Glacial Map of North America

Mapping the glacial formation of continental North America.

This monumental wall map represents some of the earliest scientific efforts to map the continental glaciers of the Pleistocene Era. It covers North America north of 36 degrees of latitude and uses vibrant color to highlight the extent of glacial movement across different periods of time. These hues are outlined in the legend in the center-right, which also labels the symbols used to identify various geological features such as boulder trains, fossil-bearing deposits, eskers, and striae. Two insets in the lower left show the Principal Loess Distribution in the Central United States and a Glacial Map of the North Polar Hemisphere. Adjacent is a table listing the numerous data sources during the map’s creation.

It was a significant scientific endeavor, led by a committee of the Division of Geology and Geography branch of the National Research Council. Richard F. Flint was the chairman and he was supported by the Bureau of Geology and Topography, the United States Geological Survey, and other cooperating governmental organizations of the U.S. and Canada. Published in Washington D.C. by The Geological Society of America, originally in 1945, but this is the second edition, revised to 1949.

Source: History of the Map