Robert S. Dietz

Robert Sinclair Dietz was an American marine scientist who lived from 1914 to 1995 and made pioneering contributions to plate tectonics and impact crater research, working with the United States Coast and Geodetic Survey and holding positions at the Scripps Institution of Oceanography and Arizona State University. Alongside Harry Hammond Hess he conducted pioneering research on seafloor spreading published as early as 1960 and 1961, developing the idea, after observing the Emperor seamount chain and discussing it with colleague Robert Fisher in 1953, that oceanic features are transported like a conveyor belt. Later in his career he turned to meteorite impacts, becoming the first scientist to recognize the Sudbury Basin as an ancient impact structure, identifying numerous other impact craters, and promoting the use of shatter cones as diagnostic evidence of ancient impact events. His honors included the Walter H. Bucher Medal in 1971, the Francis P. Shepard Medal in 1979 and the Barringer Medal in 1985, and minor planet 4666 Dietz is named in his honor. He received the Penrose Medal in 1988.