116 - The Ancient Forces That Made North America

About this episode

This episode explores the geological forces that shaped North America, focusing on the Canadian Shield and the impact of glaciers on the landscape.

North America doesn't just look remarkable — it is remarkable, and not in a flag-waving way. In this episode of Buzz, Blossom & Squeak, I want to take you on a deep-time journey across the continent and show you how the landscape beneath your feet was shaped by forces that most of us never think about. This is the older history, written in rock, ice, and river — and you can read it in everything from the Great Lakes to the path of a migrating shorebird. The Canadian Shield: The Continent's Ancient Heart At the center of the story is the Canadian Shield — an enormous region of exposed ancient rock stretching across much of Canada down into northern Minnesota, Wisconsin, and Michigan. These are some of the oldest rocks on the planet, scraped bare by glaciers and dotted with the kind of lakes that make the Northwoods feel like the last frontier. That rugged, unfinished feeling you get in places like the Boundary Waters or the Upper Peninsula is not your imagination. It's geology. The Ice That Built and Destroyed The same glaciers that stripped the north bare also left behind something extraordinary: the rich, mineral-laden soil of the Midwest that now feeds a significant portion…

People in this episode

Host: Jill McKinley

Topics covered

• geology
• landscape formation
• glaciers
• ancient history
• North America
• Canadian Shield
• river systems

Keywords

• North America
• Canadian Shield
• glaciers
• geology
• landscape
• ancient rock
• Midwest soil
• river systems

Mentioned in this episode

Places: North America, Canadian Shield, Minnesota, Wisconsin, Michigan, Boundary Waters, Upper Peninsula, Iowa, Illinois, Mississippi

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