Returning to Missouri from Northeast Ohio, we crossed a series of glacial landscapes. While the term "glacial terrain" brings to mind rivers of ice, carving mountains or calving into the sea, past glacial effects are not as evident to the casual traveler.
Having spent a week atop the glaciated region of the Appalachian Plateau, we initially dropped onto the vast Lake Plain of Northern Ohio, the product of Pleistocene glacial erosion and a post-glacial meltwater lake (Lake Warren, the much larger predecessor of Lake Erie). Angling southwestward through Northeast Indiana, we soon passed the site of The Maumee Torrent, which marked the birth of the Wabash River Valley.
The remainder of our journey was across the Glaciated Plain of the Midwest, where the Pleistocene glaciers pushed southward, flattening the terrain. As they retreated, they enriched the soil with glacial till, setting the stage for prairie ecosystems that have since given way to crop fields and cattle ranches. Of course, the massive sheets of ice also determined the course of the Ohio, Mississippi and Missouri Rivers, which now drain the central U.S., from the Rockies to the Appalachians.
