Organic remains in glacial drifts and interglacial deposits are relatively abundant in Iowa and serve as valuable aids for the resolution of certain Pleistocene problems. The existence of fossils in the glacial deposits was early recognized and became one of the criteria for the separation of drift sheets (McGee, 1878). In 1895 T. C. Chamberlain noted the presence of peat separating two tills in the Afton Junction-Thayer region of Union County, Iowa. The name Aftonian was applied in connection with these interglacial deposits and has become the established designation of the oldest recognized interglacial stage in North America.
Proceedings of the Iowa Academy of Science
©1952 Iowa Academy of Science, Inc.
Wilson, L. R.
"An Aftonian Plant Locality in Lee County, Iowa,"
Proceedings of the Iowa Academy of Science, 59(1), 307-321.
Available at: https://scholarworks.uni.edu/pias/vol59/iss1/37