August 11-13, 2023 - A Stroll Along the Keweenaw
Our geology trip to the Keweenaw Peninsula in Michigan was an enthralling adventure through time, rocks, and stunning landscapes. Each stop along our journey unveiled a new geological treasure, from ancient gneiss to vibrant mineral deposits. Here's an account of our exploration, weaving through each site and its geological significance.
Day 1: Arrival and Twilight Exploration
Our journey began with a long drive straight to Michigan's Upper Peninsula. After a brief refueling stop in St. Ignace, where the anticipation of our trip reached its peak, we made a detour to The Bears Den in Shingleton for some pasties. Refreshed and recharged, we continued on to our accommodations in Toivola, settling in for the night.
As dusk fell, we ventured to Agate Beach on Lake Superior. The beach was shrouded in darkness, adding a sense of mystery to our search for emberlites - those pesky little rocks that glow under UV light. Despite the dim conditions, the challenge of finding these elusive glowsters among the pebbles and rocks heightened our excitement, setting the tone for the geologic discoveries ahead.
Day 2: A Journey Through Time and Rock
The next morning, we began our day with a visit to the A.E. Seaman Mineral Museum in Houghton. This museum is a veritable treasure trove of mineral specimens, showcasing the rich mineral diversity of the Keweenaw Peninsula and beyond. We were particularly captivated by the displays of native copper and other unique minerals found in the region. The museum provided a comprehensive overview of the area’s geological history, enriching our understanding and setting the stage for our upcoming explorations.
Our geological journey continued with the Quincy Mine Tour, where we ventured deep underground. The mine, a cornerstone of the Keweenaw's mining history, took us about 2,500 feet below the surface. As we descended, the cool, subterranean air contrasted with the surface warmth, and the sheer scale of the mine's tunnel system revealed the extensive efforts that once went into extracting copper. We observed native copper veins embedded in diabase rock, a direct link to the volcanic origins of the region.
After our underground adventure, we headed to CLK Elementary School in Calumet Township to explore the glacial grooves behind the school. These grooves, formed by ancient glaciers scraping across the bedrock, provided a fascinating glimpse into the glacial history of the area. We also sifted through rubble near the soccer field and nearby mine dumps, discovering native copper, amygdaloidal basalt with its distinctive gas bubbles, and prehnite, a mineral often associated with hydrothermal activity.
Our next stop took us to Bumbletown, Michigan. Here, atop Bumbletown Hill, we enjoyed eye-popping views of the surrounding landscape. Among the rocks, we found chrysocolla, a copper silicate mineral known for its vivid blue and green hues. The panoramic vistas and mineral finds at Bumbletown added a picturesque and colorful dimension to our trip.
Continuing our exploration, we visited the Cliff Mine in Mohawk, MI. This site, rich in copper deposits, allowed us to collect some intriguing specimens. The sweeping views from the mine were equally impressive, offering a panoramic perspective of the rugged Keweenaw terrain.
After a full day of rock hounding and exploration, we capped off the evening with a well-deserved dinner at Sundae in the Park in Mohawk, MI. The pizza was a delicious end to a rewarding day, fueling us for our next adventur, but the day was not over.
Our final stop of the day was Gratiot River County Park, where we spent the twilight hours on Lake Superior. Searching for agates and emberlites under the setting sun, we enjoyed the serene beauty of the lake and capped off the day with some last-minute collecting and some meditative rock skipping before calling it a night. When we got back to our accommodation, and after a little rest, we took in the beauty of a clear night with some stargazing, where we got to see the Milky Way and a bunch of meteors from the Perseids meteor shower. WE felt like we had just achieved a milestone - Geology by Day, Astronomy by Night!
Day 3: Delving Deeper into Michigan's Geologic Past
On our final day, we checked out of our accommodation and drove to Watersmeet. Here, we marveled at the Watersmeet Gneiss, an outcrop representing some of the oldest rocks in Michigan. At around 2.7 billion years old, and the oldest found specimen being about 3.8 billion years old, this ancient gneiss offers a glimpse into the early Earth, providing crucial insights into the planet’s formative processes. It was awe-inspiring to experience the ancientness of this outcrop, the realization that it was once upon a time a mountain range, and we were sitting in what would be the heart of that mountain - a true testament to the brevity of our existence in comparison.
Our journey continued to Republic, MI, where we explored Keweenawan intrusions of diabase dikes cutting through the ancient granitic gneiss. These dikes, dating back 1.1 billion years, highlight the dynamic geological processes that shaped the region, showcasing the contrast between the younger diabase and the older gneiss.
As we concluded our trip, we faced the long drive home. Like last year, we made a stop at Gateway City Garage for burgers in St. Ignace, taking them to go to maximize our travel time. Our trip to the Keweenaw Peninsula was an enriching experience, blending geological exploration with breathtaking landscapes and historical insights. Each stop offered a unique perspective on Earth's history, making our adventure both educational and exhilarating, and we can't wait to go back sometime soon because there is a lot we didn't have time to explore on our brief little expedition.