Places to see Indiana geology

Paddle into the Pleistocene at Chain O' Lakes State Park

by John P. Roche, Tony Fleming, and John Hill

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If you think it has been cold this winter, consider that 14,000 years ago, in an epoch called the Pleistocene, it was so cold that a thick layer of glacial ice covered the northern half of Indiana! Temperatures were approximately 10 degrees Fahrenheit cooler then they are now, and the lower temperature caused snow in northern latitudes to build up, deeper and deeper, until it compressed under its own weight to form glacial ice sheets. These ice sheets flowed over the surface of the earth like slow-moving, crystalline rivers. The last glacier to cover northern Indiana was the Wisconsin ice sheet. In Chain O' Lakes State Park, you can see dramatic evidence of a catastrophic outburst of meltwater that marked the collapse of the ice sheet as the Pleistocene climate warmed. The park consists of eight interconnected lakes that occupy a deep, narrow gorge known as a tunnel valley. The tunnel valley formed below the glacier when torrents of meltwater were suddenly released and cut deeply into the bed. After the flow of meltwater waned, gravel and sand were deposited in tunnels below, and channels within, the melting glacier, creating an extensive system of winding, sharp-topped gravel ridges know as eskers. These eskers wind along the floor of the gorge. Continued melting of large, debris-covered ice blocks between the eskers resulted in the system of lakes for which the park is named. These "kettle" lakes, and the steep-sided eskers that meander among them, are one of the finest examples in the Midwest of a classic glacial landscape. So take a drive to Chain O' Lakes State Park, hop in a canoe at the boat launch at Long Lake, and take off on a paddling adventure into the Pleistocene.

Once you are done with your canoe trip, put on your hiking boots and head out onto the park's eleven miles of trails. As you hike along, you will see layers of sand and gravel that were deposited by streams of water running off from the melting glacier. You will also see "glacial till," gravel, rock, and other material carried in the glacial ice and deposited once the ice melted. Some of the glacial debris over which you will walk was carried all the way from Canada.

The park is open from 8 a.m. until 11 p.m. daily. If you are visiting Chain O' Lakes in the summer, you may want to end your visit with a tour of the park's nature center; the center, which is in an old school house, has nature programs, interpretive exhibits about the wildlife and history of the park, and educational activities for children. The nature center is open Memorial Day until Labor Day from 12 to 4 p.m.

This page is available as a brochure (IGS publication SPG10), which also includes a topographic map of the park area.

Visit the Indiana Department of Natural Resources Web site at http://www.in.gov/dnr/parklake/properties/park_chainolakes.html to read more about Chain O' Lakes State Park.