In the recent description of the major physiographic provinces of Iowa (Pan-American Geologist, volume LXX, p. 39, 1936) the Loessial Hills belt and the Dividal Upland division were represented as reaching quite to the Missouri boundary, in the southwestern quarter of our state. Notwithstanding the circumstance that this is quite so, there is yet obvious diminishing force of the two provinces mentioned towards the extreme south. The area south of the Reel Oak fault is very noticeably flattened and hollowed, and is occupied in the down-throw depression by little resistant shales. This shallow basin is rimmed all about by limestone escarpments, and to a notable extent impresses its form upon the larger provincial features as to almost over-shadow them at times. The basin feature is really a continuation, from Missouri, of what Marbut long- ago defined as the Maryville lowland. And this title now seems very appropriate for the Iowa part of the physiographic province also.
Proceedings of the Iowa Academy of Science
©1939 Iowa Academy of Science, Inc.
"Extension of Maryville Lowland into Iowa,"
Proceedings of the Iowa Academy of Science, 46(1), 255-255.
Available at: https://scholarworks.uni.edu/pias/vol46/iss1/69