Passages: George Shor shed light on plate tectonics

George Shor, the geophysicist whose studies of the ocean floor helped lay the foundation for the theory of tectonic plates and continental drift, died July 3 at his home in San Diego of complications following a series of strokes. He was 86.

He helped develop the nation’s fleet of ocean-going research vessels, was a principal in the abortive Project Mohole to drill a hole deep into the Earth, and played a key role in creation of the California Sea Grant program, which funds marine and coastal research.

“He mentored students ashore and at sea, but his strength was teaching people geophysics at sea,” said geologist Robert Fisher, a professor emeritus at the Scripps Institution of Oceanography, where Shor spent most of his career. A talented administrator and experimenter, if he saw something that didn’t work in either area, “he would diddle with it to make it better,” Fisher said.

Shor joined Scripps in 1953 at the beginning of what researchers have dubbed the golden age of oceanography, in which research vessels from Scripps, Columbia University, Woods Hole Oceanographic Institution and Cambridge University plied the oceans, trailing magnetometers and other sophisticated instruments to detect the overall structure of the ocean floor and anomalies beneath it. He began his work in the Gulf of Alaska, a region whose geologic history was little known, then led expeditions into the Indian Ocean.

During the International Geophysical Year in 1957 and 1958, he led expeditions to the Southeast Pacific.

His work and that of others eventually led to the conclusion that the planet’s continents reside on massive tectonic plates that are adrift on the ocean of volcanic magma far below the Earth’s surface, pulling apart in some areas to create deep trenches in the ocean and jamming together in others to create massive mountain ranges.

Near the end of his career, he coordinated the activities of Scripps’ research fleet, scheduling their voyages and allocating resources. He also helped create and served on the University-National Oceanographic Laboratory System, which coordinates operations of research ships throughout the world.