What is the name of Lake Michigan’s deepest basin?

Lake Michigan’s deepest basin is called the Chippewa Basin.

The Chippewa Basin occupies much of northern Lake Michigan and contains the lake’s maximum depth of about 281 metres. It formed through glacial erosion, as ice sheets repeatedly advanced over the region during the Pleistocene. The ice exploited older valleys and weaknesses in the bedrock, helping create the lake’s elongated deep-water form.

The basin’s name reflects the historical use of Chippewa, an English name associated with the Ojibwe people. Lake Michigan’s northern and central underwater basins are separated from shallower areas by ridges and sills that influence water circulation and habitats.

The Chippewa Basin should not be confused with Green Bay, a large arm of Lake Michigan, or with Saginaw Bay, which belongs to Lake Huron. Basin names are used by geographers and limnologists to describe the lake floor, not separate Great Lakes. Deep basins also matter to shipping, sediment studies and long-term temperature measurements.