In the early spring of 1921 as the writer was examining the face of the bluff bounding the north side of the Des Moines valley just below the Capitol grounds he noticed, on the west side of the entrance to a ravine between Southeast 13th and 14th streets, where the State operated a small drift coal mine for some time, a section of Pleistocene material above the Coal Measures sandstone, which seemed to present features of some interest. Closer inspection showed the probable presence of two drift sheets and since the superposed evidence of successive invasions of the continental glaciers always excites curiosity it may be worthwhile to record this bit of evidence here.
Proceedings of the Iowa Academy of Science
©1921 Iowa Academy of Science, Inc.
Lees, James H.
"Some Pleistocene Exposures in Des Moines,"
Proceedings of the Iowa Academy of Science, 28(1), 59-63.
Available at: https://scholarworks.uni.edu/pias/vol28/iss1/12