Date of Award
Bachelor of Science (BS)
This thesis discusses the geologic background and explores the properties and economic aspects of the clays of Lake Agassiz. The lake was located in the present Red River Valley, a leading farming area. The first complete study of the area was made by Warren Upham in the 1890’s.
Lake Agassiz covered an area of 110,000 square miles. It had the deltas, outlets, sand bars, islands and other features of any modern body of water of that great size. The lake was formed by the damming of glacial melt water by the glacier itself. As the ice retreated the lake adjusted and developed new outlets. It has been 10,000 years since the ice left. The lake lasted for 1,000 years.
Older till and lake sediments are found below the lake bed. Cretaceous and Paleozoic sediments are also present. The basement rock is Pre-Cambrian crystalline rocks.
The Lake Agassiz sediments can be divided into a silt unit and a clay unit. They both were tested for bloating, effervescence, and physical properties. Differential thermal analysis was used to study minerals and impurities in the clay.
The major economic importance of the clay is the prosperity it has given agriculture in the region. The lightweight aggregate field may develop a new industry for the clay. It would be of importance to the whole area if a low cost building material were developed.
Listoe, Bruce K., "Geologic and Economic Aspects of Lake Agassiz Clays" (1955). Undergraduate Theses and Senior Projects. 3.