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National pour L'Exploitation de Oceans) brought into service the new deep submersible Cyana with a similar depth capability.

Associated with this shift in emphasis came an entirely different group of scientists who began pondering the very origin of the ocean floor and the role it played in global geology. In the late 1960s, geophysicists began a revolution in the Earth sciences by advancing a new theory to explain the observed structure of the ocean floor. In so doing, they began to explain the position of the continents rising out of our global sea.

Years earlier, a German meteorologist named Alfred Wegner had advanced what geophysicists at the time regarded as a poorly supported theory. He called it "continental drift" and drew his supporting evidence from the continental land masses. Fitting Africa and South America, he went on to compare their similar interlocking geological features. But unable to explain how continents could actually drift apart, he died in ridicule, and continental drift entered modern geology textbooks not as a unifying theory but as one held up to scorn. Beginning in the 1950s, however, this theory underwent a rebirth as geophysicists began to probe the ocean depths in earnest. Plunging heat-probes into the ocean floor sediments far from land, they were surprised to observe unusually high readings.

Although they were well aware of a central ridge in the middle of the Atlantic Ocean, which the Germans had mapped prior to World War II, it wasn't until after the war that they realized it was seismically active along its entire length. Drs. Bruce Heezen and Maurice Ewing of Columbia University's Lamont Geological Laboratory used the global distribution of earthquakes to propose the existence of a continuous range running through the major ocean basins of the world, which they termed simply the "Mid-Ocean Ridge." Reconnaissance dredging operations followed, which recovered basaltic rock samples along its summit indicating the presence of active volcanism. Various explanations were advanced to explain these observations but the real breakthrough came when Drs. Vine and Matthews published magnetic maps of a segment of the ridge, the Carlsberg Ridge. There for all to see was a systematic series of parallel strips of ocean floor having alternating magnetic polarities. More importantly, they were symmetrical or mirror images of one another, with the line of symmetry being the very center line or axis of the Mid-Ocean Ridge. From these observations came the theory of seafloor spreading later modified to be plate tectonics and Earth scientists "had a new game of chess to play." (P. Hurley, pers. comm.) And play they did.

The formal body of scientists grappling with this revolutionary theory had its roots in the International Council of Scientific Unions. This same body had initiated the International Geophysical Year in 1957 to 1958. By the late 1960s, this interest in plate tectonics was incorporated in the Geodynamics Project, "an international program of research on the dynamics and dynamic history of the earth with emphasis on deep-seated foundations of geological phenomena. This includes investigations related to movements and deformations, past and present, of the lithosphere, and all relevant properties of the earth's interior and especially any evidence for motions at depth." (Ballard, in press).

In late 1971, Dr. K.O. Emery received a letter from Dr. Xavier Le Pichon, a student of Dr. Maurice Ewing and a strong supporter of plate tectonics. Le Pichon had been urged to write to Dr. Emery by Dr. Charles "Chuck" Drake, who like Dr. Le Pichon, was a graduate of Lamont and Chairman of the Geodynamics Project. Dr. Drake had made an earlier dive in the Puerto Rico Trench aboard the French bathyscaph Archimede and saw its potential as a geological mapping tool.

Dr. Le Pichon, now in charge of a major new marine laboratory in Brest, France, the Centre Oceanologique de Bretagne (COB), wanted to use the Archimede and the new French submersible Cyana to investigate the Mid-Ocean Ridge. But he wanted it to be a joint program between France and the United States. He was keenly aware of Woods Hole's submersible Alvin and knew it was already proving itself as an emerging geological mapping tool. In his letter, Dr. Le Pichon briefly explained what he had in mind—a detailed mapping effort in the Mid-Atlantic Ridge Rift Valley—and asked Dr. Emery if he thought submersibles were up to the challenge and if Emery was interested in joining the program.

In the final draft of the letter sent to Dr. Le Pichon, Dr. Emery strongly supported such a program but declined to participate. Emery was a continental geologist comfortable with its submerged seaward limits, but he was not a "hard rock" geologist who wanted to venture into the Mid-Ocean Ridge. The next logical person for Le Pichon to turn to was Dr. James Heirtzler, chairman of Woods Hole's Department of Geology and Geophysics. Heirtzler was also a Lamont graduate, and although he was not a field geologist, he was a strong advocate of plate tectonics and a pioneer in the field of marine magnetics.

But before such a major program could receive the funding it required, a considerable amount of support within the Earth sciences community was required. France's new CNEXO to which Dr. Le Pichon's laboratory reported could make decisions without significant outside review or approval. This was not the case in the American system and, in particular, the National Science Foundation (NSF). Clearly, NSF was the obvious source of funding for what would eventually be called Project FAMOUS.

Working under the broad umbrella of the Geodynamics Project, Dr. Heirtzler worked with Drs. Drake, A.G. Fisher, Frank Press, and M. Talwani to organize the Mid-Atlantic Ridge Workshop with the official endorsement of the Ocean Science Committee of the National Academy of Sciences. If the program Le Pichon and Heirtzler had in mind was endorsed by the Academy, it was a strong candidate for NSF funding.



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