Excerpt from Glacial Geology of the Vandalia, Illinois, RegionKansan till is exposed in only a few places along the banks of the Kaskas kia River (vandalia Bridge Section, following manuscript, and fig. 4) and along Ramsey Creek (fig. It is recognized in the field by a zone of leaching below calcareous Illinoian till. The Kansan till is dark gray, compact, and slightly sandy. It averages 33 percent sand (standard deviation, or s=3), 42 percent silt and 25 percent clay for 21 analyses of 7 samples from 1 locality. The percentage of sand is intermediate between the two overlying Illinoian tills. Un weathered Kansan till is also distinguished by usually having two times as much calcite as dolomite and by a lower percentage of expandable clay minerals than the basal (smithboro) Illinoian till. (expandable clay minerals in this report include montmorillonite and mixed-layer clay minerals.) Preliminary fabric studies of Kansan till indicate that the Kansan ice sheet advanced from the north or northeast. The Kansan till in the Vandalia region is in the area of the eastern Kansan of Willman, Glass, and Frye (1963)About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.