Runcorn, S.K. (1922-1995)

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Runcorn, S.K. (1922-1995)

English geophysicist

Geophysicist S.K. Runcorn made significant contributions to the understanding of several areas within his field, including Earth's magnetism and the theory of continental drift. During the 1950s, he helped establish the discipline of paleomagnetismthe study of the intensity and direction of residual magnetization found in ancient rocks. Later, his research encompassed lunar magnetism . Runcorn published prolifically, with the publication of more than 180 papers and editing over two dozen books.

Stanley Keith Runcorn was born on November 19, 1922 in Southport, England. He was the eldest of two children born to William Henry Runcorn, a businessman, and Lily Idina Roberts Runcorn. As Runcorn related to contributor Linda Wasmer Smith in a letter, "My interest in science as a child was certainly stimulated by excellent maths and physics teaching in my grammar school." In 1941, Runcorn began studies at Gonville and Caius College of Cambridge University. He passed the tripos, or final honors examination, in mechanical sciences two years later. Runcorn earned a B.A. degree from Cambridge in 1944 and an M.A. in 1948, before transferring to Manchester University to obtain a Ph.D. in 1949. Later, he returned to Cambridge, where he received an Sc.D. degree in 1963.

Runcorn's early years at college coincided with World War II. From 1943 through 1946, he worked on radar research for the ministry of supply at Malvern. For three years afterward, he was a lecturer in physics at Manchester University. His department head there was Patrick Maynard Stuart Blackett , who won the 1948 Nobel Prize in physics. Under Blackett's leadership, Runcorn first began a long line of investigations into geomagnetism, which extended well past his move back to Cambridge as assistant director of geophysics research in 1950.

At the time, the idea was rapidly gaining currency in England that many rocks contain within them a fossilized record of the magnetic conditions under which they were formed. This is the basic assumption behind paleomagnetic research. Runcorn compared the results of tests done on rocks from Great Britain and the United States. His analysis seemed to support the hypothesis that over hundreds of millions of years the earth's magnetic poles had undergone large-scale movement, or polar wandering. However, the polar migration routes were different depending on whether the tested rocks came from Europe or North America . This suggested that the continents themselves had actually moved. Thus, Runcorn became a proponent of the theory called continental drift. Although this idea had first been put forth in 1912, it had not up to that point won widespread acceptance. It was not until the mid-1950s that Runcorn and his colleagues published convincing evidence for its existence.

Advocates of continental drift argued that the direction of magnetization within rocks from different continents would align if only the land masses were oriented differently. However, this suggestion was not immediately embraced by most scientists, partly because a physical mechanism to explain continental drift had yet to be found. By the early 1960s, though, Runcorn had proposed that, under very high temperature and pressure, rocks beneath Earth's cold, outer shellthe lithospheremight gradually "creep," or flow. The resulting upward transfer of heat by convection currents could be the force that moved continents. This idea contributed to the modern theory of plate tectonics , which posits that the earth's shell is divided into a number of rigid plates floating on a viscous underlayer.

In 1956, Runcorn accepted a post as professor and head of the physics department at King's College, part of the University of Durham. Seven years later, King's College became the University of Newcastle upon Tyne, and Runcorn was appointed head of the school of physics there, a position he held until 1988. During this period, Runcorn was also a visiting scientist or professor at several institutions around the world, including the University of California, Los Angeles and Berkeley; Dominion Observatory, Ottawa; the California Institute of Technology; the University of Miami; the Lunar Science Institute, Houston; the University of Texas, Galveston; and the University of Queensland, Australia .

By the late 1960s, Runcorn's attention had turned toward the Moon . At the time, the Moon was generally presumed to be a dead body. As early as 1962, though, Runcorn had suggested that the Moon, too, might be subject to the forces of convectionan idea that was initially rejected by most scientists. However, examination of lunar samples brought back by the Apollo missions showed that some of them were magnetized, which implied that they had been exposed to magnetic fields while they were forming. Runcorn and his colleagues concluded that the Moon had probably once possessed its own strong magnetic field , generated within an iron core.

This magnetic field seemed to have pointed in different directions at different times in lunar history. When Runcorn and his co-workers calculated the strengths and directions of this ancient magnetism, they found evidence of polar wandering. Runcorn subsequently proposed that the wandering could have been caused by the same impacts that created large basins near the Moon's equator. According to this hypothesis, the force of the impacts could have shifted the Moon's entire surface, so that regions once near the poles might have been relocated closer to the equator. However, attempts to confirm this notion have so far proved inconclusive.

Runcorn's remarkable skill as a theorist was widely recognized. In 1989, he assumed an endowed chair in the natural sciences at the University of Alaska in Fairbanks, a position he held until his death. He also received honorary degrees from universities in Utrecht, Netherlands; Ghent, Belgium; Paris; and Bergen, Norway. Among the many prestigious awards he received are the Napier Shaw Prize of Britain's Royal Meteorological Society in 1959, the John Adams Fleming Medal of the American Geophysical Union in 1983, the Gold Medal of Britain's Royal Astronomical Society in 1984, and the Wegener Medal of the European Union of Geosciences in 1987.

In addition, Runcorn was elected a fellow or member of such respected associations as the British Royal Society, the American Physical Society, the European Geophysical Society, the Royal Netherlands Academy of Science, the Indian National Science Academy, the Royal Norwegian Academy of Science and Letters, the Pontifical Academy of Science, and Academia Europaea.

Runcorn, who never married, was an aficionado of sports and the arts. Among his favorite pastimes was rugby, which he enjoyed as a participant until he was past fifty and as a spectator thereafter. In a letter to Wasmer Smith, Runcorn described himself also as an avid fan of "squash rackets and swimming, visiting art galleries, seeing opera and ballet, reading history and politics, hiking in the country, and seeing architecture in my travels." Runcorn died at the age of 73 during a lecture tour stop in San Diego, California, where he was robbed and murdered in his hotel room.

See also Continental drift theory; Magnetic field; Paleomagnetics