The Four Dimensions of the Spreading Axis
Even though Matthew Fontaine Maury had revealed the existence of the Mid-Atlantic Ridge a hundred years before, it was well past the mid-point of the present century before the reality and great extent of the global mid-ocean ridge system became impressed upon the collective consciousness of marine geoscientists, largely due to the efforts of Bruce C. Heezen (e.g., Ewing and Heezen, 1956), and later H.W. Menard (1958). Not until the late 1950’s did the globe-girdling ridge evolve into a major oceanographic issue. Its image, however, remained rather two-dimensional, based as it was upon widely spaced ocean traverses; a broad, rather gentle rise, usually cleft longitudinally and deeply along its crest.
KeywordsOceanic Crust Magma Chamber Rift Valley Spreading Center Seafloor Spreading
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