Teams of Michigan high school students will be heading to Ann Arbor this weekend to take part in the annual Great Lakes Bowl, a quiz event that focuses on questions about marine and freshwater systems and biology.
No aquarium for Windsor
CBC News (1/31)
Aquariums in Cleveland, Toledo, and Chicago prove to be too much competition for Windsor.
Clarkson receives $1.4 million to study contaminants in Great Lakes fish
North Country Now (1/31)
Clarkson University has received $1.4 million to monitor formerly untraceable contaminants to water supply by studying the effects on fish in each of the Great Lakes.
Great Lakes scientists educate communities; put research to work
Great Lakes Echo (1/26)
At the Lake Superior Estuarine Research Reserve, scientists study the usual Great Lakes issues – invasive species, pollution, habitat loss, and climate change. This research is then taken directly to the community, addressing local issues.
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 ]
