Indiana at 200 (1): The Ice Age Made Indiana
by Andrea Neal
Long before Indiana was Indiana, a river of ice glided across the state, bringing with it monsoon-like rains, mudflows to rival Mount St. Helens and rich sediment deposits that to this day nourish the crops that are the backbone of the Hoosier economy.
Indiana the state has been 200 years in the making. Indiana the place goes back 2 million years to a time when ice sheets blanketed the middle latitudes and shaped the landscape we know today.
Virtually all aspects of modern Indiana were “in one way or another affected by some facet of the Ice Age,” said geologist Anthony Fleming.
Consider the following:
- The rivers that attracted Native American settlements and later the pioneers, that carried flatboats filled with trade goods and powered gristmills and sawmills, are former glacial rivers that drained the melting ice sheets.
- Huge holes carved by advancing glaciers became the Great Lakes. These, along with the St. Lawrence River, linked Indiana to the Atlantic Ocean and Europe.
- Vast ice sheets deposited nutrient-rich soil and then flattened it, giving central and northern Indiana some of the nation’s most productive farmland.
- Aquifers formed during the Ice Age provide most of the water we need for household use and for industry.
To picture Indiana during the Ice Age, Hoosiers must set aside familiar images of forested wilderness and checkerboard farm fields. Instead, conjure up a massive piece of ice molding the land like a potter modeling clay and ending where the hills of southern Indiana begin. Then imagine the ice’s retreat, following by trickles then gushes of running water
Scientists believe this pattern of gliding, melting and receding ice happened at least three times in Indiana’s ancient past. It is almost entirely responsible for the landscape of the northern two-thirds of the state. The geography of southern Indiana is due to bedrock, not glaciers.
Vestiges of the Ice Age can be seen all around, from the Dunes of northern Indiana to a large granite boulder at Potato Creek State Park to central Indiana’s sandstone cliffs.
A striking example is Pine Hills Nature Preserve near Crawfordsville adjacent to Shades State Park. Glacial melt water there formed two meandering streams – Clifty and Indian creeks – which carved a deep gorge through bedrock and left four narrow ridges rising almost 100 feet. Over one ridge, the pathway is treacherous with sheer drop-off on both sides.
A short distance away, there’s a massive wall of sandstone where the two creeks meet.
It’s not the Grand Canyon, but it proves there’s more to Indiana than flat farmland. Just look around. The Ice Age formed Indiana’s landscape and our identity.
Note to readers: This is the first in a series of essays about Hoosier history that will lead up to the celebration of the state’s bicentennial in December 2016. The series will focus on the top 100 events, ideas and historical figures of Indiana, beginning with the impact of the Ice Age and ending with the legacy of the Bicentennial itself. Neal is a teacher at St. Richard’s Episcopal School in Indianapolis and adjunct scholar with the Indiana Policy Review Foundation. Contact her at firstname.lastname@example.org.
DIRECTIONS to Pine Hills Nature Preserve: From I-74 exit 34, head south on U.S. 231 to Crawfordsville; from Crawfordsville, go south on Indiana 47 to Indiana 234; go west on 234 about 10 miles to entry of Shades State Park; take the first right after the gatehouse to trail head