The magnetism

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The magnetism over the centers of the ridges themselves was uniformly strong. Moving away from the ridges, the strong and weak stripes varied in width from a few kilometres to as many as eighty. Vine and Matthews, chatting over tea in Cambridge, thought of using this data to connect Harry Hess’s spreading seafloor to the time scale of paleomagnetic reversals. The match would turn out to be exact. The weaker stripes matched times when the earth’s magnetic field had been reversed, and the strong ones matched times when the magnetic pole was in the north. Moreover, the two sets of stripes-calendars, in effect, moving away from the ridge-seemed to be symmetrical. The seafloor was not only spreading. It was documenting its age. L. W. Morley, a Canadian, independently had reached the same conclusions. Vine and flexplek huren amsterdam Matthews’ paper was published in Nature in September, i963, and became salient in the development of plate tectonics. In January of the same year, Morley had submitted almost identical ideas to the editors of Nature, but they were not yet prepared to accept them, so Morley then submitted the paper in tl1e United States to the Journal of Geophysical Research, which rejected it summarily. Morley’s paper came back with a note telling him that his ideas were suitable for a cocktail party but not for a serious publication. Data confirming the Vine-Matthews hypothesis began to accumulate, nowhere more emphatically than in a magnetic profile of the seafloor made by the National Science Foundation’s ship Eltanin crossing the East Pacific Rise. The Eltanin’s data showed that the seafloor became older and older with distance from the spreading center, and with perfect symmetry for two thousand kilometres on either side. All through the nineteen-sixties, ships continued to cruise the oceans dragging magnetometers behind, and eventually computers were programmed to correlate the benthic data flexplek huren rotterdam with the surface wanderings of the ships. Potassium-argon dating had timed the earth’s magnetic reversals to apparent perfection for the last three and a half million years. Geologists at Columbia calcul<1;ted the rate of seafloor spreading for those years and then assumed the rate to have been constant through earlier time.