Till and loess are well known deposits and need not be defined. It is a peculiar and anomalous relation between the two which it is proposed to describe in this paper. It is well known that the till almost universally occupies a position below the loess wherever the two are found in the same section. A few cases only have been noted where the reverse is true. Such an instance was described by McGee and Call in an account of the loess near Des Moines. Similar occurrences have been reported by other observers from central and eastern Iowa. These may all be readily explained by an advance of the ice sheet over the loess already deposited around its margin.
Proceedings of the Iowa Academy of Sciences
©1894 Iowa Academy of Science, Inc.
Todd, J. E. and Bain, H. Foster
"Interloessial Till near Sioux City, Iowa,"
Proceedings of the Iowa Academy of Science, 2(1), 20-23.
Available at: https://scholarworks.uni.edu/pias/vol2/iss1/7