In 1972, the Sea Scope Expedition was commissioned by Hughes Tool Company and carried out by Global Marine Development, Inc. The object was to gather detailed information on manganese nodules, including distribution, metallic content, methods of recovery, and sea floor bathymetry in noduliferous areas. Five of six planned cruise legs were successful. The resulting report is divided into three sections. Volume I presents an overview of each of the five successful cruise legs, including some of the more significant findings and events.