Chapter 3

Fixists vs. mobilists


While many people in the field embraced plate tectonics almost at once and applied it to all parts of the world some were reluctant to change their view. “At Geodesy and GeophysicsGeodesy and GeophysicsMadingley Rise, a generous late Victorian house in north Cambridge, played a central role in the development of geophysics at the University of Cambridge. It was built in 1891 for a professor of astronomy, Hugh Frank Newall, who introduced geodesy teaching at Cambridge. In 1955, it became home to the Department of Geodesy and Geophysics; Newall’s study became the Head of Department’s office. The pleasant surroundings, away from the centre of Cambridge, fostered a lively and productive community at this, the smallest of the five major world geophysical laboratories of the 1960s. In 1980, Madingley Rise became the Bullard Laboratory, and part of the newly-formed Department of Earth Sciences. [University of Cambridge],” says McKenzie, “the marine geologists didn’t believe a word – they were all fixists, just like in the US.” Harold JeffreysHarold JeffreysHarold Jeffreys (1891–1989) was a mathematician who applied classical mechanics to astronomy and planetary science, in doing so shaping the development of geophysics in the UK. He successfully modelled the shape and strength of the Earth, used the developing field of seismology to delve into the Earth’s interior, found layers within the mantle and determined that the outer part of the Earth’s core was fluid. His work was crucial in locating earthquake origins, which later played a key role in mapping plate motions. He did not accept the idea of continental drift, and remained sceptical about plate tectonics. was an opponent of continental drift, principally because of the lack of a physical mechanism. “Harold never accepted these notions and his wife, the mathematician Bertha Swirles, used to say to him ‘Harold don’t be so silly! Of course they’re right.’ But it didn’t have any effect.” Maurice EwingMaurice EwingMaurice Ewing (1906-1974) graduated from Rice Institute (now University) in Texas and took a physics PhD there. He started to experiment with seismic surveying on land after his experiences as a summer worker for an oil prospecting company. From 1930 at Lehigh University he experimented with magnetic and seismic signals, and in 1937 he started working at sea on the Atlantis, developing methods to image beneath the ocean floor. He tried to interest oil companies in his ideas, to no avail. He went to Columbia in 1946 and from 1949 established the Lamont Geological Observatory. Despite Ewing driving the collection of so much of the data that led to the plate tectonics revolution, he himself remained unconvinced. at LamontLamontLamont Geological Observatory (now Lamont-Doherty Earth Observatory) was established by Columbia University, New York in 1949 following a gift of land by the Lamont family. Maurice Ewing was its first director and his dedication to exploration and discovery established it as a world leader in geophysics. Ewing demanded comprehensive data collection on Lamont research voyages, building a vast store of data: the Vema alone covered more than a million miles in her working life at Lamont. Despite this, Ewing and his colleague Walter Bucher did not accept the mobilist worldview of plate tectonics., despite leading perhaps the most extensive and comprehensive marine survey effort, never accepted the ideas; he died in 1974.

IMAGE REFERENCE: Harold Jeffreys, RAS Papers 113/59, Royal Astronomical Society.