'Geologists believe the basins of the Great Lakes were scooped out by these about 20,000 years ago'
Glaciers
THE GREAT LAKES: Geologists believe the basins of the Great Lakes were scooped out by these about 20,000 years ago
Geologists believe the basins of the Great Lakes were scooped out by these about 20,000 years ago
Geologists believe the basins of the Great Lakes were scooped out by these about 20,000 years ago
THE GREAT LAKES
Glaciers
THE GREAT LAKES