What Theory Did Alfred Wegener Propose

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What theory did Alfred Wegener propose? The theory of "continental drift" Explain the "continental drift" theory -the edges of the continents make a rough fit -the Appalachian mountain range breaks off in Newfoundland and reappears across the Atlantic ocean in Ireland, Scotland, and Scandinavia -the similarity of European and American fossils up to 180 million years ago and the dissimilarity of more recent fossils What was Wegener's explanation for the 2 predominant elevations of the Earth's surface? Wegener hypothesized that the difference in heights was due to continents being made up of less dense rock that the rocks of the oceanic basins. What did Wegener's hypothesis about the different elevations mean for his theory? It enabled the idea that the lighter and thicker continental blocks to float over the oceanic crust like icebergs What are the arguments against Wegener's theory? Geophysicists concluded that the Earth was made up of solid and stronger material that could not simply "float" over the seafloor. Why did the geophysicists believe the Earth's interior was so strong? They believed this because of the measurement of time. What discovery on the ocean floor resurrected Wegener's theory? The discovery that earthquakes in the oceanic floor coincided with submarine mid-oceanic ridges that ran for thousands of miles along the ocean floor. What proposal did Arthur Holmes make in 1928? He proposed that the seafloor may be spreading apart. What did Harry Hess propose in 1963? He proposed that molten rock erupts from the Earth's interior along mid-oceanic ridges, creating new seafloor. What magnetic field, polarity evidence supports the theory of plate tectonics? -the earth's magnetic field was especially strong over the oceanic ridges that were made up of iron rich materials -the magnetic field formed a zebra-striped
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