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Funding milestone reached for Aquatic Research Lab expansion
The Sault Ste. Marie Evening News (6/13)
Both houses of Michiganís legislature have approved nearly $9 million in funding for an expansion of Lake Superior State Universityís successful Aquatic Research Lab (ARL).

Students dive, document Sheboygan shipwreck
Sheboygan Press (6/13)
A team of budding nautical archaeologists from East Carolina University dove below the waves of Lake Michigan to discover what treasures lay hidden on the sandy bottom.

Island living and working at Thousand Islands Biological Station in Clayton
The Syracuse Post-Standard (6/8)
Many apply, but few are chosen for the limited number of scientific research positions each year at the Thousand Islands Biological Station (TIBS). The SUNY ESF research facility is located on Governor's Island in the St. Lawrence River in Clayton, NY.

Gems emerge in eel study
The Cornwall Standard Freeholder (5/31)
In Ontario, an ongoing study of American eel habitat on the St. Lawrence River has a preeminent biology professor and masters student charting some uncharted waters in fisheries research.

Lake Superior State celebrating 30 years of salmon releases
The Associated Press (5/29)
In Michigan, the Aquatic Research Laboratory at Lake Superior State University is celebrating three decades of raising and releasing Atlantic salmon in the St. Marys River.

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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