Seasonal Sightings
The view in Glacial Park from the top of the camelback kame. This spot is 75 feet above The view in Marengo Ridge by picnic shelter #2. This spot is on top of the terminal moraine left by Nippersink Creek valley. Imagine the glacier standing four to five times taller! the last advance of the Wisconsin glacier. Ice Cold by Education and Visitor Center Services Coordinator Kim Compton
As we deal with the onset of our own winter season, take a few on the trail up the camelback kame. Once on the top of the kame, moments to think about what this area experienced during the Ice you are 75 feet above Nippersink Creek valley. Imagine the glacier Age that existed in northeastern Illinois from about 100,000 years standing four to five times taller! ago to 14,000 years ago. While that may seem like a long time ago, Marengo Ridge Conservation Area in Marengo is another good in geologic time it is considered recent, and there is still evidence place to see glacial remnants. At the picnic shelter overlooking of glacial remnants in McHenry County’s Conservation Areas today. the open prairie, you will be on top of the terminal Marengo At the aptly named Glacial Park in Ringwood, visitors can see both moraine. This ridge was the farthest the Wisconsin glacier kettles and kames. Kettles are depressions that were formed extended and at the ice’s edge, a long pile of till was dumped, when large chunks of ice broke off from the melting glacier and which formed the moraine. From this same viewpoint, the valley got left behind, buried under or surrounded by the sand and was formed when the Kishwaukee River, once a rushing force, took gravel carried by the meltwater. As the ice melted, depending on meltwaters beyond the moraine. the kettle, some drained completely and some became different The highest point in McHenry County is found kinds of wetlands or water bodies. In Glacial Park there is a dry on the Woodstock moraine, in an area where kettle, a kettle marsh and a kettle bog. To the second furthest advance of the Wisconsin see these landforms, walk along the marsh glacier pushed till up and over the existing loop. Get a great view of the kettle marsh terminal Marengo moraine. Visit High Point from the amphitheater and see the kettle Conservation Area in Harvard, follow the trail bog as you walk along the ridge between and look for the USGS marker on the top of the marsh and bog. The dry kettle is the USGS marker at High Point. the hill. p/c dundee85 picnic area down the hill from the kettle parking lot. In most of the District’s Conservation Areas, you may also run across boulders or bigger sized rocks that seem out of place. These Take the numbered interpretive trail or the are called glacial erratics and were plucked from the land and Deerpath trail to see the kames. There are carried along with the glacial ice. Granite, sandstone, basalt and several in the park but the tallest and the more could be from as far away as Hudson Bay! one with a trail over the top is called the Glacial till of the camelback kame. camelback kame. A kame is a cone-shaped Despite the passing of thousands of years, many remnants of the or small ridge of till that was carried along with the glacier until glaciers can be seen in your local Conservation Areas. Take some a crack formed in the glacier and the till spilled out in the shape time this winter to witness the results of the forces of nature that of the crack. Till is the gravel and sand that was plucked from the shaped our region. land by the glaciers and deposited elsewhere. Gravel is noticeable
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Winter 2019-20 Sizing Up the IceEnvironmental Age Adventures When you think about the Ice Age, what comes to mind? Glaciers? Pre-historic animals? Cave men? Perhaps you just envisioned the animated movie. While we were not around to see the Ice Age first hand, we have evidence today of the incredible impact the glaciers had on our landscapes.
Glacial Blanks Using the information on the previous page, see if you can fill in the blanks with the correct glacial terms. Use the word bank below and ask your parents for help too!
•• A is created when •• Glacial deposits of sand, gravel and •• Unsorted material sediment a glacier begins to retreat and leaves rock form irregularly shaped mounds deposited from glaciers is also behind blocks of ice buried under and hills. These large mounds and known as . sand and gravel. When the ice melts hills are known as . it creates this depression in the land. •• A is a ridge-like WORD BANK •• A is a large rock buildup of glacial debris that marks glacial erratic that is carried by the glaciers and is the place where the advance of the kames kettle eventually left behind. This piece of ice sheet stopped and dropped the terminal moraine bedrock rock differs from all the other till it had been carrying. till
native rocks in the area. Answer Key: kettle; glacial erratic; kames; terminal moraine; till moraine; terminal kames; erratic; glacial kettle; Key: Answer
Evidence Today While we can’t take you back in time to see the incredible glaciers, you can come out today to Glacial Park and Marengo Ridge Conservation Areas to see Make Your Own Kettle At Home! evidence of the glaciers that came through McHenry County. In Glacial Park, glacial kames are one of the Now that you know a little more about glacial formations, most obvious features left behind by these glaciers. try this next activity at home to get an idea of the actual Climb to the top of the kames and then imagine how process that formed glacial kettles. the glaciers would have been still 4 to 5 times higher What You Need: than where you are standing! Or head out to Marengo Ridge to see the ridge that was the terminal moraine for the last ice sheet to cover the county!
A bowl, loose dry sand, an ice cube, a source of heat. Icons made by Smashicons, www.flaticon.com from and Freepik Goodware 1. Fill the bowl about halfway with loose dry sand. Try to make the sand as level as possible. 2. Partially bury an ice cube (the block of ice left behind by the glacier) in the center of the sand. 3. Put the bowl under some sort of heat source (the sun, or by a source of warmth). Watch as the ice cube (piece of glacier) starts to melt. As it melts, notice how it creates a depression in the sand. This depression would then fill with floodwaters from the glacier or from nearby floodplains.
READING CORNER Wooly Mammoth by Mick Manning and Brita Granstrom; Prehistoric World: The Ice Age by Dougal Dixon; Magic Treehouse: Sunset of the Sabertooth by Mary Pope Osborne
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Winter 2019-20