Early Proterozoic Rocks of the Great Lakes Region: Sudbury, Ontario, Canada to Duluth, Minnesota, U.S.A, July 1-7, 1989

Published by the American Geophysical Union as part of the Field Trip Guidebooks Series.
This guidebook was prepared for field trip T145, "Early Proterozoic Rocks of the Great Lakes Region," as part of the 28th International Geological Congress in Washington, D.C., July 9-19, 1989. Separate segments of the trip were prepared by the field trip leaders and assembled by G.B. Morey of the Minnesota Geological Survey. The Survey, Priscilla C. Grew, Director, provided editorial and cartographic assistance and undertook preparation of the camera-ready copy. Individuals from the Geological Survey of Canada, the U.S. Geological Survey, the University of Minnesota, Duluth, and Southern Illinois University also contributed their time toward the preparation of this guidebook.