A team of Earth and atmospheric scientists has found evidence that a geographic hotspot played a major role in the formation of the Great Lakes. The researchers studied models depicting the movement of the Pangea supercontinent over millions of years, including the Cape Verde hotspot, which still exists today.
The team’s study, published in Geophysical Research Letters, suggests that the hotspot allowed more land to be scooped out, making the lakes deeper than they would have been otherwise. The researchers found that the hotspot was once located directly below Lake Superior approximately 225 to 300 million years ago.
Hotspots are cracks in the mantle that allow hot material to leak upward into Earth’s middle layers, interacting with the crust in the form of volcanoes. As the supercontinent Pangea shifted above the Cape Verde hotspot, it remained in place but appeared to move relative to the land above.
The research team also found that seismic waves lined up with the continental pass over the hotspot, leaving the ground beneath more fragile and allowing ice to scrape out more soil during the last Ice Age. This led to the formation of larger and deeper lakes than would have been possible otherwise.
This new study provides insight into the geological history of the Great Lakes region and sheds light on the role of ancient hotspots in shaping our planet’s surface.
Source: https://phys.org/news/2025-01-scientists-evidence-ancient-hotspot-played.html