SeaFloor Spreading....How does the mirror images on The patterns on either side of a mid-ocean ridge provide..

....evidence for seafloor spreading ?SeaFloor Spreading....How does the mirror images on The patterns on either side of a mid-ocean ridge provide..
Hmmm! Oceanographic exploration in the 1950s led to a much better understanding of the ocean floor. Among the new findings was the discovery of zebra stripe-like magnetic patterns for the rocks of the ocean floor. These patterns were unlike any seen for continental rocks.





The U.S. Naval Oceanographic Office prepared a report summarizing available information on the magnetic stripes mapped for the volcanic rocks making up the ocean floor. After digesting the data in this report two British geologists, Frederick Vine and Drummond Matthews, and also Lawrence Morley of the Canadian Geological Survey, hypothesized that the magnetic striping was produced by repeated reversals of the Earth's magnetic field, not as earlier thought, by changes in intensity of the magnetic field.





Allan Cox and Richard Doell, and isotope geochemist Brent Dalrymple -- reconstructed the history of magnetic reversals for the past 4 million years. Assuming that the ocean floor moved away from the spreading center at a rate of several centimeters per year, they found there was a remarkable correlation between the ages of the Earth's magnetic reversals and the striping pattern.





Conclusion: In 1961, scientists began to theorize that mid-ocean ridges mark structurally weak zones where the ocean floor was being ripped in two lengthwise along the ridge crest. New magma from deep within the Earth rises easily through these weak zones and eventually erupts along the crest of the ridges to create new oceanic crust. This process, later called seafloor spreading, operating over many millions of years has built the 50,000 km-long system of mid-ocean ridges. This hypothesis was supported by several lines of evidence: (1) at or near the crest of the ridge, the rocks are very young, and they become progressively older away from the ridge crest; (2) the youngest rocks at the ridge crest always have present-day (normal) polarity; and (3) stripes of rock parallel to the ridge crest alternated in magnetic polarity (normal-reversed-normal, etc.), suggesting that the Earth's magnetic field has flip-flopped many times. By explaining both the zebralike magnetic striping and the construction of the mid-ocean ridge system, the seafloor spreading hypothesis quickly gained converts and represented another major advance in the development of the plate-tectonics theory. Furthermore, the oceanic crust now came to be appreciated as a natural ';tape recording'; of the history of the reversals in the Earth's magnetic field.





Great diagrams at the first link!SeaFloor Spreading....How does the mirror images on The patterns on either side of a mid-ocean ridge provide..
i think it have some link with the sky %26amp; cloude but no more
it proves that both sides are moving apart at relatively the same rate.. if it was subducting the 2 sides would look different.