How the Rock Connects Us

Book excerpt: sle Royale and the Keweenaw Peninsula have a rich cultural, industrial, and mining heritage, all connected by their geologic underpinnings. This region is the result of geologic forces during two vastly different periods in time that shaped spectacular landscapes¿the largest lava flow known on Earth, stunning red cliffs of sandstone, an archipelago in the largest freshwater lake in the world, wave-tossed pebble beaches, dunes, and Lake Superior itself. This book offers a general introduction to the processes behind the diverse and globally significant geology of the Keweenaw Peninsula and Isle Royale and the relationship of that geology to human inhabitants, known as geoheritage.Humans came to North America more than 15,000 years ago when the glaciers were receding and leaving magnificent pieces of copper on the surface. Evidence from Isle Royale indicates that early people mined this area 4,500 years ago, although mining likely began here much earlier. Keweenaw copper was discovered at McCargoe Cove on Isle Royale, marking what is referred to as the North American Bronze Age. During this time, copper was traded all over NorthAmerica. Ancient pits have been discovered at dozens of sites on Isle Royale and the Keweenaw, and beautiful copper objects have been found throughout the Midwest, particularly in Wisconsin. Archaeological evidence along with a rich storytelling tradition indicates that early inhabitants had a deep understanding of the geologic landscape. Copper treasure from the Earth was a focus of human interest and marks the beginning of our geoheritage.