We spent a second day at Pictured Rocks on a cruise to view the rock formations from the water, as well as some time to relax on the beach. Students got in swimming and Camila finally found a Lake Superior agate (a first for Earth Camp – she was determined after I described them to her)!
Nest to Preques Isle State Park to view the Jacobsville Sandstone, and then find the Great Unconformity. (today was a day of famous rock outcrops – I would put The Banded Iron Formation and The Great Unconformity in top 10 well-known outcrops in the world, both are textbook examples that you will find in any Intro Geology textbook, so we love taking students to see them up close!)
And of course, got to end the day at the 1.7 billion year old peridotite that forms the Black Rock cliffs here. As a thank you to the cliffs for being such an amazing geologic formation, we jump off them into Lake Superior!
Today we visited Kitch-iti-kipi Springs – our first time stopping there for Earth Camp – and a first visit for all the staff and students. We weren’t disappointed, it was beautiful, and a great learning experience. There is a raft with a glass bottom attached to a cable that is “self-pulled”, so we powered ourselves across the spring and viewed the bottom. Crystal clear water, trout, and turbid sand at the bottom where the spring water was flowing in. Check out the video of that below.
Next it was heading north to Pictured Rocks National Lakeshore. We hiked to Miner’s Falls, then along the cliffs to get a view of the rock layers visible here from above.
We had a great day for the start of our Upper Peninsula trip. We spent a few hours in the St. Ignace library learning about Michigan glacial history from 21,000 years ago to the present. During this deglacial time, water levels of the Great Lakes fluctuated and there is evidence of these past lake levels in the land around us. We learned about Glacial Lakes Algonquin and Nipissing stages to prepare to go see the evidence on Mackinac Island in the afternoon. We also spent some time sedimentary rocks, how they form, and specifically the Michigan Basin. Students got to make their own mini Michigan Basins with Play-Doh – who doesn’t like acting like a little kid with Play-Doh again!
We split up into a few group for the bike adventure around Mackinac Island. My group did about 10.6 miles and made it to the very top of Mackinac Island. All around the island, there are prominent rock features composed of Mackinac Breccia (our students now know all about!) that are shoreline features from glacial Lake Nipissing (water level was ~50 feet above present-day Lake Huron) and glacial Lake Algonquin (water level was ~221 feet above present-day Lake Huron). And yes, because water level was so much higher, students had to bike up, up, up the island to see those glacial Lake Algonquin features!
Another great week of Earth Camp. This week was our rising 11th graders (who are Wyoming-bound next summer) traveling the upper peninsula of Michigan.
Our first stop was Mackinac Island to see old shoreline features from glacial Lakes Nipissing and Algonquin such as sea stacks, arches, caves, and the former headlands. Also covered sedimentary rocks, Michigan Basin, and the formation of the Mackinac Breccia.
Day 2 was Pictured Rocks National Lakeshore to tour the Lake Superior shoreline and see the current features being carved into the sedimentary shoreline. Always neat in geology to see a modern-day process happening, and understand the concept “the present is the key to the past”. As we toured the shoreline, we could see first-hand how a sea arch evolves into a sea stack. Then think back to yesterday and know that when we see ancient sea arches and sea stacks, we can interpret how the formed. “The present is the key to the past” – we will keep coming back to this, especially next summer as we witness active geologic processes happening in Yellowstone.
Day 3 was spent in the Marquette, MI region. Our first stop was to the banded iron formation at Jasper Knob – here we were joined by Professor Gregory Dick to learn about these rocks and how they *might* relate to the great oxygenation event. We found our way to a pillow basalt behind the local Walmart and ended the day learning about a peridotite intrusion at Presque Isle where students got to jump from the peridotite cliffs into Lake Superior.
Day 4 we drove a bit farther to Houghton Michigan to tour the Quincey Copper Mine and visit the A.E. Seaman Mineral Museum where the University of Michigan mineral collection is displayed.
Another great Earth Camp experience. I was impressed with how much the students learned, remembered from last year, and all the new activities they were game to try. Looking forward to climbing mountains with them next summer!
Today the campers went to Houghton, MI for a tour of the Quincey Copper Mine and to explore the A.E. Seaman Mineral Museum where the University of Michigan mineral collection is displayed.
While in the Marquette region, the students went to Jasper Knob to see banded iron formations – the backbone of the iron industry in Michigan. Today they saw and learned about the copper industry, another important piece of Michigan’s economic geology and one closely linked to our department. Michigan State Geologist, Douglass Houton, reported on the copper deposits in 1841 and later became the first professor the the Geology Department at The University of Michigan.
Today we moved on from the perfectly horizontal, sedimentary rock layers of Pictured Rocks National Lakeshore to the crazy, amazing, rocks a bit west near Marquette.
We started at a road cut where Forrest showed us a dolomite and schist, separated by a fault. We also walked around this area and found stromatolite fossils – stromatolites are layered mounds, columns, and sheet-like sedimentary rocks. They were originally formed by the growth of layer upon layer of cyanobacteria, a single-celled photosynthesizing microbe.
Our next stop was the banded iron formation at Jasper Knob – the hands-down favorite rock of most instructors here. The students learned about the Great Oxidation Event responsible for forming these rocks approximately 2 billion years ago!
Next stop, Presque Isle Park in Marquette to view the Jacobsville Sandstone, the “Great” unconformity between the serpentinized peridotite and the Jacobsville Sandstone, as well as search for sulfide minerals at Black Rocks cliffs.
We ended the day with sunset rock-skipping on the beach, and dinner and cake celebrating Forrest’s birthday at his house nearby.
Today we left Mackinaw City and headed north across the bridge. First stop was just north of the bridge to see the profile of Mackinac Island – the shorelines of glacial Lakes Nipissing and Algonquin were clearly visible.
Next, we headed up north to Cambrian age rocks at Tahquamenon Falls State Park and an up-close look at sandstone, cross bedding, and a conglomerate layer.
We ended the day with a boat cruise along Pictured Rocks National Lakeshore – the area we will go explore in more detail tomorrow!
Mackinac Island Profile – check out the glacial lake shorelines
Welcome back Earth Campers! This year we are expanding Earth Camp to a second summer and bringing back our students from last summer for another outdoor Earth adventure. Our first stop was Mackinac Island. We started off the day learning about sedimentary rocks, the Michigan Basin, and how the Mackinac Breccia was formed.
After that, we headed out on bikes to explore the island and find the Mackinac Breccia, as well as shoreline features from glacial Lakes Nipissing and Algonquin such as sea stacks, arches, caves, and the former headlands.
It was a great (and exhausting) day! About 10 miles of biking – the last stop was the highest point on the island – Point Lookout and Fort Holmes.
Off to Tahquamenon Falls and Pictured Rocks tomorrow.