Recent inspection of airplane photograph maps of the area of the Wisconsin drift in Iowa discloses the presence of a pattern of narrow discontinuous bands in many parts. The entire map area is being studied in some detail but the pattern for Story County may now be described and some conclusions drawn. The bands are formed by alternating light and dark streaks, (Fig. 1). Each streak is only a fraction of a mile in width, so that there may be as many as thirty of them in a mile. The light and dark streaks are not continuous for any great distance, but where they prevail the pattern formed by them stands out more or less clearly on the map, and may be traced in some cases for many miles across the county. The pattern is present over about two-thirds of the area; it is generally lacking from the eastern townships. The photograph has apparently reproduced a color difference of the earth's surface which in turn may in some way be the reflection of a topographic difference too slight to be shown on the quadrangle topographic maps and too slight to be recognized on the ground.
Proceedings of the Iowa Academy of Science
©1941 Iowa Academy of Science, Inc.
Gwynne, Charles S.
"Motion of the Wisconsin Ice in Story County, Iowa,"
Proceedings of the Iowa Academy of Science, 48(1), 289-293.
Available at: https://scholarworks.uni.edu/pias/vol48/iss1/67