A suggestion

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Then in October, i965, J. Tuzo Wilson, of the University of Toronto, and Fred Vine, of Cambridge, published a paper in which they defined an oddly isolated piece of mid-ocean ridge off the coasts of Oregon and Washington. It was the spreading center of what would eventually become known as the Juan de Fuca Plate, one of the smallest of all the crustal plates in the world. The volcanoes of the Cascades-Mt. Hood, Mt. Rainier, Mt. St. Helens, Glacier Peak-were lined up behind its flexplek huren hilversum trench. “Continental drift is one hypothesis I’ll get seasick for,” Deffeyes decided, and he signed up for a week’s use of the ship. He had no program in mind. To ask for a suggestion, he picked up a telephone and called Harry Hess. Instantly, Hess said, “Go to the ridge and dredge some rock from the axial valley. It better not be old.” Hess’s hypothesis that new seaBoor forms at ocean rises had scarcely been tested. This was before the Eltanin profile, and before the voyages of the Glomar Challenger. Hess’s immediate response to Deffeyes was to suggest a test that could have shelved his hypothesis then and there. Deffeyes went out to dredge the rock, but first he had to find the ridge, so he made a long pass with his echo sounder tracing the ¬†profile of the bottom. The ridge-axis rock, when he dredged it up, was extremely young. But what in the end interested Deffeyes at least as much was the benthic profile that had been ¬†flexplek huren rotterdam traced by the stylus of the sounder. The profile of the spreading center in the ocean bottom off Oregon seemed remarkably familiar to someone who had done his thesis field work in Nevada. It appeared to be, in miniature, a cross section of the Basin and Range. The new crust, spreading out, had broken into fault blocks and had become a microcosm of the Basin and Range, because both were expressions of the same cause. It was a microcosm, too, of the Triassic lowlands of the East two hundred and ten million years ago-Triassic Connecticut, Triassic New Jersey-with their border faults and basalt flows, their basins and ranges, gradually extending, pulling apart, to open the Atlantic. The Red Sea of today was what the Atlantic and its two sides had looked like about twenty million years after the Atlantic began to open. The Red Sea today was what the Basin and Range would probably look like at some time in the future. In December, i972, the astronaut Harrison Schmitt, riding in Apollo i7, looked down at the Red Sea and the Gulf of Aden-at a simple geometry that seemed to have been made with a jigsaw barely separating Africa and the Arabian peninsula. He told the people at Mission Control,

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