Cores 11 through 26 by Gary B. Dr - University of Illinois at Urbana ...

in Figure 5 indicate the approximate locations of the sampling sites. The core number, the county in whichthe core was collected, and the length of the core are recorded in Table 1.A Giddings® hydraulically operated coring device mounted on a two-ton pickup truck was used to collectall cores. A combination of unsplit and split core barrels was used, depending on conditions encounteredin the soil. The core barrel was pushed into the soil/sediment with no applied rotation. The cores werebriefly described in the field as they were collected. Each core segment, approximately two feet long, waswrapped in plastic food wrap, then overwrapped with heavy-duty aluminum foil. The cores were labeledand placed in core boxes for transport and storage.LABORATORY METHODSAt the ISGS the cores were unwrapped, trimmed to remove any smeared and/or oxidized material fromthe outer surface, and described in more detail than was possible in the field. Samples were selectedfrom the cores for chemical analysis on the basis of observable lithologic changes. Samples were dried at50C. The dried samples were then disaggregated to approximately