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Grand Haven students participate in annual fishing event
Grand Haven Tribune (5/15)
In Michigan, Grand Haven Area Public Schools partnered with a nonprofit organization called Pursuing a Dream to give about 300 students with special needs the opportunity to fish and enjoy the outdoors.

NYPA funding aids three St. Lawrence River projects
Watertown Daily Times (5/10)
The St. Lawrence River Research and Education Fund has provided funding for three projects that support environmental education in and around the riverís ecosystem.

Lake Michigan Academy students learn from 'Salmon in School' project
MLive (5/9)
About 100 schools throughout Michigan are selected to take part in the Lake Michigan Academy program that aims to help stock local rivers and support fishing as a leisure activity.

Huron Perth students find Lake Huron threats
Blackburn News (5/1)
Nearly 60 high school students from the public and separate boards in Huron and Perth counties spent one day at the Oakwood Inn in Grand Bend, Ontario, where they were learning about the environmental threats and challenges to Lake Huron.

TEACH Calendar of Events
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

table of contents
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.

Lake Huron

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 ]


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