Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 41.This volume contains many of the papers presented at the Sixth International Gondwana Symposium, held at the Institute of Polar Studies, The Ohio State University, Columbus, Ohio, August 19-23, 1985. The symposium was the first held outside the Gondwanaland continents; other symposia were held in Buenos Aires, Argentina, 1967; Cape Town and Johannesburg, South Africa, 1970; Canberra, Australia, 1973; Calcutta, India, 1977; and Wellington, New Zealand, 1980.