According to one view the pebble band on the Iowan till is the result of wind action in a marginal area during the retreat of the Iowan ice. An alternative interpretation is that the pebble band is the result chiefly of the erosion of Iowan till by running water, considerable time having been involved in its formation.
Proceedings of the Iowa Academy of Science
©1931 Iowa Academy of Science, Inc.
Kay, George F.
"Origin of the Pebble Band on Iowan Till,"
Proceedings of the Iowa Academy of Science, 38(1), 205-206.
Available at: https://scholarworks.uni.edu/pias/vol38/iss1/48