William Maurice Ewing was a Texas farmboy from the state’s desert panhandle. Somehow he became one of America’s greatest oceanographers. Today we remember his birthday (May 12, 1906) and remember a bit about what he did for the study of the Earth.
It was within his team that Marie Tharp and Bruce Heezen discovered the great mid-ocean rift and the idea of continental drift – redesigned as plate tectonics – began to be taken seriously. Even with their phenomenal 1955 discovery, the new theory took almost 15 years to gain (nearly) universal acceptance.
Ewing was the fourth of ten kids. The first three died – of poverty, actually – though the next seven all survived. Ewing’s father seemed to enjoy music and literature more than cow-poking and horse-trading, so the ranch suffered. But the children grew up strong-willed, motivated, and well-educated. They were apparently rather bright. All but one of Maurice Ewing’s siblings earned a university degree (several gained doctrates) and left the Texas panhandle. Ewing’s own escape was harrowing. Here is how he got to Rice University when he was 16:
“By 1922, the city of Houston was twenty years into the oil boom that Anthony Lucas started at Spindletop and the young farm lad, Maurice Ewing, had just arrived from the Texas panhandle. The final leg of his trip to university was by police escort. The police lift was the end of a long string of disasters that started when the teenager set off from the family ranch on an old motorcycle that quickly disintegrated. He hopped a railroad boxcar, but was punted and robbed by the brakeman, then by the two hobos who had been travelling with him. A sympathetic farmer and a salesman gave the boy rides, finally getting him into Houston. Broke and embarrassed by his rough appearance from the trip, he stopped a friendly constable who drove him to the Rice University campus.” ( – from The Mountain Mystery.)
Of course the fellow later known by everyone as “Doc” thrived at the university. He stayed eight years, working summers shoveling grain in prairie silos and collecting data for oil companies. He earned his PhD in refraction seismic. It was a fortunate choice – he would use it in research after he moved north to teach in Pennsylvania, then later as first director of Woods Hole Oceanography Institute, along the Hudson on the north edge of New York City. Maurice Ewing conducted the world’s first ocean seismic survey, operating the equipment aboard a recycled yacht. His goal at the time (1935) was to try to figure out what happens to the continent at ocean’s edge. Theories ranged from a quick dropoff to a gradual slope, but the answer was hidden under eroded sediments of unknown depth. It was Ewing’s seismic refraction survey off the Virginia shores that gave scientists the first data that begin to unravel the mysterious ocean floor.
Ewing sank a heavy seismic receiver, his microphone, which was attached to his ship by an insulated electric wire. Someone in another boat, 8 kilometres away, blasted dynamite in the water. At the same moment, a radio signal was broadcast to Ewing on his recording ship. The radio signal arrived immediately, but sound waves from the dynamite travelled more slowly through water, then various rock layers, working its way along rock interfaces until it echoed into the submerged microphone. Ewing recorded the sounds on a magnetic wire when they arrived.
It was expected that Ewing’s work would help geologists understand the transition from continent to ocean basin. When his work began, no one knew how far the continental shelf extended. Was there a quick transition (as geologists expected if the continents were mobile) or was there a long slope of sediments as might occur with stationary continents? A long trail of continental run-off might mean that below the sediments there was a sunken continent that had become the ocean basin, suggesting the North American continent had been sitting still forever. Ewing’s first seismic results on the seas showed a long gentle tapering slope. Ewing – who would spend most of his career opposed to the idea of continental drift – wasn’t surprised. It would years before enough data were collected to correct the initial interpretations.