Use of Soil Mechanics Data in Correlation and Interpretation of Lake Agassiz Sediments

The purpose of this paper is to illustrate the value of the use of soil mechanics in geology by the correlation and interpretation of sediments from glacial Lake Agassiz on the basis of soil mechanics test data. Quantitative data on the soil mechanics properties of liquid limit, plastic limit, natural water content, relative water content, and preconsolidation stress on samples from test borings at Grand Forks and Fargo, North Dakota, and Crookston, Minnesota, are used in establishing five stratigraphic units within the lacustrine sediments. Correlation of these units among the three localities is evaluated by means of statistical correlation coefficients. In addition, profiles of preconsolidation stress indicate a period of surface drying that denotes a short interval of drainage of Lake Agassiz not heretofore reported. Thus in this case the use of soil mechanics data yields information not readily obtainable by the usual geologic methods. It is believed that soil mechanics data could be used to considerable advantage in many other geological problems.