Date of Award


Degree Name

Master of Science


Geological and Environmental Sciences



First Advisor

Dr. Alan E. Kehew

Second Advisor

Dr. George Guthrie

Third Advisor

Dr. William Sauck

Access Setting

Masters Thesis-Open Access


Seven subsurface glacial diamicton units, including a paleosol, have been characterized from two borings in north-central St. Joseph County, Michigan. These units have been characterized in terms of their clay mineralogy, texture, color, and stratigraphic position. t-Tests confirm that each unit displays a significant difference in mean 7A/10A peak height ratio from all other units.

Unit 4, informally called the Gray Marker tilt has been correlated between borings in this study and to the findings of others (Gardner, 1997, Nicks, in preparation). The Newbury till described by the Indiana Geological Survey (unpublished data) may also correlate to Unit 4, raising the possibility that the Gray Marker till is regionally widespread in the subsurface.

A qualitative clay mineral analysis of the seven diamicton units revealed flaws in the technique of correlating diamictons solely on the basis of 7A/10A peak height ratios. Qualitative clay mineral analysis revealed similarities between the Coldwater Shale and Units 3a, 3b, and 4, suggesting that these units derived much of their clay mineral fraction from the Coldwater Shale. Units 5 and 6 had notably different suites of clay minerals, suggesting a source other than the Coldwater Shale.