Word: offing
(lookup in dictionary)
(lookup stats)
Dates: during 1970-1970
Sort By: most recent first
(reverse)
(2 of 3)
In 1960, the late Princeton geologist Harry Hess provided an imaginative answer to the puzzle. Refining a rough idea suggested a generation earlier, Hess proposed that the earth's mantle is really a giant convection system. Like hot air in a room, he suggested, material heated by radioactive elements...
The theory was so unorthodox and tenuous that Hess cautiously called it "geopoetry." It was soon to become geo-fact. After studying Hess's work, a 24-year-old Cambridge University graduate student, Frederick J. Vine, proposed an ingenious test. The iron in the lava from the mid-ocean...
Building the Andes. Vine's recorder provided almost instant playback. Surveying the seabed with sensitive magnetometers towed by an oceanographic vessel, he and other investigators found a zebra-striped pattern of magnetism, its direction repeatedly reversing as their ship moved farther away from the mid-ocean ridges. Seismologists quickly...
As the evidence piles up, so do the refinements of the Hess theory. Geophysicists are now convinced that the lithosphere conveyor-belt system actually consists of six separate plates that drift on top of the earth's mantle. When they collide, they can build mountains; the Andes were probably...