No. 3333:

Lawrence Morely and Seafloor Spreading

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Today, a question of priority. The University of Houston presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

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The idea that continents have moved relative to each other over millions of years has been discussed since at least since 1912 when Alfred Wegener proposed the concept of continental drift. The mechanism for this movement, convection in the Earth’s mantle, was proposed by Arthur Holmes in 1929, but before WWII, evidence of this mechanism in rocks had not been recognized. After the war, observations from the oceans began to change that. But in the early 1960's, the now widely accepted theory of plate tectonics had not gained full acceptance.

In 1962, using new geophysical data, Princeton geologist Harry Hess began to shift the opinion regarding the motion of continents. Following Wegener and Holmes, Hess proposed that continents were moved about by “seafloor spreading”. In this model, convection in the mantle causes rifts in the crust, pushing continents away from each other. In early 1963, Canadian geophysicist, Lawrence Morely, had access to maps (but not the raw data) of the variation of the magnetic and bathymetric signature of the seafloor in the NW Pacific, but not the raw data which was still classified by the US Navy. Morely submitted manuscripts to Nature and later the Journal of Geophysical Research that discussed the significance of these anomalies for the movement of continents and seafloor spreading. This idea was still controversial at the time and when journal reviewers see novel ideas, they often look for reasons to discount the new, rather than fostering new debate. Both papers were rejected.

However, later in the same year, two researchers from Cambridge University, student Fredrick Vine and his professor Drummond Matthews, had a similar paper accepted in Nature. They argued that the pattern of magnetic anomalies in the middle of the Atlantic Ocean was consistent with Hess’s interpretation. That is much the same novel interpretation as Morely.

This publication by Vine and Mathews, coming from the Cambridge, in Nature, the preeminent journal of science, is regarded as one of the most important papers in the history of geology. It’s important because this marked the shifting of opinion from skepticism about continental drift to acceptance of what would become plate tectonics. This work has given credit for fully integrating data from the continents with the new geophysical data from the oceans, and providing independent evidence for wandering continents. However, if not for the vagaries of scientific publishing, another name might be associated with this idea. Morely’s papers were rejected partly because without the raw data, he could only describe his ideas qualitatively but perhaps they faced trouble because Morely worked at the Canadian Geological Survey. The CGS was then and is now a solid institution, but in the minds of the London-based editors of Nature, maybe not one with the same stature as Cambridge.

Morely went on to a distinguished career as head of geophysics at the CGS but, had the opinion of a few journal reviewers in 1963 been different, he might be better remembered as one of the pioneers of plate tectonics. Unfortunately, today Morely is not often mentioned because we cannot cite a paper that was never published.

I’m Peter Copeland, at the University of Houston, where we’re interested in the way inventive minds work.

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