Lake Minong facts for kids

Quick facts for kids Lake Minong
Glacial Lake Minong
Lake Minong Location in Michigan
Location	North America
Group	Great Lakes
Coordinates	47°42′N 87°30′W / 47.7°N 87.5°W / 47.7; -87.5
Lake type	former lake
Etymology	Historic Name of Isle Royale
Primary inflows	From Lake Agassiz through the Nipigon River
Primary outflows	Grand River valley in Michigan
Basin countries	Canada United States
First flooded	10,000 years before present
Residence time	1,500 years in existence
Surface elevation	450 ft (137 m)

Lake Minong was a huge ancient lake. It formed in the area where Lake Superior is today. This happened about 10,000 years ago during the last big ice age, called the Wisconsin glaciation. This was when giant glaciers covered much of North America.

Lake Minong was a "proglacial lake." This means it formed right in front of a melting glacier. The glacier acted like a dam, holding back the meltwater. This specific ice advance only covered part of Michigan's Upper Peninsula. Lake Minong was in the eastern part of the Lake Superior basin. At the same time, another large lake, Lake Duluth, was in the western part. These two lakes were separate because the glacier was still between them. As the ice melted and moved back, Lake Minong grew bigger. Around 9,800 years ago, the ice moved away from the Keweenaw Peninsula. This allowed Lake Duluth to join with Lake Minong, making it even larger.

How Lake Minong Formed and Changed

Here's a timeline showing how Lake Minong changed over thousands of years:

Early Stages: 11,400 Years Ago

Around 11,400 years ago, Lake Minong was much smaller. It only covered an area called Whitefish Bay. A huge ice sheet, called the Laurentian glacial mass, lay across the middle of the Lake Superior basin. Meanwhile, Lake Duluth existed in the lowlands near St. Louis Bay. This was on the St. Louis River.

Connecting Basins: 10,600 Years Ago

By 10,600 years ago, the giant glacier had melted and moved further north. This created a pathway between the eastern and western parts of the Lake Superior basin. This allowed the waters of Lake Duluth and Lake Minong to connect more easily.

Full Expansion: 9,500 Years Ago

About 9,500 years ago, Lake Minong grew to cover almost the entire Lake Superior basin. The front of the glacier had moved far north of the basin. At this time, Lake Minong was like a middle stop for water. Water from an even larger ancient lake, Lake Agassiz, flowed into Lake Minong. This water came through the Nipigon River valley and another valley called Aquasabong.

Modern Lake Superior Forms: 8,500 Years Ago

Around 8,500 years ago, a big change happened. The huge Lake Agassiz basin connected with another large ancient lake, Lake Ojibway. This caused their water to drain in a new direction, towards the Ottawa River. Because of this, the Lake Superior basin became the starting point for the entire Great Lakes system we know today. Lake Minong eventually became what we now call Lake Superior.