The graphic below shows the striking distribution of fossils Western Africa and South America, and another in Antartica, India andĬentral Africa). Them to be if there had been Continental Drift (e.g. Wegener also presented examples where fossils ofĮxactly the same prehistoric species were distributed where you would expect With tropical climates, would be found near the North Pole and why the plains of Africa Wegener questioned why coal deposits, commonly associated His case he drew from the fields of geology, geography,īiology and paleontology. He knew that any argumentīased simply on the jigsaw fit of the continents could easily be explained away. To keep the discussion of Continental Drift alive until his death. Which has been learned in the past 70 years and start all over again."Ĭontinental Drift Theory:Building the Case "If we are to believe in Wegener's hypothesis we must forget everything Thomas Chamberlain, suggested just that : A radical view could even force experts to start Authorities are expert in the current view of Radical viewpoints threaten the authorities inĪ discipline. More importantly however, was that even the possibility ofĬontinental Drift was a huge threat to the authorities in What caused the extreme reaction? His work crossed disciplines.ĭisciplines attacked him as an amateur that did not fully grasp their Alfred Wegener did not even presentĬontinental Drift as a proven theory. The world had to wait until the 1960's for a wideĭiscussion of the Continental Drift Theory to be restarted.Ĭoncept openly discussed. The students' minds would not be befogged. The geologist Barry Willis summed it up best:įurther discussion of it merely incumbers the literature and befogs the Reactions eventually shut down serious discussion of the concept. It also drew the wrath of scientists from these disciplines. Wegener's theory drew from geology, geophysics, zoogeography and Used this and several other arguments to build his case. The map of soil types below (derived from The continents seem to have a jigsaw fit. You can see why Wegener suspected that the continents had once been joined. Only early scientists like Galileo needed to fear the reaction to We are taught that modern scientists areĭriven only by reason and facts. Theory tells us much about the workings of science. In 1912, Alfred Wegener proposed a theory that the continents had once been joined, and over time In particular, it explains the Gondwanan distribution of fossils.Alfred Wegener's Continental Drift Theory This concept explains why Earth does not expand through sea-floor spreading, why there is so little sediment accumulation on the ocean floor, and why oceanic rocks are much younger than continental rocks.įor a more detailed explanation, go to the Mountain Building section.Ĭontinental drift theory helps biogeographers to explain the disjunct biogeographic distribution of present-day life found on different continents but having similar ancestors. In effect, ocean basins are perpetually being "recycled," with the creation of new crust and the destruction of old oceanic lithosphere occurring simultaneously. As old oceanic crust is consumed at the trenches, new magma rises and erupts along the spreading ridges to form new crust. Many millions of years later, oceanic crust eventually descends at oceanic trenches in the mantle. Plate tectonics maintains that new oceanic crust continuously spreads away from mid-oceanic ridges in a conveyor-belt-like motion. Fragments drifted to where they are now located ( However, it was only during the 1960s, that the plate-tectonics theory was developed which allowed to explain the observations for large-scale motions of the Earth's lithospheric plates. In 1912, Alfred Wegener proposed that several continents had previously been one large continent, Pangaea which had broken apart.
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