Published by the American Geophysical Union as part of the Maurice Ewing Series, Volume 1. A three day symposium was held in honor of the late Maurice Ewing at Arden House, Harriman, New York on March 28–31, 1976. The symposium is the first of a planned Maurice Ewing series of symposiums to be held biennially. The American Geophysical Union has agreed to publish the proceedings of the symposiums in a special Maurice Ewing series. This volume represents the first of the series.